KR20230136124A - Films containing bright silver-based quaternary nanostructures - Google Patents

Abstract

A film comprising Ag, In, Ga, and S (AIGS) nanostructures and at least one ligand bound to the nanostructures is disclosed. In some embodiments, AIGS nanostructures have a photon conversion efficiency greater than 32% and a peak wavelength emission of 480-545 nm. In some embodiments, the nanostructures have an emission spectrum with a FWHM of 24-38 nm.

Description

Films containing bright silver-based quaternary nanostructures

The present invention relates to the field of nanotechnology. More specifically, the present invention provides a thin, heavy metal-free photon conversion efficiency (PCE) of greater than 32% at a peak emission wavelength of 480-545 nm when excited using a blue light source with a wavelength of about 450 nm. Provides a nanostructured color conversion film.

Efficient conversion of color is important in lighting and display applications. In display applications, blue light sources with a wavelength of around 450 nm are most commonly used as backlights. Most applications require materials free of heavy metals such as Cd and Pb.

Increasing efficiency not only reduces wasted power but also increases emissions. Color converting thin films are characterized by photon conversion efficiency (PCE), which is defined as the number of photons emitted divided by the number of source photons. Green heavy metal-free QD color conversion films used in displays perform poorly due to limited absorption in blue light, which is commonly excited. Blue absorption is often inherently limited by the material system used, resulting in the need for much thicker films to absorb sufficient 450 nm light.

Thin films formed by deposition of QD ink are generally cured by UV irradiation. In most cases, this is followed by heat treatment at 180°C for up to 1 hour in the presence of air. The photon conversion efficiency of these films is limited by a combination of poor absorption and poor light conversion due to instability through these processing steps.

It has high band edge emission (BE), narrow full width at half maximum (FWHM), high quantum yield (QY) and reduced red shift, and has high ( There remains a need in the industry for Ag/In/Ga/S (AIGS) nanostructures useful for fabricating films with photon conversion efficiency (PCE) (>32%).

BRIEF SUMMARY OF THE INVENTION

The present invention provides thin, heavy metal-free nanostructured color conversion with a high photon conversion efficiency (PCE) of greater than 32% at a peak emission wavelength of 480-545 nm when excited using a blue light source with a wavelength of about 450 nm. Provides film. It uses Ag/In/Ga/S (AIGS) nanostructures in an ink formulation containing one or more ligands, and all handling of the ink, followed by deposition, processing and measurement of the film, is performed under blue or ultraviolet light. This is achieved by being performed in an oxygen-free environment before exposure to light. In some embodiments, AIGS nanostructures have a FWHM of 28-38 nm. In some embodiments, AIGS nanostructures have a FWHM of less than 32 nm. This narrow FWHM is achieved by adding at least one polyamino-ligand to the AIGS nanostructures, preparing the film layer, and performing all handling of the nanostructure ink, deposition of the ink, processing and measurement of the film in an oxygen-free environment. .

Thin films formed by deposition of QD ink are typically cured by UV irradiation. In most cases, this is followed by heat treatment at 180°C for up to 1 hour in the presence of air. It has been found that photon conversion efficiency is reduced by poor absorption and poor light conversion due to instability through these processing steps.

Disclosed herein are films comprising AIGS nanostructures in an ink formulation comprising at least one ligand that achieve a PCE of >32% after heat treatment. In some embodiments, a film comprising AIGS nanostructures, at least one ligand, and exhibiting a PCE of greater than 32% at a peak emission wavelength of 480-545 nm when excited using a blue light source with a wavelength of 450 nm. provided. PCE is calculated by integrating the emission spectrum from 484nm to 700nm, with the green portion defined as 484-588nm. In some embodiments, the film is a thin (5-15 μm) color conversion film.

As manufactured, this film has good blue light absorption (>95%) near the absorption at about 450 nm, but has moderate emission properties. However, if processed in the absence of oxygen and/or light and/or encapsulated before exposing the films to UV or blue light, the release properties of these films are greatly improved.

In some embodiments, the film further comprises at least one monomer incorporated into the ligand that coats the AIGS surface. In some embodiments, at least one monomer is an acrylate. In some embodiments, the monomer is ethyl acrylate, hexamethylene diacrylate (HDDA), tetrahydrofurfuryl acrylate, tri(propylene glycol) diacrylate, 1,4-bis(acryloyloxy)butane, or iso At least one of bornyl acrylate.

As a method for manufacturing AIGS film,

(a) providing AIGS nanostructures and at least one ligand that coats the nanostructures;

(b) mixing the AIGS nanostructures of (a) with at least one organic resin; and

(c) preparing a first film comprising the mixed AIGS nanostructures, the at least one ligand coating the nanostructures, and at least one organic resin on a first barrier layer;

(d) curing the film by UV irradiation and/or baking;

(e) encapsulating the first film between the first and second barrier layers;

A method of making an AIGS film is provided, wherein the encapsulated film exhibits a conversion efficiency (PCE) of greater than 32% at a peak emission wavelength of 480-545 nm when excited using a blue light source with a wavelength of about 450 nm.

In some embodiments, the AIGS nanostructures further include at least one monomer incorporated into at least one ligand that coats the AIGS surface.

also

(f) addition of at least one oxygen-reactive material to the mixture of AIGS nanostructures and ligands in (a), addition of at least one oxygen-reactive material to the mixture of (b), and/or the above prepared in (c). forming a second film comprising at least one oxygen-reactive material on top of the first film; and/or

(g) forming a sacrificial barrier layer that temporarily blocks oxygen and/or water on the first film prepared in (c), and measuring the PCE of the film, then forming the sacrificial barrier layer removing

A method further including is provided.

also

(a) encapsulating the film prior to heat treatment and/or measurement;

(b) use of oxygen-reactive materials as part of the formulation during heat treatment or light exposure; and/or

(c) Temporary blocking of oxygen through the use of a sacrificial barrier layer

A method including is provided.

In some embodiments, the nanostructures have an emission spectrum with a FWHM of less than 40 nm. In some embodiments, the nanostructures have an emission spectrum with a FWHM of 24-38 nm. In some embodiments, the nanostructures have an emission spectrum with a FWHM of 27-32 nm. In some embodiments, the nanostructures have an emission spectrum with a FWHM of 29-31 nm.

In some embodiments, nanostructures have a QY of 80-99.9%. In some embodiments, nanostructures have a QY of 85-95%. In some embodiments, nanostructures have a QY of about 86-94%. In some embodiments, the nanostructures have an OD ₄₅₀ /mass (mL ^. mg ^−1. cm ⁻¹ ) greater than 0.8, where OD is the optical density. In some embodiments, the nanostructures have an OD ₄₅₀ /mass (mL ^. mg ^-1. cm ^-1 ) ranging from 0.8-2.5. In some embodiments, the nanostructures have an OD ₄₅₀ /mass (mL ^. mg ^-1. cm ^-1 ) ranging from 0.87-1.9. In some embodiments, the average diameter of the nanostructures is less than 10 nm by transmission electron microscopy (TEM). In some embodiments, the average diameter is about 5 nm.

In some embodiments, at least about 80% of the emission is band-edge emission. In some embodiments, at least about 90% of the emission is band-edge emission. In some embodiments, 92-98% of the emission is band-edge emission. In some embodiments, 93-96% of the emission is band-edge emission.

In some embodiments, AIGS nanostructures have a peak emission wavelength (PWL) of about 450 nm.

In some embodiments, the AIGS nanostructures include a gradient from increased gallium at the surface of the nanostructures to decreased gallium at the center of the nanostructures.

In some embodiments, the at least one ligand is an amino ligand, a polyamino ligand, a ligand comprising a mercapto group, or a ligand comprising a silane group. It was unexpectedly discovered that using polyamino ligands results in AIGS-containing films with FWHMs greater than 32 nm.

In some embodiments, the at least one polyamino-ligand is a polyamino alkane, polyamino-cycloalkane, polyamino heterocyclic compound, polyamino functionalized silicone, or polyamino substituted ethylene glycol. In some embodiments, the polyamino-ligand is a C _2-20 alkane or C _2-20 cycloalkane substituted with 2 or 3 amino groups and optionally containing 1 or 2 amino groups in place of a carbon group. In some embodiments, the polyamino-ligand is 1,3-cyclohexanebis(methylamine), 2,2-dimethyl-1,3-propanediamine, or tris(2-aminoethyl)amine.

In some embodiments, the ligand is a compound of Formula I:

During the ceremony:

x is 1 to 100;

y is 0 to 100;

R ² is C _1-20 alkyl.

In some embodiments, x = 19, y = 3, and R ² = -CH ₃ .

In some embodiments, the at least one ligand is (3-aminopropyl)trimethoxy-silane); (3-mercaptopropyl)triethoxysilane; DL-α-lipoic acid; 3,6-dioxa-1,8-octanedithiol; 6-mercapto-1-hexanol; Methoxypolyethylene glycol amine (about m.w. 500); poly(ethylene glycol) methyl ether thiol (about m.w. 800); diethyl phenylphosphonite; Dibenzyl N,N-diisopropylphosphoramidite; di-tert-butyl N,N-diisopropylphosphoramidite; tris(2-carboxyethyl)phosphine hydrochloride; poly(ethylene glycol) methyl ether thiol (ca. m.w. 2000); Methoxypolyethylene glycol amine (about m.w.750); acrylamide; Or polyethyleneimine. The m.w. of the polymer is determined by mass spectrometry.

In some embodiments, the at least one ligand is selected from amino-polyalkylene oxide (about m.w. 1000) and methoxypolyethylene glycol amine (about m.w. 500); Amino-polyalkylene oxide (about m.w. 1000) and 6-mercapto-1-hexanol; Amino-polyalkylene oxide (about m.w. 1000) and (3-mercaptopropyl)triethoxysilane; and a combination of 6-mercapto-1-hexanol and methoxypolyethylene glycol amine (about m.w. 500).

In some embodiments, the AIGS nanostructures further include at least one monomer incorporated into at least one ligand that coats the AIGS surface.

also

(a) AIGS nanostructures exhibiting a PCE greater than 32%, and

(b) at least one organic resin

A nanostructure composition comprising a is provided.

In some embodiments, the at least one organic resin is cured.

Methods for preparing nanostructure compositions described herein are provided, comprising:

(a) providing AIGS nanostructures and at least one ligand that coats the nanostructures;

(b) mixing the nanostructures of (a) with at least one organic resin;

(c) preparing a first film comprising the mixed AIGS nanostructures, the at least one ligand coating the nanostructures, and at least one organic resin on a first barrier layer;

(d) curing the film by UV irradiation and/or baking; and

(e) encapsulating the first film between the first and second barrier layers,

The encapsulated film exhibits a conversion efficiency (PCE) of greater than 32% at a peak emission wavelength of 480-545 nm when excited using a blue light source with a wavelength of about 450 nm.

In some embodiments, the nanostructures of (a) further comprise at least one monomer incorporated into a ligand that coats the AIGS surface. In some embodiments, at least one monomer is an acrylate. In some embodiments, the monomer is at least one of ethyl acrylate, HDDA, tetrahydrofurfuryl acrylate, tri(propylene glycol) diacrylate, 1,4-bis(acryloyloxy)butane, or isobornyl acrylate. .

In some embodiments, the method is performed before the encapsulated film is exposed to air with measurement of the emission spectrum of the AIGS nanostructures. In some embodiments, the method is performed under an inert atmosphere.

In some embodiments, the method

(f) addition of at least one oxygen-reactive material to the mixture of AIGS nanostructures and ligand of (a),

(g) addition of at least one oxygen-reactive material to the mixture of (b), and/or

(h) forming a second film comprising at least one oxygen-reactive material on top of the first film prepared in (c); and/or

(i) forming a sacrificial barrier layer that temporarily blocks oxygen and/or water on the first film prepared in (c), and measuring the PCE of the film, then removing the sacrificial barrier layer. thing

It further includes.

In some embodiments, the two barrier layers exclude oxygen and/or water.

In some embodiments, 92-98% of the emission is band-edge emission. In some embodiments, 93-96% of the emission is band-edge emission.

also

(a) providing AIGS nanostructures and at least one ligand that coats the nanostructure surface; and

(b) mixing the composition obtained in (a) with at least one second ligand.

A method of preparing a composition comprising a is provided.

In some embodiments, the composition in (a) further comprises an organic resin. In some embodiments, the composition in (a) further comprises at least one monomer incorporated into a ligand that coats the AIGS surface. In some embodiments, the method further includes inkjet printing the composition.

In some embodiments, the method further comprises preparing a film comprising the composition obtained in (b). In some embodiments, the method further includes curing the film. In some embodiments, the film is cured by heating. In some embodiments, the film is cured by exposure to electromagnetic radiation.

Also provided is a device comprising the film described above.

Additionally, as a nanostructure molded article,

(a) first conductive layer;

(b) a second conductive layer; and

(c) a film comprising an AIGS nanostructured layer between the first conductive layer and the second conductive layer.

Including,

A nanostructured molded article is provided wherein the nanostructured layer includes AIGS nanostructures having a PCE of greater than 32%.

also

back plane;

a display panel disposed on the backplane; and

A film comprising an AIGS nanostructured layer comprising AIGS nanostructures having a PCE greater than 32%, wherein the nanostructured layer is disposed on a display panel.

A nanostructured color converter comprising a is provided.

In some embodiments, the nanostructured layer includes a patterned nanostructured layer. In some embodiments, the backplane includes an LED, LCD, OLED, or microLED.

The structure and operation of various embodiments of the invention, as well as additional features and advantages of the invention, are described in detail below with reference to the accompanying drawings. Note that the invention is not limited to the specific embodiments described herein. Such embodiments are presented herein for illustrative purposes only. Additional embodiments will be apparent to those skilled in the art based on the teachings contained herein.

The accompanying drawings, which are incorporated in and form a part of this specification, illustrate the present embodiments and, together with the detailed description, further explain the principles of the present embodiments and enable those skilled in the art to make and use the present embodiments. It plays a role in making it usable.
Figure 1 is a photograph, from left to right, of first and third films that did not contain polyamino ligands and showed extension wrinkling. The second and fourth films containing polyamino ligand showed no wrinkles.
Figures 2a-2c and TEM images show AIGS nanostructures before ion exchange treatment (Figure 2a), after one ion exchange treatment (Figure 2b), and after two ion exchange treatments (Figure 2c).
Figures 3a and 3b are schematic diagrams for unencapsulated (Figure 3a) and encapsulated (Figure 3b) films.
Figure 4 is a scatter graph showing QY% exhibited by mixtures of various ligands.
Figure 5 is a scatter graph showing ligand combinations that provide improved QY% (good combinations) and combinations that provide reduced QY% (poor combinations).
Figure 6 is a graph showing the QY% of various ligand combinations before (NG), after ligand exchange (LE), and after thermal testing for 30 minutes.
Figure 7 is a graph showing the QY% of various ligand combinations at various ligand ratios.
Figure 8 is two scatter graphs showing the PCE of AIGS film with normal post bake (PoB) measurement (left graph) and encapsulation before PCE measurement (right graph).
Figure 9 is two scatter graphs showing the PCE of AIGS films without (left graph) and with (right graph) encapsulation before PCE measurement, baked at 180 °C.
Figure 10 is a bar graph showing the photoluminescence quantum yield (PLQY) of ligand exchanged AIGS nanostructures in various solvents at room temperature and 80°C.
Figure 11 is a bar graph showing the QY of ligand exchanged AIGS nanostructures in the presence of various monomers.
Figure 12 is a line graph showing the film external quantum efficiency (EQE) of AIGS nanostructures that were ligand exchanged after UV curing and treated with various monomers.
Figure 13 is a bar graph showing blue light absorption of AIGS nanostructure ink that was ligand exchanged, treated with various monomers, and spun coated at 800 rpm.
Figure 14 is a line graph showing the effect of diamine ((1,3-bis(aminomethyl)cyclohexane) on film EQE after UV and post bake (POB) at 180° C. for 30 minutes.
Figure 15 is a line graph showing the effect of added diamine on viscosity measured indirectly as blue light absorption in the film after spin coating at 800 RPM.
Figure 16 is a bar graph showing the effect of diamine (DA) and ligand exchange (LE) on solution QY. The graph shows that the QY drop after heating at 180 ^o C becomes smaller with increasing amount of diamine.
Figure 17 is a line graph showing the effect of increasing DA amount on film PCE after UV curing.
Figure 18 is a line graph showing the effect on film blue light absorbance by increasing the amount of DA in the film.
Figure 19 is a line graph showing the effect of DA added in monomer dispersion, in LE, and in both monomer dispersion and LE on PCE film blue light absorbance.
Figure 20 is a line graph showing the effect of DA added in monomer dispersion, in LE, and in both monomer dispersion and LE on PCE film blue light absorbance and film viscosity.
Figure 21 is a line graph showing the effect of various additives on initial film EQE.
Figure 22 is a line graph showing the effect of various additives on film EQE after POB.
Figure 23 is a line graph showing the effect of additional additives on film EQE and blue light absorption.
The features and advantages of the invention will become more apparent from the detailed description set forth below when taken in conjunction with the drawings, in which like reference characters identify corresponding elements throughout. In the drawings, like reference numbers generally indicate identical, functionally similar, and/or structurally similar elements. The drawing in which an element first appears is indicated by the leftmost digit(s) in the corresponding reference number. Unless otherwise indicated, the drawings provided throughout this disclosure should not be construed as to-scale drawings.

definitions

Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by a person of ordinary skill in the art to which the invention pertains. The following definitions supplement definitions in the art, relate to this application, and are not attributable to any related or unrelated instances, e.g., any commonly owned patents or applications. Although any methods and materials similar or equivalent to those described herein can be used in the practice of testing the present invention, the preferred materials and methods are described herein. Accordingly, the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting.

As used in this specification and the appended claims, the singular forms “a”, “an” and “the” include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to a “nanostructure” includes a plurality of such nanostructures, etc.

As used herein, the term “about” indicates that the value of a given quantity varies by +/-10% of that value. For example, “about 100 nm” encompasses a range of sizes including from 90 nm to 110 nm.

A “nanostructure” is a structure that has at least one area or characteristic dimension that has a dimension of less than about 500 nm. In some embodiments, the nanostructure has a dimension of less than about 200 nm, less than about 100 nm, less than about 50 nm, less than about 20 nm, or less than about 10 nm. Typically, the area or characteristic dimension will be along the minimum axis of the structure. Examples of such structures include nanowires, nanorods, nanotubes, branched nanostructures, nanotetrapods, tripods, bipods, nanocrystals, nanodots, quantum dots, nanoparticles. Includes etc. Nanostructures can be, for example, substantially crystalline, substantially monocrystalline, polycrystalline, amorphous, or combinations thereof. In some embodiments, each of the three dimensions of the nanostructure has a dimension of less than about 500 nm, less than about 200 nm, less than about 100 nm, less than about 50 nm, less than about 20 nm, or less than about 10 nm. .

The term “heterostructure” when used with reference to nanostructures refers to nanostructures characterized by at least two different and/or distinguishable material types. Typically, one region of the nanostructure includes a first material type, while a second region of the nanostructure includes a second material type. In certain embodiments, the nanostructure includes a core of a first material and at least one shell of a second (or third, etc.) material, where different material types are formed along, for example, the long axis of the nanowire, It is distributed radially about the long axis of the arm of the branched nanowire or the center of the nanocrystal. The shell may, but need not, completely cover the nanostructure to be considered a heterostructure or adjacent materials to be considered a shell; For example, a nanocrystal featuring a core of one material covered by small islands of a second material is a heterostructure. In other embodiments, different material types are placed at different locations within the nanostructure; For example, it is distributed along the main axis (long axis) of the nanowire or along the long axis of the arms of a branched nanowire. Different regions within the heterostructure may include entirely different materials, or different regions may include different dopants, or a base material (eg, silicon) with different concentrations of the same dopant.

As used herein, “diameter” of a nanostructure refers to the diameter of the cross-section perpendicular to the first axis of the nanostructure, where the first axis is the largest in length with respect to the second and third axes. There is a difference (the second and third axes are the two axes whose lengths are most nearly equal to each other). The first axis does not necessarily have to be the longest axis of the nanostructure; For example, for a disk-shaped nanostructure, the cross-section would be a substantially circular cross-section perpendicular to the short longitudinal axis of the disk. If the cross section is not circular, the diameter is the average of the major and minor axes of the cross section. For elongated or high aspect ratio nanostructures, such as nanowires, the diameter is measured across a cross-section perpendicular to the longest axis of the nanowire. For spherical nanostructures, the diameter is measured from one side to the other through the center of the sphere.

The terms “crystalline” or “substantially crystalline,” when used in reference to nanostructures, refer to the fact that nanostructures typically exhibit long-range ordering over one or more dimensions of the structure. refers to It will be understood by those skilled in the art that the term "long-range regularity" will depend on the absolute size of the specific nanostructures, since the regularity for a single crystal cannot extend beyond the boundaries of the crystal. In this case, “long-range regularity” will mean substantial regularity over at least most of the dimensions of the nanostructure. In some cases, the nanostructure may have an oxide or other coating, or may be composed of a core and at least one shell. It will be appreciated that in such cases, the oxide, shell(s), or other coating may, but need not, exhibit such regularity (eg, it may be amorphous, polycrystalline, or otherwise). In such instances, the phrases “crystalline,” “substantially crystalline,” “substantially single crystalline,” or “single crystalline” refer to the central core of the nanostructure (excluding coating layers or shells). As used herein The terms “crystalline” or “substantially crystalline,” as used, also mean that the structure exhibits substantial long-range regularity (e.g., regularity over at least about 80% of the length of at least one axis of the nanostructure or its core). In so far as it is indicated, it is intended to encompass structures containing various defects, stacking faults, atomic substitutions, etc. Additionally, between the core and the exterior of the nanostructure, or the core and the adjacent shell. It will be appreciated that the interface between, or between a shell and a second adjacent shell, may comprise non-crystalline regions, or may even be amorphous, whether the nanostructure is crystalline or substantially crystalline as defined herein. can't stop it from happening.

When used in reference to a nanostructure, the term “single crystalline” indicates that the nanostructure is substantially crystalline and comprises substantially a single crystal. When used in reference to a nanostructured heterostructure comprising a core and one or more shells, “single crystalline” indicates that the core is substantially crystalline and comprises substantially a single crystal.

A “nanocrystal” is a nanostructure that is substantially single crystalline. Accordingly, a nanocrystal has at least one region or characteristic dimension having a dimension of less than about 500 nm. In some embodiments, the nanocrystals have dimensions of less than about 200 nm, less than about 100 nm, less than about 50 nm, less than about 20 nm, or less than about 10 nm. The term “nanocrystal” encompasses substantially single crystalline nanostructures that contain various defects, stacking faults, atomic substitutions, etc., and substantially single crystalline nanostructures that do not have such defects, defects, or substitutions. It is intended to. In the case of nanocrystal heterostructures comprising a core and one or more shells, the core of the nanocrystal is typically substantially monocrystalline, but the shell(s) need not be. In some embodiments, each of the three dimensions of the nanocrystal has a dimension of less than about 500 nm, less than about 200 nm, less than about 100 nm, less than about 50 nm, less than about 20 nm, or less than about 10 nm. .

The term “quantum dot” (or “dot”) refers to nanocrystals that exhibit quantum confinement or exciton confinement. Quantum dots may be substantially homogeneous in material properties or, in certain embodiments, heterogeneous, including, for example, a core and at least one shell. The optical properties of quantum dots can be influenced by their particle size, chemical composition, and/or surface composition, and can be determined by suitable optical testing available in the art. The ability to tailor nanocrystal sizes, for example, to a range between about 1 nm and about 15 nm makes it possible for light emission coverage over the entire optical spectrum to provide great versatility in color rendering.

The term “oxygen-free ligand” as used herein refers to coordinating molecules that do not contain oxygen atoms that can coordinate or react with metal ions.

A “ligand” is a molecule that can interact (weakly or strongly) with one or more sides of a nanostructure, such as through covalent, ionic, van der Waals, or other molecular interactions with the surface of the nanostructure.

“Photoluminescence quantum yield” (QY) is the ratio of photons emitted to photons absorbed, eg, by a nanostructure or group of nanostructures. As known in the art, quantum yield is typically measured as the absolute change in photon count upon illumination of a sample inside an integrating sphere, or using well-characterized standard samples with known quantum yield values. It is determined by comparative method.

“Peak emission wavelength” (PWL) is the wavelength at which the radiometric emission spectrum of a light source reaches its maximum.

As used herein, the term “full width at half maximum” (FWHM) is a measure of the size distribution of nanostructures. Emission spectra of nanostructures generally have the shape of a Gaussian curve. The width of the Gaussian curve is defined as FWHM and gives an idea about the size distribution of particles. Smaller FWHM corresponds to a narrower nanostructure nanocrystal size distribution. FWHM also depends on the emission wavelength maximum.

Band-edge emission is centered at higher energy (lower wavelength) with a smaller offset from the absorption onset energy compared to the corresponding defect emission. Additionally, band-edge emission has a narrower wavelength distribution compared to defect emission. Both band-edge and defect emissions follow a normal (approximately Gaussian) wavelength distribution.

Optical density (OD) is a commonly used method to quantify the concentration of solutes or nanoparticles. According to Beer-Lambert's law, the absorbance (also known as "extinction") of a particular sample is proportional to the concentration of solutes that absorb light of a particular wavelength.

Optical density is the optical attenuation per centimeter of material as measured using a standard spectrometer, typically specified for 1 cm path length. Nanostructure solutions are often measured by their optical density instead of mass or molar concentration because it is directly proportional to concentration and is a more convenient way to express the amount of optical absorption occurring in the nanostructure solution at the wavelength of interest. A nanostructure solution with an OD of 100 is 100 times more concentrated (100 times more particles per mL) than a product with an OD of 1.

Optical density can be measured at any wavelength of interest, such as the wavelength chosen to excite the fluorescent nanostructure. Optical density is a measure of the intensity lost when light passes through a nanostructure solution at a specific wavelength and is calculated using the formula:

OD = log ₁₀ *(I _OUT /I _IN )

During the meal

I _OUT = intensity of radiation entering the cell; and

I _IN = intensity of radiation penetrating the cell.

The optical density of nanostructure solutions can be measured using a UV-VIS spectrometer. Therefore, through the use of a UV-VIS spectrometer, it is possible to determine the amount of nanostructures present in a sample by calculating the optical density.

Unless explicitly stated otherwise, ranges recited herein are inclusive.

Various additional terms are defined or otherwise characterized herein.

AIGS nanostructures

Nanostructures comprising Ag, In, Ga and S are provided, where the nanostructures have a peak emission wavelength (PWL) between 480-545 nm. In some embodiments, at least about 80% of the emission is band-edge emission. The percentage of band-edge emission is calculated by fitting the Gaussian peaks (usually greater than 2) of the nanostructure emission spectrum and dividing the area of the peak whose energy is closer to the nanostructure bandgap (indicating band-edge emission) of all peak areas. It is calculated by comparing with the sum (band-edge + defect emission).

In one embodiment, the nanostructures have a FWHM emission spectrum of less than 40 nm. In another embodiment, the nanostructures have a FWHM of 36-38 nm. In some embodiments, the nanostructure has an emission spectrum with a FWHM of 27-32 nm. In some embodiments, the nanostructure has an emission spectrum with a FWHM of 29-31 nm.

In other embodiments, the nanostructures have a QY of about 80% to 99.9%. In other embodiments, the nanostructures have a QY of 85-95%. In other embodiments, the nanostructures have a QY of about 86% to about 94%. In some embodiments, at least 80% of the emission is band-edge emission. In other embodiments, at least 90% of the emission is band-edge emission. In other embodiments, at least 95% of the emission is band-edge emission. In some embodiments, 92-98% of the emission is band-edge emission. In some embodiments, 93-96% of the emission is band-edge emission.

AIGS nanostructures provide high blue light absorption. As a predicted value for blue light absorption efficiency, the optical density at 450 nm (OD ₄₅₀ /mass) on a mass basis is calculated by measuring the optical density of the nanostructure solution in a 1 cm path length cuvette and all volatiles under vacuum (<200 mTorr). It is calculated by removing and dividing by dry mass per mL (mg/mL) of the same solution. In one embodiment, the nanostructures provided herein have an OD ₄₅₀ /mass (mL ^. mg ^-1. cm ^-1 ) of at least 0.8. In another embodiment, the nanostructures have an OD ₄₅₀ /mass (mL ^. mg ^-1. cm ^-1 ) of 0.8-2.5. In another embodiment, the nanostructures have an OD ₄₅₀ /mass (mL ^. mg ^-1. cm ^-1 ) of 0.87-1.9.

In one embodiment, the nanostructures were treated with gallium ions such that ion exchange of gallium for indium occurs throughout the AIGS nanostructure. In another embodiment, the nanostructures have Ag, In, Ga, and S in the core and are processed by ion exchange with gallium ions and S. In another embodiment, the nanostructures have Ag, In, Ga, and S in the core and are processed by ion exchange with silver ions, gallium ions, and S. In some embodiments, the ion exchange treatment results in a gradient of gallium, silver, and/or sulfur throughout the nanostructures.

In one embodiments, the average diameter of the nanostructures is less than 10 nm as measured by TEM. In another embodiment, the average diameter is about 5 nm.

AIGS nanostructures prepared using GaX ₃ (X = F, Cl, or Br) precursor and oxygen-free ligand

Reports of AIGS preparations in the literature have not attempted to exclude oxygen-containing ligands. In the coating of AIGS with gallium, oxygen-containing ligands are often used to stabilize the Ga precursor. Gallium(III) acetylacetonate is generally used as an easily air-handled precursor, whereas Ga(III) chloride requires careful handling due to its moisture sensitivity. For example, Kameyama et al., ACS Appl. Mater. Interfaces 10:42844-42855 (2018), gallium (III) acetylacetonate was used as a precursor for core and core/shell structures. Because gallium has a high affinity for oxygen, the use of oxygen-containing ligands and gallium precursors that were not prepared under oxygen-free conditions, when Ga and S precursors are used to generate nanostructures containing significant gallium content, causes gallium oxide and Likewise, unwanted side reactants may be generated. These side reactants may cause defects in nanostructures and result in lower quantum yields.

In some embodiments, AIGS nanostructures are prepared using oxygen-free GaX ₃ (X = F, Cl, or Br) as a precursor in the preparation of AIGS cores. In some embodiments, AIGS nanostructures are prepared using GaX ₃ (X = F, Cl, or Br) as an oxygen-free ligand and precursor in the preparation of Ga-enriched AIGS nanostructures. In some embodiments, AIGS nanostructures are prepared using GaX ₃ (X = F, Cl, or Br) as an oxygen-free ligand and precursor in the preparation of the AIGS core. In some embodiments, AIGS nanostructures are prepared using GaX ₃ (X = F, Cl, or Br) as an oxygen-free ligand and precursor in the ion exchange processing of AIGS cores and in the preparation of AIGS cores.

Nanostructures comprising Ag, In, Ga and S are provided, wherein the nanostructures have a peak emission wavelength (PWL) between 480-545 nm and the nanostructures have GaX ₃ (X = F, Cl, or Br ) were prepared using precursors and oxygen-free ligands.

In some embodiments, nanostructures prepared using a GaX ₃ (X = F, Cl, or Br) precursor and oxygen-free ligand display a FWHM emission spectrum of 35 nm or less. In some embodiments, nanostructures prepared using GaX ₃ (X = F, Cl, or Br) precursor and oxygen-free ligand display a FWHM of 30-38 nm. In some embodiments, nanostructures prepared using a GaX ₃ (X = F, Cl, or Br) precursor and oxygen-free ligand have a QY of at least 75%. In some embodiments, nanostructures prepared using a GaX ₃ (X = F, Cl, or Br) precursor and oxygen-free ligand have a QY of 75-90%. In some embodiments, nanostructures prepared using a GaX ₃ (X = F, Cl, or Br) precursor and an oxygen-free ligand have a QY of about 80%.

The AIGS nanostructures prepared herein provide high blue light absorption. In some embodiments, the nanostructures have an OD ₄₅₀ /mass (mL·mg ^-1 ·cm ^-1 ) of at least 0.8. In some embodiments, the nanostructures have an OD ₄₅₀ /mass (mL ^. mg ^-1. cm ^-1 ) of 0.8-2.5. In another embodiment, the nanostructures have an OD ₄₅₀ /mass (mL ^. mg ^-1. cm ^-1 ) of 0.87-1.9.

In some embodiments, the nanostructures are treated with gallium ions such that ion exchange of gallium for indium occurs throughout the AIGS nanostructure. In some embodiments, the nanostructures include Ag, In, Ga, and S in a core with a gradient of gallium between the surface and the center of the nanostructure. In some embodiments, the nanostructures are AIGS cores treated with AGS and fabricated using a GaX ₃ (X = F, Cl, or Br) precursor and an oxygen-free ligand in the core. In some embodiments, the nanostructures are AIGS nanostructures and are prepared using a GaX ₃ (X = F, Cl, or Br) precursor and an oxygen-free ligand. In some embodiments, AIGS nanostructures are formed by reacting a preformed In-Ga reagent with Ag ₂ S nanostructures to provide AIGS nanostructures, which are then ion exchanged with gallium by reacting with an oxygen-free Ga salt to form AIGS nanostructures. It is manufactured by doing.

Methods for manufacturing AIGS nanostructures

(a) preparing a mixture comprising AIGS cores, sulfur source, and ligand;

(b) Adding the mixture obtained in (a) to a mixture of gallium carboxylate and ligand, at a temperature of 180-300 °C, to provide ion exchanged nanostructures with a gradient of gallium from the surface to the center of the nanostructures. steps; and

(c) isolating the nanostructures

Methods for manufacturing AIGS nanostructures are provided, including.

In some embodiments, the nanostructures have a PWL of 480-545 nm, where at least about 60% of the emission is band-edge emission.

also

(a) reacting Ga(acetylacetonate) ₃ , InCl ₃ , and a ligand, optionally in a solvent, at a temperature sufficient to provide an In-Ga reagent, and

(b) reacting the In-Ga reagent and Ag ₂ S nanostructures at a temperature sufficient to produce AIGS nanostructures,

(c) reacting the AIGS nanostructures with an oxygen-free Ga salt in a solvent containing the ligand at a temperature sufficient to provide ion-exchanged nanostructures with a gradient of gallium from the surface to the center of the nanostructures.

Methods for manufacturing AIGS nanostructures containing are provided.

In some embodiments, the nanostructures have a PWL of 480-545 nm, where at least about 60% of the emission is band-edge emission.

In some embodiments, the ligand is an alkylamine. In some embodiments, the alkylamine ligand is oleylamine. In some embodiments, the ligand is used in excess and acts as a solvent and the stated solvent is absent from the reaction. In some embodiments, a solvent is present in the reaction. In some embodiments, the solvent is a high boiling point solvent. In some embodiments, the solvent is octadecene, squalane, dibenzyl ether, or xylene. In some embodiments, the sufficient temperature in (a) is 100 to 280° C.; The temperature sufficient for (b) is 150 to 260° C.; And in (c), the sufficient temperature is 170 to 280°C. In some embodiments, the sufficient temperature in (a) is about 210° C.; The sufficient temperature in (b) is about 210° C.; And in (c), the sufficient temperature is about 240°C.

In some embodiments, at least 80% of the emission is band-edge emission. In other embodiments, at least 90% of the emission is band-edge emission. In other embodiments, at least 95% of the emission is band-edge emission. In some embodiments, 92-98% of the emission is band-edge emission. In some embodiments, 93-96% of the emission is band-edge emission.

Examples of ligands are in U.S. Pat. It is disclosed in In some embodiments, the ligand is an alkylamine. In some embodiments, the ligand is an alkylamine selected from the group consisting of dodecylamine, oleylamine, hexadecylamine, dioctylamine, and octadecylamine.

In some embodiments, the sulfur source in (a) is trioctylphosphine sulfide, elemental sulfur, octanethiol, dodecanethiol, octadecanethiol, tributylphosphine sulfide, cyclohexyl isothiocyanate, α-toluene. thiol, ethylene trithiocarbonate, allyl mercaptan, bis(trimethylsilyl) sulfide, trioctylphosphine sulfide, or combinations thereof. In some embodiments, the sulfur source in (a) is derived from S ₈ .

In one embodiment, the sulfur source is derived from S ₈ .

In one embodiment, the temperature in (a) and (b) is about 270°C.

In some embodiments, the mixture in (b) further comprises a solvent. In some embodiments, the solvent is trioctylphosphine, dibenzyl ether, or squalane.

In some embodiments, the gallium carboxylate is gallium C _2-24 carboxylate. Examples of C _2-24 carboxylates are acetate, propionate, butanoate, pentanoate, hexanoate, heptanoate, octanoate, nonanoate, decanoate, undecanoate, tride. Includes decanoate, tetradecanoate, pentadecanoate, hexadecanoate, octadecanoate (oleate), nonadecanoate and icosanoate. In one embodiment, the gallium carboxylate is gallium oleate.

In some embodiments, the ratio of gallium carboxylate for AIGS cores is 0.008-0.2 mmol gallium carboxylate per mg AIGS. In one embodiment, the ratio of gallium carboxylate for AIGS cores is 0.04 mmol gallium carboxylate per mg AIGS.

In a further embodiment, AIGS nanostructures are isolated, for example by precipitation. In some embodiments, AIGS nanostructures are precipitated by addition of a non-solvent to the AIGS nanostructures. In some embodiments, the non-solvent is a toluene/ethanol mixture. Precipitated nanostructures may be further isolated by centrifugation and washing with a non-solvent for nanostructures.

(a) preparing a mixture comprising gallium halide and AIGS cores in a solvent and maintaining the mixture for a time sufficient to provide ion-exchanged nanostructures with a gradient of gallium from the surface to the center of the nanostructures. step; and

(b) isolating nanostructures

A method of manufacturing nanostructures is also provided, including.

In some embodiments, the nanostructures have a PWL of 480-545 nm, where at least about 60% of the emission is band-edge emission.

In some embodiments, at least 80% of the emission is band-edge emission. In other embodiments, at least 90% of the emission is band-edge emission. In other embodiments, at least 95% of the emission is band-edge emission.

In some embodiments, the gallium halide is gallium chloride, bromide, or iodide. In one embodiment, the gallium halide is gallium iodide.

In some embodiments, the solvent includes trioctylphosphine. In some embodiments, the solvent includes toluene.

In some embodiments, the sufficient time in (a) is 0.1-200 hours. In some embodiments, the sufficient time in (a) is about 20 hours.

In some embodiments, the mixture is maintained between 20 and 100 °C. In one embodiment, the mixture is maintained at about room temperature (20° C. to 25° C.).

In some embodiments, the molar ratio of gallium halide to AIGS cores ranges from about 0.1 to about 30.

In a further embodiment, AIGS nanostructures are isolated, for example by precipitation. In some embodiments, AIGS nanostructures are precipitated by addition of a non-solvent to the AIGS nanostructures. In some embodiments, the non-solvent is a toluene/ethanol mixture. Precipitated nanostructures may be further isolated by centrifugation and/or washing with a non-solvent for nanostructures.

(a) preparing a mixture comprising AIGS nanostructures, a sulfur source, and a ligand;

(b) the mixture obtained in (a) was mixed with GaX ₃ (X = F, Cl, or Adding to the mixture of Br) and oxygen-free ligand; and

(d) isolating nanostructures

Methods for manufacturing nanostructures, including, are also provided.

In some embodiments, the nanostructures have a PWL of 480-545 nm.

In some embodiments, the preparation in (a) occurs under anaerobic conditions. In some embodiments, preparation in (a) takes place in the glovebox.

In some embodiments, the addition in (b) occurs under anoxic conditions. In some embodiments, the addition in (b) takes place in the glovebox.

In some embodiments, at least 80% of the emission is band-edge emission. In other embodiments, at least 90% of the emission is band-edge emission. In other embodiments, at least 95% of the emission is band-edge emission.

Examples of ligands are in U.S. Pat. It is disclosed in In some embodiments, the ligand in (a) is an oxygen-free ligand. In some embodiments, the ligand in (b) is an oxygen-free ligand. In some embodiments, the ligand in (a) and (b) is an alkylamine. In some embodiments, the ligand is an alkylamine selected from the group consisting of dodecylamine, oleylamine, hexadecylamine, dioctylamine, and octadecylamine. In some embodiments, the ligand in (a) is oleylamine. In some embodiments, the ligand in (b) is oleylamine. In some embodiments, the ligand in (a) and (b) is oleylamine.

In one embodiment, the sulfur source is derived from S ₈ .

In one embodiment, the temperature in (a) and (b) is about 270°C.

In some embodiments, the mixture in (b) further comprises a solvent. In some embodiments, the solvent is trioctylphosphine, dibenzyl ether, or squalane.

In some embodiments, GaX ₃ is gallium chloride, gallium fluoride, or gallium iodide. In some embodiments, GaX ₃ is gallium chloride. In some embodiments, GaX ₃ is Ga(III) chloride.

In some embodiments, the ratio of GaX ₃ for AIGS cores is 0.008-0.2 mmol GaX ₃ per mg AIGS. In some embodiments, the molar ratio of GaX ₃ to AIGS cores ranges from about 0.1 to about 30. In some embodiments, the ratio of GaX ₃ to AIGS cores is about 0.04 mmol GaX ₃ per mg AIGS.

In some embodiments, AIGS nanostructures are separated, for example by precipitation. In some embodiments, AIGS nanostructures are precipitated by addition of a non-solvent to the AIGS nanostructures. In some embodiments, the non-solvent is a toluene/ethanol mixture. Precipitated nanostructures may be further isolated by centrifugation and/or washing with a non-solvent for nanostructures.

In some embodiments, the mixture in (a) is maintained between 20°C and 100°C. In some embodiments, the mixture in (a) is maintained at about room temperature (20° C. to 25° C.).

In some embodiments, the mixture in (b) is maintained at 200° C. to 300° C. for 0.1 hour to 200 hours. In some embodiments, the mixture in (b) is maintained at 200° C. to 300° C. for about 20 hours.

Doped AIGS nanostructures

In some embodiments, AIGS nanostructures are doped. In some embodiments, the dopant of the nanocrystal core includes a metal, including one or more transition metals. In some embodiments, the dopant is Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Tc, Re, Fe, Ru, Os, Co, Rh, Ir, Ni, Pd, Pt, It is a transition metal selected from the group consisting of Cu, Ag, Au, and combinations thereof. In some embodiments, the dopant includes a non-metal. In some embodiments, the dopant is ZnS, ZnSe, ZnTe, CdSe, CdS, CdTe, HgS, HgSe, HgTe, CuInS ₂ , CuInSe ₂ , AlN, AlP, AlAs, GaN, GaP, or GaAs.

In some embodiments, the core is purified by precipitation from a non-solvent. In some embodiments, AIGS nanostructures are filtered to remove sediment from the core solution.

Nanostructure compositions

In some embodiments, the present disclosure

(a) at least one population of AIGS nanostructures; and

(b) at least one organic resin

It provides a nanostructure composition comprising a.

In some embodiments, the nanostructures have a PWL of 480-545 nm.

In some embodiments, at least 80% of the nanostructure emission is band-edge emission. In other embodiments, at least 90% of the emission is band-edge emission. In other embodiments, at least 95% of the emission is band-edge emission. In some embodiments, 92-98% of the emission is band-edge emission. In some embodiments, 93-96% of the emission is band-edge emission.

In some embodiments, the nanostructure composition further includes at least one second population of nanostructures. Nanostructures with a PWL between 480-545 nm emit green light. Additional populations of nanostructures that emit in the green, yellow, orange and/or red regions of the spectrum may be added. These nanostructures have a PWL greater than 545 nm. In some embodiments, the nanostructures have a PWL of 550-750 nm. The size of the nanostructures determines the emission wavelength. At least one second group of nanostructures is selected from the group consisting of BN, BP, BAs, BSb, AlN, AlP, AlAs, AlSb, GaN, GaP, GaAs, GaSb, InN, InP, InAs, and InSb. It may also include nanocrystals. In some embodiments, the core of the second population of nanostructures is InP nanocrystals.

organic resin

In some embodiments, the organic resin is a thermoset resin or an ultraviolet (UV) curable resin. In some embodiments, the organic resin is cured by a method that facilitates roll-to-roll processing.

Thermosetting resins require curing through an irreversible molecular crosslinking process that renders the resin insoluble. In some embodiments, the thermoset resin is an epoxy resin, phenolic resin, vinyl resin, melamine resin, urea resin, unsaturated polyester resin, polyurethane resin, allyl resin, acrylic resin, polyamide resin, polyamide-imide resin, Phenolamine condensation polymerization resin, urea melamine condensation polymerization resin, or combinations thereof.

In some embodiments, the thermoset resin is an epoxy resin. Epoxy resins are easily cured by a wide range of chemicals without generating by-products or volatile substances. Epoxy resins are also compatible with most substrates and tend to wet surfaces easily. Boyle, M.A. See “Epoxy Resins,” Composites, Volume 21, ASM Handbook, pages 78-89 (2001).

In some embodiments, the organic resin is a silicone thermoset resin. In some embodiments, the silicone thermoset is OE6630A or OE6630B (Dow Corning Corporation, Auburn, MI).

In some embodiments, a thermal initiator is used. In some embodiments, the thermal initiator is AIBN [2,2'-azobis(2-methylpropionitrile)] or benzoyl peroxide.

UV-curable resins are polymers that harden and harden quickly when exposed to specific light wavelengths. In some embodiments, the UV curable resin has a radical polymerization group as a functional group, such as a (meth)acrylyloxy group, vinyloxy group, styryl group, or vinyl group; It is a resin having cation-polymerizable groups, such as epoxy groups, thioepoxy groups, vinyloxy groups, or oxetanyl groups. In some embodiments, the UV curable resin is a polyester resin, polyether resin, (meth)acrylic resin, epoxy resin, urethane resin, alkyd resin, spiroacetal resin, polybutadiene resin, or polythiolpolyene resin.

In some embodiments, the UV curable resin is isobornyl acrylate, isobornyl methacrylate, phenoxyethyl acrylate, phenoxyethyl methacrylate, urethane acrylate, allyloxylated cyclohexyl diacrylate, Bis(acryloxy ethyl)hydroxyl isocyanurate, bis(acryloxy neopentyl glycol) adipate, bisphenol A diacrylate, bisphenol A dimethacrylate, 1,4-butanediol diacrylate, 1,4- Butanediol dimethacrylate, 1,3-butylene glycol diacrylate, 1,3-butylene glycol dimethacrylate, dicyclofentanyl diacrylate, diethylene glycol diacrylate, diethylene glycol dimethacrylate , dipentaerythritol hexaacrylate, dipentaerythritol monohydroxy pentaacrylate, di(trimethylolpropane) tetraacrylate, ethylene glycol dimethacrylate, glycerol methacrylate, 1,6-hexanediol diacrylate. 1,6-hexanediol dimethacrylate, neopentyl glycol dimethacrylate, neopentyl glycol hydroxypivalate diacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dimethacrylate phosphate Latex, polyethylene glycol diacrylate, polypropylene glycol diacrylate, tetraethylene glycol diacrylate, tetrabromobisphenol A diacrylate, triethylene glycol divinyl ether, triglycerol diacrylate, trimethylolpropane triacrylate , tripropylene glycol diacrylate, tris(acryloxyethyl)isocyanurate, phosphoric acid triacrylate, phosphoric acid diacrylate, acrylic acid propargyl ester, vinyl-terminated polydimethylsiloxane, vinyl-terminated diphenylsiloxane-dimethyl. Siloxane copolymer, vinyl-terminated polyphenylmethylsiloxane, vinyl-terminated trifluoromethylsiloxane-dimethylsiloxane copolymer, vinyl-terminated diethylsiloxane-dimethylsiloxane copolymer, vinylmethylsiloxane, monomethacryloyloxypropyl terminated It is selected from the group consisting of polydimethylsiloxane, monovinyl terminated polydimethyl siloxane, monoallyl-mono trimethylsiloxy terminated polyethylene oxide, and combinations thereof.

In some embodiments, the UV curable resin is a mercapto-functional compound that can be crosslinked with an isocyanate, epoxy, or unsaturated compound under UV curing conditions. In some embodiments, the polythiol is pentaerythritol tetra(3-mercapto-propionate) (PETMP); trimethylol-propane tri(3-mercapto-propionate) (TMPMP); glycol di(3-mercapto-propionate) (GDMP); Tris[25-(3-mercapto-propionyloxy)ethyl]isocyanurate (TEMPIC); di-pentaerythritol hexa(3-mercapto-propionate) (Di-PETMP); Ethoxylated trimethylolpropane tri(3-mercapto-propionate) (ETTMP 1300 and ETTMP 700); polycaprolacetone tetra(3-mercapto-propionate) (PCL4MP 1350); pentaerythritol tetramercaptoacetate (PETMA); trimethylol-propane trimercaptoacetate (TMPMA); or glycol dimercaptoacetate (GDMA). These compounds are sold under the trade name THIOCURE ^® by Bruno Bock (Marschacht, Germany).

In some embodiments, the UV curable resin is a polythiol. In some embodiments, the UV curable resin is ethylene glycol bis(thioglycolate), ethylene glycol bis(3-mercaptopropionate), trimethylol propane tris(thioglycolate), trimethylol propane tris(3-mer captopropionate), pentaerythritol tetrakis(thioglycolate), pentaerythritol tetrakis(3-mercaptopropionate) (PETMP), and combinations thereof. In some embodiments, the UV curable resin is PETMP.

In some embodiments, the UV curable resin is composed of polythiol and 1,3,5-triallyl-1,3,5-triazine-2,4,6 (1H,3H,5H)-trione (TTT). It is a thiol-ene formulation comprising: In some embodiments, the UV curable resin is a thiol-ene formulation comprising PETMP and TTT.

In some embodiments, the UV curable resin further includes a photoinitiator. Photoinitiators initiate crosslinking and/or curing reactions of the photosensitive material during exposure to light. In some embodiments, the photoinitiator is acetophenone-based, benzoin-based, or thioxatenone-based.

In some embodiments, the photoinitiator is a vinyl acrylate-based resin. In some embodiments, the photoinitiator is MINS-311RM (Minuta Technology Co., Ltd, Korea).

In some embodiments, the photoinitiator is IRGACURE ^® 127, IRGACURE ^® 184, IRGACURE ^® 184D, IRGACURE ^® 2022, IRGACURE ^® 2100, IRGACURE ^® 250, IRGACURE ^® 270, IRGACURE ^® 2959, IRGACURE ^® 369, IRGACURE ^® 3 69 EG, IRGACURE ^® 379, IRGACURE ^® 500, IRGACURE ^® 651, IRGACURE ^® 754, IRGACURE ^® 784, IRGACURE ^® 819, IRGACURE ^® 819Dw, IRGACURE ^® 907, IRGACURE ^® 907 FF, IRGACURE ^® Oxe01, IRGACURE ^® TPO-L, I ^RGACURE® 1173, IRGACURE ^® 1173D, IRGACURE ^® 4265, IRGACURE ^® BP, or IRGACURE ^® MBF (BASF Corporation, Wyandotte, MI). In some embodiments, the photoinitiator is TPO (2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide) or MBF (methyl benzoylformate).

In some embodiments, the weight percentage of at least one organic resin in the nanostructure composition is about 5% to about 99%, about 5% to about 95%, about 5% to about 90%, about 5% to about 80%, About 5% to about 70%, about 5% to about 60%, about 5% to about 50%, about 5% to about 40%, about 5% to about 30%, about 5% to about 20%, about 5% % to about 10%, about 10% to about 99%, about 10%, about 95%, about 10% to about 90%, about 10% to about 80%, about 10% to about 70%, about 10% to about 60%, about 10% to about 50%, about 10% to about 40%, about 10% to about 30%, about 10% to about 20%, about 20% to about 99%, about 20% to about 95%, about 20% to about 90%, about 20% to about 80%, about 20% to about 70%, about 20% to about 60%, about 20% to about 50%, about 20% to about 40% , about 20% to about 30%, about 30% to about 99%, about 30% to about 95%, about 30% to about 90%, about 30% to about 80%, about 30% to about 70%, about 30% to about 60%, about 30% to about 50%, about 30% to about 40%, about 40% to about 99%, about 40% to about 95%, about 40% to about 90%, about 40% to about 80%, about 40% to about 70%, about 40% to about 60%, about 40% to about 50%, about 50% to about 99%, about 50% to about 95%, about 50% to about 90%, about 50% to about 80%, about 50% to about 70%, about 50% to about 60%, about 60% to about 99%, about 60% to about 95%, about 60% to about 90% , about 60% to about 80%, about 60% to about 70%, about 70% to about 99%, about 70% to about 95%, about 70% to about 90%, about 70% to about 80%, about 80% to about 99%, about 80% to about 95%, about 80% to about 90%, about 90% to about 99%, about 90% to about 95%, or about 95% to about 99%.

In some embodiments, the nanostructure composition further comprises at least one monomer incorporated into a ligand that coats the AIGS surface. AIGS nanostructures containing at least one monomer incorporated into a ligand coating the AIGS surface were found to have high QY, excellent compatibility with HDDA, a common monomer used in inkjet printing inks, and excellent blue light absorption.

In some embodiments, at least one monomer is an acrylate. Examples of acrylate monomers are methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, tert-butyl methacrylate, n-amyl methacrylate, iso Amyl methacrylate, n-hexyl methacrylate, tridecyl methacrylate, stearyl methacrylate, decyl methacrylate, dodecyl methacrylate, methoxydiethylene glycol methacrylate, polypropylene glycol monomethacrylate , phenyl methacrylate, phenoxyethyl methacrylate, tetrahydrofurfuryl methacrylate, tert-butylcyclohexyl methacrylate, behenyl methacrylate, dicyclopentanyl methacrylate, dicyclopentenyloxyethyl methacrylate. Crylate, 2-ethylhexyl methacrylate, octyl methacrylate, isooctyl methacrylate, n-decyl methacrylate, isodecyl methacrylate, lauryl methacrylate, hexadecyl methacrylate, octadecyl methacrylate Crylate, benzyl methacrylate, 2-phenylethyl methacrylate, 2-phenoxyethyl acrylate, ethyl acrylate, methyl acrylate, n-butyl acrylate, 2-hydroxyethyl acrylate, 2-carboxyethyl Acrylate, acrylic acid, ethylene glycol diacrylate, 1,3-propanediol diacrylate, 1,4-bis(acryloyloxy)butane, isobornyl acrylate, tetrahydrofurfuryl acrylate, cyclic trimethyl Including, but not limited to, allpropane formal acrylate, cyclohexyl methacrylate, and 4-tert-butylcyclohexyl acrylate.

In some embodiments, the monomer is at least one of ethyl acrylate, HDDA, tetrahydrofurfuryl acrylate, tri(propylene glycol) diacrylate, 1,4-bis(acryloyloxy)butane, or isobornyl acrylate. .

Method for preparing AIGS nanostructure composition

This disclosure

(a) providing at least one population of AIGS nanostructures; and

(b) mixing the composition of (a) with at least one organic resin.

It provides a method of preparing a nanostructure composition containing a.

In some embodiments, the nanostructures have a PWL of 480-545 nm, and at least about 80% of the emission is band-edge emission. In some embodiments, at least 80% of the emission is band-edge emission. In other embodiments, at least 90% of the emission is band-edge emission. In other embodiments, at least 95% of the emission is band-edge emission. In some embodiments, 92-98% of the emission is band-edge emission. In some embodiments, 93-96% of the emission is band-edge emission.

This disclosure also:

(a) providing at least one population of AIGS nanostructures, wherein the nanostructures were prepared using a GaX ₃ (X = F, Cl or Br) precursor and an oxygen-free ligand; and

(b) mixing the composition of (a) with at least one organic resin.

It provides a method of preparing a nanostructure composition containing a.

In some embodiments, the nanostructures have a PWL of 480-545 nm, and at least about 60% of the emission is band-edge emission.

This disclosure also

(a) providing at least one population of AIGS nanostructures, wherein the nanostructures have a PWL between 480-545 nm, at least about 80% of the emission is band-edge emission, and the nanostructures have a PWL of 80-99% of the nanostructures. stands for QY; and

(b) mixing the composition of (a) with at least one organic resin.

It provides a method of preparing a nanostructure composition comprising.

In some embodiments, at least one population of nanostructures rotates between about 100 rpm and about 10,000 rpm, between about 100 rpm and about 5,000 rpm, between about 100 rpm and about 3,000 rpm, between about 100 rpm and about 1,000 rpm, between about 100 rpm and About 500 rpm, about 500 rpm to about 10,000 rpm, about 500 rpm to about 5,000 rpm, about 500 rpm to about 3,000 rpm, about 500 rpm to about 1,000 rpm, about 1,000 rpm to about 10,000 rpm, about 1,000 rpm to about 5,000 rpm, about 1,000 rpm to about 3,000 rpm, about 3,000 rpm to about 10,000 rpm, about 3,000 rpm to about 10,000 rpm, or about 5,000 rpm to about 10,000 rpm.

In some embodiments, at least one population of nanostructures is exposed from about 10 minutes to about 24 hours, from about 10 minutes to about 20 hours, from about 10 minutes to about 15 hours, from about 10 minutes to about 10 hours, from about 10 minutes to about 15 hours. About 5 hours, about 10 minutes to about 1 hour, about 10 minutes to about 30 minutes, about 30 minutes to about 24 hours, about 30 minutes to about 20 hours, about 30 minutes to about 15 hours, about 30 minutes to about 10 time, about 30 minutes to about 5 hours, about 30 minutes to about 1 hour, about 1 hour to about 24 hours, about 1 hour to about 20 hours, about 1 hour to about 15 hours, about 1 hour to about 10 hours, About 1 hour to about 5 hours, About 5 hours to about 24 hours, About 5 hours to about 20 hours, About 5 hours to about 15 hours, About 5 hours to about 10 hours, About 10 hours to about 24 hours, About 10 and is mixed with at least one organic resin for a period of time from about 20 hours to about 20 hours, from about 10 hours to about 15 hours, from about 15 hours to about 24 hours, from about 15 hours to about 20 hours, or from about 20 hours to about 24 hours.

In some embodiments, at least one population of nanostructures has a temperature range of about -5°C to about 100°C, about -5°C to about 75°C, about -5°C to about 50°C, about -5°C to about 23°C, a temperature of about 23°C to about 100°C, about 23°C to about 75°C, about 23°C to about 50°C, about 50°C to about 100°C, about 50°C to about 75°C, or about 75°C to about 100°C. mixed with at least one organic resin. In some embodiments, at least one organic resin is mixed with at least one population of nanostructures at a temperature of about 23°C to about 50°C.

In some embodiments, when more than one organic resin is used, the organic resins are added and mixed together. In some embodiments, the first organic resin is heated between about 100 rpm and about 10,000 rpm, between about 100 rpm and about 5,000 rpm, between about 100 rpm and about 3,000 rpm, between about 100 rpm and about 1,000 rpm, and between about 100 rpm and about 500 rpm. , about 500 rpm to about 10,000 rpm, about 500 rpm to about 5,000 rpm, about 500 rpm to about 3,000 rpm, about 500 rpm to about 1,000 rpm, about 1,000 rpm to about 10,000 rpm, about 1,000 rpm to about 5,000 rpm, about It is mixed with the second organic resin at a stirring rate of 1,000 rpm to about 3,000 rpm, about 3,000 rpm to about 10,000 rpm, about 3,000 rpm to about 10,000 rpm, or about 5,000 rpm to about 10,000 rpm.

In some embodiments, the first organic resin is cured for about 10 minutes to about 24 hours, about 10 minutes to about 20 hours, about 10 minutes to about 15 hours, about 10 minutes to about 10 hours, about 10 minutes to about 5 hours. , about 10 minutes to about 1 hour, about 10 minutes to about 30 minutes, about 30 minutes to about 24 hours, about 30 minutes to about 20 hours, about 30 minutes to about 15 hours, about 30 minutes to about 10 hours, about 30 minutes to about 5 hours, about 30 minutes to about 1 hour, about 1 hour to about 24 hours, about 1 hour to about 20 hours, about 1 hour to about 15 hours, about 1 hour to about 10 hours, about 1 hour to about 5 hours, from about 5 hours to about 24 hours, from about 5 hours to about 20 hours, from about 5 hours to about 15 hours, from about 5 hours to about 10 hours, from about 10 hours to about 24 hours, from about 10 hours to about and is mixed with the second organic resin for 20 hours, about 10 hours to about 15 hours, about 15 hours to about 24 hours, about 15 hours to about 20 hours, or about 20 hours to about 24 hours.

In some embodiments, the AIGS nanostructures are combined with at least one monomer incorporated into a ligand that coats the AIGS surface prior to binding to the resin. In some embodiments, the monomer is an acrylate. In some embodiments, the monomer is at least one of ethyl acrylate, HDDA, tetrahydrofurfuryl acrylate, tri(propylene glycol) diacrylate, 1,4-bis(acryloyloxy)butane, or isobornyl acrylate. .

Characteristics of AIGS nanostructures

In some embodiments, AIGS nanostructures exhibit high photoluminescence quantum yield. In some embodiments, the nanostructures have about 50% to about 99%, about 50% to about 95%, about 50% to about 90%, about 50% to about 85%, about 50% to about 80%, about 50% to about 70%, about 50% to about 60%, 60% to about 99%, about 60% to about 95%, about 60% to about 90%, about 60% to about 85%, about 60% to About 80%, about 60% to about 70%, about 70% to about 99%, about 70% to about 95%, about 70% to about 90%, about 70% to about 85%, about 70% to about 80% %, about 80% to about 99%, about 80% to about 95%, about 80% to about 90%, about 80% to about 85%, about 85% to about 99%, about 85% to about 95%, About 80% to about 85%, about 85% to about 99%, about 85% to about 90%, about 90% to about 99%, about 90% to about 95%, or about 95% to about 99% of the light. Indicates the luminescence quantum yield. In some embodiments, the nanostructures exhibit a photoluminescence quantum yield of about 82% to about 96%, about 85% to about 96%, and about 93% to about 94%.

The photoluminescence spectrum of nanostructures can cover a wide desired portion of the spectrum. In some embodiments, the photoluminescence spectrum for the nanostructures is 300 nm to 750 nm, 300 nm to 650 nm, 300 nm to 550 nm, 300 nm to 450 nm, 450 nm to 750 nm, 450 nm to 650 nm. , has an emission maximum of 450 nm to 550 nm, 450 nm to 750 nm, 450 nm to 650 nm, 450 nm to 550 nm, 550 nm to 750 nm, 550 nm to 650 nm, or 650 nm to 750 nm. In some embodiments, the photoluminescence spectrum for the nanostructures has an emission maximum between 450 nm and 550 nm.

The size distribution of nanostructures can be relatively narrow. In some embodiments, the photoluminescence spectrum of the population of nanostructures is 10 nm to 60 nm, 10 nm to 40 nm, 10 nm to 30 nm, 10 nm to 20 nm, 20 nm to 60 nm, 20 nm to 40 nm. nm, 20 nm to 30 nm, 25 nm to 60 nm, 25 nm to 40 nm, 25 nm to 30 nm, 30 nm to 60 nm, 30 nm to 40 nm, or 40 nm to 60 nm. there is. In some embodiments, the photoluminescence spectrum of the population of nanostructures can have a full width at half maximum between 24 nm and 50 nm.

In some embodiments, the nanostructures have a size of about 400 nm to about 650 nm, about 400 nm to about 600 nm, about 400 nm to about 550 nm, about 400 nm to about 500 nm, about 400 nm to about 450 nm, about 450 nm to about 650 nm, about 450 nm to about 600 nm, about 450 nm to about 550 nm, about 450 nm to about 500 nm, about 500 nm to about 650 nm, about 500 nm to about 600 nm, about 500 nm emits light having a peak emission wavelength (PWL) of from about 550 nm to about 550 nm, from about 550 nm to about 600 nm, or from about 600 nm to about 650 nm. In some embodiments, the nanostructures emit light with a PWL of about 500 nm to about 550 nm.

As a predicted value for blue light absorption efficiency, the optical density at 450 nm on a mass basis (OD ₄₅₀ /mass) was calculated by measuring the optical density of the nanostructure solution in a 1 cm path length cuvette and removing all volatiles under vacuum (<200 mTorr). It can then be calculated by dividing by the dry mass per mL of the same solution. In some embodiments, the nanostructures have an optical density at 450 nm (OD ₄₅₀ / mass) on a mass basis of between about 0.28/mg and about 0.5/mg, between about 0.28/mg and about 0.4/mg, about 0.28/mg. Between about 0.35/mg, between about 0.28/mg and about 0.32/mg, between about 0.32/mg and about 0.5/mg, between about 0.32/mg and about 0.4/mg, between about 0.32/mg and about 0.35/mg between about 0.35 mg/m and about 0.5/mg, between about 0.35/mg and about 0.4/mg, or between about 0.4/mg and about 0.5/mg.

films

Nanostructures of the invention can be embedded in a polymeric matrix using any suitable method. As used herein, the term “embedded” is used to indicate that the nanostructures are enclosed or encased in a polymer that makes up the majority of the components of the matrix. In some embodiments, the population of at least one nanostructure is appropriately uniformly distributed throughout the matrix. In some embodiments, the population of at least one nanostructure is distributed according to an application-specific distribution. In some embodiments, nanostructures are mixed in a polymer and applied to the surface of a substrate.

In some embodiments, the present disclosure

(a) a composition comprising at least one population of AIGS nanostructures and at least one ligand bound to the nanostructures; and

(b) at least one organic resin

It provides a nanostructure film layer containing.

In some embodiments, a fraction of the ligands is bound to the nanostructures. In another example, the nanostructure surface is saturated with a ligand.

In some embodiments, the nanostructures have a PWL between 480 and 545 nm.

In some embodiments, the composition comprising at least one population of AIGS nanostructures further comprises at least one monomer incorporated into a ligand that coats the AIGS surface. In some embodiments, at least one monomer is an acrylate. In some embodiments, the monomer is at least one of ethyl acrylate, HDDA, tetrahydrofurfuryl acrylate, tri(propylene glycol) diacrylate, 1,4-bis(acryloyloxy)butane, or isobornyl acrylate. .

This disclosure also

(a) providing at least one population of AIGS nanostructures; and

(b) mixing the composition of (a) with at least one organic resin.

It provides a method of preparing a nanostructure film layer containing a.

In some embodiments, nanostructures have a PWL between 480-545 nm.

In some embodiments, at least 80% of the emission is band-edge emission. In other embodiments, at least about 90% of the emission is band-edge emission. In other embodiments, at least 95% of the emission is band-edge emission. In some embodiments, 92-98% of the emission is band-edge emission. In some embodiments, 93-96% of the emission is band-edge emission.

In some embodiments, the nanostructure composition further comprises an amino ligand having Formula I:

here,

x is 1 to 100;

y is 0 to 100;

R ² is C _1-20 alkyl.

In some embodiments, x is 1 to 100, 1 to 50, 1 to 20, 1 to 10, 1 to 5, 1 to 100, 5 to 50, 5 to 20, 5 to 10, 10 to 100, 10 to 50. , 10 to 20, 20 to 100, 20 to 50, or 50 to 100. In some embodiments, x is from 10 to 50. In some embodiments, x is 10 to 20. In some embodiments, x is 1. In some embodiments, x is 19. In some embodiments, x is 6. In some embodiments, x is 10.

In some embodiments, R ² is C _1-20 alkyl. In some embodiments, R ² is C _1-10 alkyl. In some embodiments, R ² is C _1-5 alkyl. In some embodiments, R ² is -CH ₂ CH ₃ .

In some embodiments, the compound of Formula I is an amine terminated polymer commercially available from Huntsman Petrochemical Corporation. In some embodiments, the amine terminated polymer of formula (VI) has x = 1, y = 9, and R ² = -CH ₃ and is JEFFAMINE M-600 (Huntsman Petrochemical Corporation, Texas). The molecular weight of JEFFAMINE M-600 is approximately 600. In some embodiments, the amine terminated polymer of formula (III) has x = 19, y = 3, and R ² = -CH ₃ and is JEFFAMINE M-1000 (Huntsman Petrochemical Corporation, Texas). The molecular weight of JEFFAMINE M-1000 is approximately 1,000. In some embodiments, the amine terminated polymer of formula (III) has x = 6, y = 29, and R ² = -CH ₃ and is JEFFAMINE M-2005 (Huntsman Petrochemical Corporation, Texas). The molecular weight of JEFFAMINE M-2005 is approximately 2,000. In some embodiments, the amine terminated polymer of formula (III) has x = 31, y = 10, and R ² = -CH ₃ and is JEFFAMINE M-2070 (Huntsman Petrochemical Corporation, Texas). The molecular weight of JEFFAMINE M-2070 is approximately 2,000. In another embodiment, the ligand is a polyethylene glycol amine available from CreativePEGWorks, such as PEG550-amine and PEG350-amine.

In some embodiments, the nanostructured film layer is a color conversion layer.

The nanostructure composition can be applied by painting, spray coating, solvent jetting, wet coating, adhesive coating, spin coating, tape-coating, roll coating, flow coating, inkjet vapor jetting, drop casting, blade coating, mist deposition, or a combination thereof. The film may be deposited by any suitable method known in the art, including but not limited to. In some embodiments, the nanostructure composition is cured after deposition. Suitable curing methods include photocuring, such as UV curing, and thermal curing. Traditional laminated film processing methods, tape-coating methods, and/or roll-to-roll fabrication methods can be used to form the nanostructured films of the present invention. The nanostructure composition can be coated directly onto the desired layer of the substrate. Alternatively, the nanostructure composition can be formed as a solid layer as an independent element and subsequently applied onto the substrate. In some embodiments, the nanostructure composition can be deposited on one or more barrier layers.

spin coating

In some embodiments, the nanostructure composition is deposited on a substrate using spin coating. In spin coating, a small amount of material is deposited on the center of a substrate loaded into a machine called a spinner, which is typically held in place by a vacuum. High-speed rotation is applied to the substrate through a spinner, which causes centrifugal force to spread the material from the center of the substrate to the edges. While most of the material is spinning off, a small amount remains on the substrate, forming a thin film of material on the surface as spinning continues. The final film thickness is determined by the properties of the substrate and deposited material in addition to parameters selected for the spin process such as spin speed, acceleration, and spin time. For conventional films, spin speeds of 1500 to 6000 rpm are used with spin times of 10 to 60 seconds. In some embodiments, the film is deposited at very low speeds, such as less than 1000 rpm. In some embodiments, films are cast at about 300, about 400, about 500, about 600, about 700, about 800, or about 900 rpm.

Mist Deposition

In some embodiments, the nanostructure composition is deposited on a substrate using mist deposition. Mist deposition occurs at room temperature and atmospheric pressure and allows precise control over film thickness by varying process conditions. During mist deposition, the liquid source material becomes a very fine mist and is transported to the deposition chamber by nitrogen gas. The mist is then drawn to the wafer surface by the high voltage potential between the field screen and the wafer holder. Once the droplets coalesce on the wafer surface, the wafer is removed from the chamber and thermally cured to allow the solvent to evaporate. The liquid precursor is a mixture of the material to be deposited and a solvent. This is transported to the atomizer by pressurized nitrogen gas. Price, S.C. et al., “Formation of Ultra-Thin Quantum Dot Films by Mist Deposition,” ESC Transactions 11:89-94 (2007).

spray coating

In some embodiments, the nanostructure composition is deposited on a substrate using spray coating. Typical equipment for spray coating includes spray nozzles, atomizers, precursor solutions, and carrier gases. In a spray deposition process, the precursor solution is atomized into micro-sized droplets by a carrier gas or by atomization (e.g., ultrasound, air blast, or electrostatic). The droplets emerging from the atomizer are accelerated by the substrate surface through the nozzle with the help of a carrier gas that is controlled and adjusted as desired. The relative motion between the spray nozzle and the substrate is defined by the design for the purpose of total coverage on the substrate.

In some embodiments, application of the nanostructure composition further includes a solvent. In some embodiments, the solvent for application of the nanostructure composition is water, an organic solvent, an inorganic solvent, a halogenated organic solvent, or mixtures thereof. Exemplary solvents include water, D ₂ O, acetone, ethanol, dioxane, ethyl acetate, methyl ethyl ketone, isopropanol, anisole, γ-butyrolacetone, dimethylformamide, N-methylpyrrolidinone, dimethylacetamide. , hexamethylphosphoramide, toluene, dimethyl sulfoxide, cyclopentanone, tetramethylene sulfoxide, xylene, ε-caprolactone, tetrahydrofuran, tetrachloroethylene, chloroform, chlorobenzene, dichloromethane, 1,2-dichloro. Including, but not limited to, ethane, 1,1,2,2-tetrachloroethane, or mixtures thereof.

inkjet printing

Solvents suitable for inkjet printing of nanostructures are known to those skilled in the art. In some embodiments, the organic solvent is a substituted aromatic or heteroaromatic solvent described in U.S. Patent Publication No. 2018/0230321, which is incorporated herein by reference in its entirety.

In some embodiments, the organic solvent used in the nanostructure composition used as an inkjet printing formulation is defined by its boiling point, viscosity, and surface tension. The properties of organic solvents suitable for inkjet printing formulations are shown in Table 1.

In some embodiments, the organic solvent has a boiling point of about 150°C to about 350°C at 1 atmosphere. In some embodiments, the organic solvent has a temperature of about 150°C to about 350°C, about 150°C to about 300°C, about 150°C to about 250°C, about 150°C to about 200°C, about 200°C to about 350°C at 1 atmosphere. °C, about 200°C to about 300°C, about 200°C to about 250°C, about 250°C to about 350°C, about 250°C to about 300°C, or about 300°C to about 350°C. Some embodiments In fields, organic solvents have a pressure of about 1 mPa ^. s to about 15 mPa ^. It has a viscosity of s. In some embodiments, the organic solvent has a temperature of about 1 mPa ^. s to about 15 mPa ^. s, approximately 1 mPa ^. s to about 10 mPa ^. s, approximately 1 mPa ^. s to about 8 mPa ^. s, approximately 1 mPa ^. s to about 6 mPa ^. s, approximately 1 mPa ^. s to about 4 mPa ^. s, approximately 1 mPa ^. s to about 2 mPa ^. s, approximately 2 mPa ^. s to about 15 mPa ^. s, approximately 2 mPa ^. s to about 10 mPa ^. s, approximately 2 mPa ^. s to about 8 mPa ^. s, approximately 2 mPa ^. s to about 6 mPa ^. s, approximately 2 mPa ^. s to about 4 mPa ^. s, approximately 4 mPa ^. s to about 15 mPa ^. s, approximately 4 mPa ^. s to about 10 mPa ^. s, approximately 4 mPa ^. s to about 8 mPa ^. s, approximately 4 mPa ^. s to about 6 mPa ^. s, approximately 6 mPa ^. s to about 15 mPa ^. s, approximately 6 mPa ^. s to about 10 mPa ^. s, approximately 6 mPa ^. s to about 8 mPa ^. s, approximately 8 mPa ^. s to about 15 mPa ^. s, approximately 8 mPa ^. s to about 10 mPa ^. s, or about 10 mPa ^. s to about 15 mPa ^. It has a viscosity of s.

In some embodiments, the organic solvent has a surface tension of about 20 dyne/cm to about 50 dyne/cm. In some embodiments, the organic solvent has a density of about 20 dyne/cm to about 50 dyne/cm, about 20 dyne/cm to about 40 dyne/cm, about 20 dyne/cm to about 35 dyne/cm, about 20 dyne/cm. to about 30 dyne/cm, from about 20 dyne/cm to about 25 dyne/cm, from about 25 dyne/cm to about 50 dyne/cm, from about 25 dyne/cm to about 40 dyne/cm, from about 25 dyne/cm to about 35 dyne/cm, about 25 dyne/cm to about 30 dyne/cm, about 30 dyne/cm to about 50 dyne/cm, about 30 dyne/cm to about 40 dyne/cm, about 30 dyne/cm to about 35 dyne /cm, from about 35 dyne/cm to about 50 dyne/cm, from about 35 dyne/cm to about 40 dyne/cm, or from about 40 dyne/cm to about 50 dyne/cm.

In some embodiments, the organic solvent used in the nanostructure composition is an alkylnaphthalene, alkoxynaphthalene, alkylbenzene, aryl, alkyl-substituted benzene, cycloalkylbenzene, C ₉ -C ₂₀ alkane, diarylether, alkyl benzoate. , aryl benzoate, or alkoxy-substituted benzene.

In some embodiments, the organic solvent used in the nanostructure composition is 1-tetralone, 3-phenoxytoluene, acetophenone, 1-methoxynaphthalene, n-octylbenzene, n-nonylbenzene, 4-methylaniline. Sol, n-decylbenzene, p-diisopropylbenzene, pentylbenzene, tetralin, cyclohexylbenzene, chloronaphthalene, 1,4-dimethylnaphthalene, 3-isopropylbiphenyl, p-methylcumene, dipentylbenzene , o-diethylbenzene, m-diethylbenzene, p-diethylbenzene, 1,2,3,4-tetramethylbenzene, 1,2,3,5-tetramethylbenzene, 1,2,4,5 -Tetramethylbenzene, butylbenzene, dodecylbenzene, 1-methylnaphthalene, 1,2,4-trichlorobenzene, diphenyl ether, diphenylmethane, 4-isopropylbiphenyl, benzyl benzoate, 1,2- Non-(3,4-dimethylphenyl)ethane, 2-isopropylnaphthalene, dibenzyl ether, or a combination thereof. In some embodiments, the organic solvent used in the nanostructure composition is 1-methylnaphthalene, n-octylbenzene, 1-methoxynaphthalene, 3-phenoxytoluene, cyclohexylbenzene, 4-methylanisole, n-decyl Benzene, or a combination thereof.

In some embodiments, the organic solvent is an anhydrous organic solvent. In some embodiments, the organic solvent is a substantially anhydrous organic solvent.

In some embodiments, the organic solvent is a non-volatile monomer or combination of monomers selected from the list provided above.

In some embodiments, the weight percentage of organic solvent in the nanostructure composition is from about 70% to about 99%. In some embodiments, the weight percentage of organic solvent in the nanostructure composition is about 70% to about 99%, about 70% to about 98%, about 70% to about 95%, about 70% to about 90%, about 70% to about 85%, about 70% to about 80%, about 70% to about 75%, about 75% to about 99%, about 75% to about 98%, about 75% to about 95%, about 75% to about 90%, about 75% to about 85%, about 75% to about 80%, about 80% to about 99%, about 80% to about 98%, about 80% to about 95%, about 80% to about 90%, about 80% to about 85%, about 85% to about 99%, about 85% to about 98%, about 85% to about 95%, about 85% to about 90%, about 90% to about 99% , about 90% to about 98%, about 90% to about 95%, about 95% to about 99%, about 95% to about 98%, or about 98% to about 99%. In some embodiments, the weight percentage of organic solvent in the nanostructure composition is about 95% to about 99%.

In some embodiments, the composition for inkjet printing further includes a monomer incorporated into the ligand that coats the AIGS surface. In some embodiments, the monomer is an acrylate. In some embodiments, the monomer is ethyl acrylate, HDDA, tetrahydrofurfuryl acrylate, tri(propylene glycol) diacrylate, 1,4-bis (incorporated into the ligand coating the AIGS surface liloyloxy). At least one of butane or isobornyl acrylate. It has been discovered that the use of monomers in inkjet compositions provides better compatibility of AIGS nanostructures in inkjet compositions, improves QY, and improves blue light absorption.

film curing

In some embodiments, the compositions are heat cured to form a nanostructure layer. In some embodiments, the compositions are cured using UV light. In some embodiments, the nanostructure composition is coated directly onto the barrier layer of the nanostructure film, and an additional barrier layer is subsequently deposited on the nanostructure layer to form the nanostructure film. A support substrate may be employed beneath the barrier film for additional strength, stability, and coating uniformity, and to prevent material inconsistency, air bubble formation, and wrinkling or folding of the barrier layer material or other materials. Additionally, one or more barrier layers are deposited on the nanostructure layer to seal the material between the top and bottom barrier layers. Suitably, the barrier layers can be deposited as a laminate film, optionally sealed or further processed, followed by incorporation of the nanostructured film into the particular lighting device. As will be appreciated by those skilled in the art, the nanostructure composition deposition process may include additional or altered components. Such embodiments would allow in-line process tuning of nanostructure emission properties such as brightness and color (e.g., to tune quantum film white point) as well as nanostructure film thickness and other characteristics. Additionally, these embodiments will allow periodic testing of nanostructured film properties during fabrication, and any necessary toggling to achieve precise nanostructured film properties. This testing and adjustment can also be accomplished without changing the mechanical configuration of the process line, as a computer program can be employed to electronically vary the respective amounts of mixtures to be used in forming the nanostructured film.

It was discovered that nanostructure films with high PCE can be obtained when the films are processed without exposure of the AIGS nanocrystals to blue or UV light before providing an oxygen-free environment for the nanostructures. The oxygen-free environment is

(a) Encapsulating the film with an oxygen barrier prior to heat treatment and/or exposure to blue light for PCE measurements;

(b) use of oxygen-reactive materials as part of the formulation during heat treatment or light exposure; and/or

(c) Temporarily blocking oxygen through the use of a sacrificial barrier layer.

It can be provided by .

In some embodiments, improvement in PCE can be achieved by any method that can form an oxygen barrier on the AIGS layer. In mass production of devices containing these AIGS-CC layers, encapsulation can be performed using deposition processes. A typical process flow in this case includes inkjet printing of the AIGS layer, followed by curing by UV irradiation, baking at 180° C. to remove volatiles, deposition of an organic planarization layer, followed by deposition of an inorganic barrier layer. Techniques used for the deposition of inorganic layers include atomic layer deposition (ALD), molecular layer deposition (MLD), chemical vapor deposition (CVD) (with or without plasma enhancement), pulsed vapor deposition (PVD), and sputtering. , or may involve metal evaporation. Other potential encapsulation methods include solution processed or printed organic layers, UV or heat curable adhesives, lamination with barrier films, etc.

In some embodiments, the film is encapsulated in an inert atmosphere. In some embodiments, the film is encapsulated in a nitrogen or argon atmosphere.

Oxygen-reactive materials include any material that is more reactive to oxygen than the AIGS nanostructure. Oxygen-reactive materials include phosphine, phosphite, metal-organic precursors, titanium nitride, tantalum nitride, etc. In some embodiments, the phosphine may be any one of C _1-20 trialkylphosphines. In one embodiment, the phosphine is trioctylphosphine. In some embodiments, the phosphite may be trialkylphosphite, alkylarylphosphite, or trialylphosphite. In some embodiments, the metal-organic precursors can be trialkylaluminum, trialkylgallium, trialkylindium, dialkylzinc, etc.

Examples of sacrificial barrier layers include polymer layers that dissolve in and can be lost in the solvent. Examples of such polymers include, but are not limited to, polyvinyl alcohol, polyvinyl acetate, and polyethylene glycol. Other examples of sacrificial barrier layers include inorganic compounds or salts such as lithium silicate, lithium fluoride, etc. Examples of solvents that can be used to cause the sacrificial layer to wash out are water, and organic solvents such as alcohols (e.g., ethanol, methanol), halocarbons (e.g., methylene chloride and ethylene chloride), aromatic hydrocarbons. (e.g. toluene xylene), aliphatic hydrocarbons (e.g. hexane, octane, octadecine) tetrahydrofuran, C _4-20 ethers such as diethyl ether, and C _2-20 esters such as , contains ethyl acetate.

Nanostructured Film Features and Embodiments

In some embodiments, nanostructured films of the present invention are used to form display devices. As used herein, display device refers to any system with an illuminated display. Such devices include devices containing liquid crystal displays (LCDs), televisions, computers, mobile phones, smart phones, personal digital assistants (PDAs), gaming devices, electronic reading devices, and digital cameras. including, but not limited to, augmented reality/virtual reality (AR/VR) glasses, light projection systems, head-up displays, etc.

In some embodiments, nanostructured films are part of a nanostructured color conversion layer.

In some embodiments, the display device includes a nanostructured color converter. In some embodiments, the display device includes a backplane; a display panel disposed on the backplane; and a nanostructure layer. In some embodiments, the nanostructure layer is disposed on the display panel. In some embodiments, the nanostructure layer includes a patterned nanostructure layer.

In some embodiments, the backplane includes a blue LED, LCD, OLED, or microLED.

In some embodiments, the nanostructure layer is disposed on the light source element. In some embodiments, the nanostructure layer includes a patterned nanostructure layer. The patterned nanostructure layer may be prepared by any method known in the art. In one embodiment, the patterned nanostructure layer is prepared by ink-jet printing of a solution of nanostructures. Suitable solvents for the solution include, without limitation, dipropylene glycol monomethyl ether acetate (DPMA), polyglycidyl methacrylate (PGMA), diethylene glycol monoethyl ether acetate (EDGAC), and propylene glycol methyl ether acetate ( PGMEA). Volatile solvents can also be used in inkjet printing because they allow for rapid drying. Volatile solvents include ethanol, methanol, 1-propanol, 2-propanol, acetone, methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate, and tetrahydrofuran. Alternatively, “solventless” inks in which AIGS nanostructures are dispersed in the ink monomers can be used for inkjet printing.

In some embodiments, AIGS nanostructures are inkjet printed with a composition that also includes at least one monomer incorporated into a ligand that coats the AIGS surface. In some embodiments, at least one monomer is an acrylate. In some embodiments, the acrylate is at least one of ethyl acrylate, tetrahydrofurfuryl acrylate, tri(propylene glycol) diacrylate, 1,4-bis(acryloyloxy)butane, or isobornyl acrylate. . It was discovered that AIGS nanostructures treated with at least one monomer during ligand exchange provide better compatibility with HDDA, a common monomer used in inkjet printing inks, and improve QY and blue light absorption.

In some embodiments, the nanostructure layer has a thickness of about 1 μm to about 25 μm. In some embodiments, the nanostructure layer has a thickness of about 5 μm to about 25 μm. In some embodiments, the nanostructure layer has a thickness of about 10 μm to about 12 μm.

In some embodiments, the nanostructure display device exhibits a PCE of at least 32%. In some embodiments, the nanostructure molded article exhibits a PCE of 32-40%. In some embodiments, the nanostructure molded article has 33-40%, 34-40%, 35-40%, 36-40%, 37-40%, 38-40%, 39-40%, 33-39%. %, 34-39%, 35-39%, 36-39%, 37-39%, 38-39%, 33-38%, 34-38%, 35-38%, 36-38%, 37-38 %, 33-37%, 34-37%, 35-37%, 36-37%, 33-36%, 34-36%, 35-36%, 33-35%, or 34-35% of PCE indicates.

In some embodiments, the optical film comprising the nanostructure layer is substantially free of cadmium. As used herein, the term “substantially free of cadmium” is intended to mean that nanostructure compositions contain less than 100 ppm by weight of cadmium. The RoHS compliance definition requires that the raw homogeneous precursor material contain no more than 0.01% (100 ppm) by weight of cadmium. Cadmium concentration can be measured by inductively coupled plasma mass spectrometry (ICP-MS) analysis and is at the parts per billion (ppb) level. In some embodiments, “substantially cadmium-free” optical films contain 10 to 90 ppm of cadmium. In other embodiments, the substantially cadmium-free optical films contain less than about 50 ppm, less than about 20 ppm, less than about 10 ppm, or less than about 1 ppm.

Nanostructure molded articles

In some embodiments, the present disclosure

(a) first barrier layer;

(b) a second barrier layer; and

(c) a nanostructure layer between the first barrier layer and the second barrier layer, wherein the nanostructure layer is a population of nanostructures comprising AIGS nanostructures; and the nanostructure layer comprising at least one organic resin.

It provides a nanostructure molded article containing a.

In some embodiments, nanostructures have a PWL between 480-545 nm.

In some embodiments, at least 80% of the emission is band-edge emission. In other embodiments, at least 90% of the emission is band-edge emission. In other embodiments, at least 95% of the emission is band-edge emission. In some embodiments, 92-98% of the emission is band-edge emission. In some embodiments, 93-96% of the emission is band-edge emission. In some embodiments, the nanostructure molded article exhibits a PCE of at least 32%. In some embodiments, the nanostructure molded article exhibits a PCE of 32-40%. In some embodiments, the nanostructure molded article has 33-40%, 34-40%, 35-40%, 36-40%, 37-40%, 38-40%, 39-40%, 33-39%. %, 34-39%, 35-39%, 36-39%, 37-39%, 38-39%, 33-38%, 34-38%, 35-38%, 36-38%, 37-38 %, 33-37%, 34-37%, 35-37%, 36-37%, 33-36%, 34-36%, 35-36%, 33-35%, or 34-35% of PCE indicates.

barrier layers

In some embodiments, the nanostructure molded article includes one or more barrier layers disposed on one or both sides of the nanostructure layer. A suitable barrier layer protects the nanostructure layer and the nanostructure molded article from environmental conditions such as high temperature, oxygen and moisture. Suitable barrier materials include non-yellowing, transparent optical materials that are hydrophobic, chemically and mechanically compatible with the nanostructure molded article, exhibit photo- and chemical-stability, and can withstand high temperatures. In some embodiments, one or more barrier layers are index-matched to the nanostructure molded article. In some embodiments, the matrix material and one or more adjacent barrier layers of the nanostructure molded article are index-matched to have similar refractive indices such that a majority of the light that transmits through the barrier layer toward the nanostructure molded article is directed from the barrier layer. Allow to penetrate through the nanostructure layer. This index-matching reduces optical losses at the interface between the barrier and matrix materials.

Barrier layers are suitably solid materials and may be cured liquids, gels, or polymers. Barrier layers may include flexible or non-flexible materials depending on the specific application. Barrier layers are generally planar layers and, depending on the particular lighting application, may include any suitable shape and surface area configuration. In some embodiments, one or more barrier layers will be compatible with laminate film processing techniques, whereby the nanostructure layer is disposed on at least the first barrier layer and at least the second barrier layer on the side opposite the nanostructure layer. is disposed on the nanostructure layer of to form a nanostructure molded article according to one embodiment of the present invention. Suitable barrier materials include any suitable barrier materials known in the art. For example, suitable barrier materials include glasses, polymers, and oxides. Suitable barrier layer materials include polymers such as polyethylene terephthalate (PET); oxides such as silicon oxide, titanium oxide, or aluminum oxide (eg, SiO ₂ , Si ₂ O ₃ , TiO ₂ , or Al ₂ O ₃ ); and suitable combinations thereof. In some embodiments, each barrier layer of the nanostructure molded article has a different layer such that the multilayer barrier eliminates or reduces pinhole defect alignment in the barrier layer to provide an effective barrier to oxygen and moisture penetration into the nanostructure layer. It includes at least two layers comprising the material or composition. The nanostructure layer may include any suitable material or combination of materials and any suitable number of barrier layers on either one or both sides of the nanostructure layer. The material, thickness, and number of barrier layers will depend on the particular application and will be appropriately selected to maximize the brightness and barrier protection of the nanostructure layer while minimizing the thickness of the nanostructure molded article. In some embodiments, each barrier layer comprises a laminate film, and in some embodiments a dual laminate film, wherein the thickness of each barrier layer is adjusted to eliminate wrinkling in roll-to-roll or laminate manufacturing processes. Thick enough. The number or thickness of barriers may further depend on legal toxicity guidelines in embodiments where the nanostructures contain heavy metals or other toxic materials, which may require more or thicker barrier layers. It may be possible. Additional considerations for barriers include cost, availability, and mechanical strength.

In some embodiments, the nanostructured film comprises two or more barrier layers adjacent to each side of the nanostructured layer, e.g., two or three layers on each side of the nanostructured layer or two barrier layers on each layer. do. In some embodiments, each barrier layer comprises a thin glass sheet, for example, glass sheets having a thickness of about 100 μm, less than or equal to 100 μm, or less than or equal to 50 μm.

Each barrier layer of the nanostructured film of the present invention can have any suitable thickness, which thickness will vary depending on the specific requirements and characteristics of the lighting device and application, as well as the barrier layer and nanostructure, as will be understood by those skilled in the art. It will depend on the individual film components such as layers. In some embodiments, each barrier layer can have a thickness of 50 μm or less, 40 μm or less, 30 μm or less, 25 μm or less, 20 μm or less, or 15 μm or less. In certain embodiments, the barrier layer is an oxide coating that can include materials such as silicon oxide, titanium oxide, and aluminum oxide (e.g., SiO ₂ , Si ₂ O ₃ , TiO ₂ , or Al ₂ O ₃ ). Includes. The oxide coating may have a thickness of about 10 μm or less, 5 μm or less, 1 μm or less, or 100 nm or less. In certain embodiments, the barrier includes a thin oxide coating having a thickness of about 100 nm or less, 10 nm or less, 5 nm or less, or 3 nm or less. The top and/or bottom barrier may consist of a thin oxide coating, or may include a thin oxide coating and one or more additional material layers.

Display device with nanostructure color conversion layer

In some embodiments, the invention

(a) a display panel emitting first light;

(b) a backlight unit configured to provide first light to the display panel; and

(c) a color filter comprising at least one pixel region comprising a color conversion layer.

A display device including a is provided.

In some embodiments, the color filter includes at least 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 pixel areas. In some embodiments, when blue light is incident on the color filter, red light, white light, green light, and/or blue light may be emitted through the pixel regions, respectively. In some embodiments, the color filter is a U.S. color filter. No. 9,971,076, which is incorporated herein by reference in its entirety.

In some embodiments, each pixel area includes a color conversion layer. In some embodiments, the color conversion layer includes nanostructures described herein configured to convert incident light to light of a first color. In some embodiments, the color conversion layer includes nanostructures described herein that are configured to convert incident light to blue light.

In some embodiments, the display device includes 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 color conversion layers. In some embodiments, the display device includes one color conversion layer comprising the nanostructures described herein. In some embodiments, the display device includes two color conversion layers comprising the nanostructures described herein. In some embodiments, the display device includes three color conversion layers comprising nanostructures described herein. In some embodiments, the display device includes four color conversion layers comprising nanostructures described herein. In some embodiments, the display device includes at least one red color conversion layer, at least one green color conversion layer, and at least one blue color conversion layer.

In some embodiments, the color conversion layer has a thickness of about 3 μm to about 10 μm, about 3 μm to about 8 μm, about 3 μm to about 6 μm, about 6 μm to about 10 μm, about 6 μm to about 8 μm, or has a thickness of about 8 μm to about 10 μm. In some embodiments, the color conversion layer has a thickness of about 3 μm to about 10 μm.

The nanostructure color conversion layer can be applied to painting, spray coating, solvent jetting, wet coating, adhesive coating, spin coating, tape-coating, roll coating, flow coating, inkjet printing, photoresist patterning, drop casting, blade coating, mist deposition, or The film may be deposited by any suitable method known in the art, including but not limited to combinations thereof. In some embodiments, the nanostructure color conversion layer is deposited by photoresist patterning. In some embodiments, the nanostructure color conversion layer is deposited by inkjet printing.

Compositions Comprising AIGS Nanostructures and Ligands

In some embodiments, the AIGS nanostructure composition further includes one or more ligands. Ligands include amino-ligands, poly amino-ligands, mercapto-ligands, phosphino-ligands, silane ligands as well as polymeric or oligomeric chains such as polyethylene glycol with amine and silane groups.

In some embodiments, the amino-ligand has formula I:

During the ceremony:

x is 1 to 100;

y is 0 to 100;

R ² is C _1-20 alkyl.

In some embodiments, the polyamino-ligand is a polyamino alkane, polyamine-cycloalkane, polyamino heterocyclic compound, polyamino functionalized silicone, or polyamino substituted ethylene glycol. In some embodiments, the polyamino-ligand is a C _2-20 alkane or C _2-20 cycloalkane substituted with 2 or 3 amino groups and optionally containing 1 or 2 amino groups in place of a carbon group. In some embodiments, the polyamino-ligand is ethylenediamine, 1,2-diaminopropane, 1,2-diamino-2-methylpropane, N-methyl-ethylenediamine, N-ethyl-ethylenediamine, N- Isopropyl-ethylenediamine, N-cyclohexyl-ethylenediamine, N-cyclohexyl-ethylenediamine, N-octyl-ethylenediamine, N-decyl-ethylenediamine, N-dodecyl-ethylenediamine, N,N-dimethyl- Ethylenediamine, N,N-diethyl-ethylenediamine, N,N'-diethyl-ethylenediamine, N,N'-diisopropyl ethylenediamine, N,N,N'-trimethyl-ethylenediamine, diethylenetri Amine, N-isopropyl-diethylenetriamine, N-(2-aminoethyl)-1,3-propanediamine, triethylenetetramine, N,N'-bis(3-aminopropyl)ethylenediamine, N, N'-bis(2-aminoethyl)-1,3-propanediamine, tris(2-aminoethyl)amine, tetraethylenepentamine, pentaethylene hexamine, 2-(2-amino-ethylamino)ethanol, N ,N-bis(hydroxyethyl)ethylenediamine, N-(hydroxyethyl)diethylenetriamine, N-(hydroxyethyl)triethylenetetramine, piperazine, 1-(2-aminoethyl)piperazine, 4-(2-aminoethyl)morpholine, polyethyleneimine, 1,3-diaminopropane, 1,4-diaminobutane, 1,3-diaminopentane, 1,5-diminopeman, 2,2 -Dimethyl-1,3-propanediamine, hexamethylenediamine, 2-methyl-1,5-diaminopropane, 1,7-diaminoheptane, 1,8-diaminoctane, 2,2,4-trimethyl- 1,6-hexanediamine, 2,4,4-trimethyl-1,6-hexanediamine, 1,9-diaminononane, 1,10-diaminodecane, 1,12-diaminododecane, N- Methyl-1,3-propanediamine, N-ethyl-1,3-propanediamine, N-isopropyl-1,3-propanediamine, N,N-dimethyl-1,3-propanediamine, N,N'- Dimethyl-1,3-propanediamine, N,N'-diethyl-1,3-propanediamine, N,N'-diisopropyl-1,3-propanediamine, N,N,N'-trimethyl-1 ,3-propanediamine, 2-butyl-2-ethyl-1,5-pentanediamine, N,N'-dimethyl-1,6-hexanediamine, 3,3'-diamino-N-methyl-dipropylamine , N-(3-aminopropyl)-1,3-propanediamine, spermidine, bis(hexamethylene)triamine, N,N',N"-trimethyl-bis(hexamethylene)triamine, 4-amino -1,8-octanediamine, N,N'-bis(3-aminopropyl)-1,3-propydiamine, spermine, 4,4'-methylenebis(cyclohexylamine), 1,2-dia Minocyclohexane, 1,4-diaminocyclohexane, 1,3-cyclohexane bis(methylamine), 1,4-cyclohexanebis(methylamine), 1,2-bis(aminoethoxy)ethane, 4 ,9-dioxa-1,12-dodecanediamine, 4,7,10-trioxa-1,13-tridecanediamine, 1,3-diamino-hydroxy-propane, 4,4-methylene dipiperi dine, 4-(aminomethyl)piperidine, 3-(4-aminobutyl)piperidine, or polyallylamine. In some embodiments, the polyamino-ligand is 1,3-cyclohexanebis(methylamine), 2,2-dimethyl-1,3-propanediamine, or tris(2-aminoethyl)amine.

In some embodiments, the polyamino-ligand is a polyamino heterocyclic compound. In some embodiments, the polyamino heterocyclic compound is 2,4-diamino-6-phenyl-1,3,5-triazine, 6-methyl-1,3,5-triazine-2,4- Diamine, 2,4-diamino-6-diethylamino-1,3,5-triazine, 2-N,4-N,6-N-tripropyl-1,3,5-triazine-2, 4,6-triamine, 2,4-diaminopyrimidine, 2,4,6-triaminopyrimidine, 2,5-diaminopyridine, 2,4,5,6-tetraaminopyrimidine, pyridine- 2,4,5-triamine, 1-(3-aminopropyl)imidazole, 4-phenyl-1H-imidazole-1,2-diamine, 1H-imidazole-2,5-diamine, 4-phenyl- N(1)-[(E)-phenylmethylidene]-1H-imidazole-1,2-diamine, 2-phenyl-1H-imidazole-4,5-diamine, 1H-imidazole-2,4, 5-triamine, 1H-pyrrole-2,5-diamine, 1,2,4,5-tetrazine-3,6-diamine, N,N'-dicyclohexyl-1,2,4,5-tetra gin-3,6-diamine, N3-propyl-1H-1,2,4-triazole-3,5-diamine, or N,N'-bis(2-methoxybenzyl)-1H-1,2, 4-Triazole-3,5-diamine.

In some embodiments, the polyamino-ligand is a polyamino functionalized silicone. In some embodiments, the polyamino functionalized silicone is one of the following:

In some embodiments, the polyamino-ligand is polyamino-substituted ethylene glycol. In some embodiments, the polyamino substituted ethylene glycol is 2-[3-amino-4-[2-[2-amino-4-(2-hydroxyethyl)phenoxy]ethoxy]phenyl]ethanol, 1 ,5-diamino-3-oxapentane, 1,8-diamino-3,6-dioxaoctane, bis[5-chloro-1H-indole-2-YL-carbonyl-aminoethyl]-ethylene glycol, Amino-PEG8-t-Boc-hydrazide, or 2-(2-(2-ethoxyethoxy)ethoxy)ethanamine.

In some embodiments, the mercapto-ligand is (3-mercaptopropyl)triethoxysilane, 3,6-dioxa-1,8-octanedithiol; 6-mercapto-1-hexanol; They are mercapto succinic acid, mercapto undecanoic acid, mercapto hexanoic acid, mercapto propionic acid, mercapto acetic acid, cysteine, methionine and mercapto poly(ethylene glycol).

In some embodiments, the silane-ligand is an aminoalkyltrialkoxysilane or a thioalkyltrialkoxysilane. In some embodiments, the aminoalkyltrialkoxysilane is 3-aminopropyl)triethoxysilane or 3-mercappropyl)triethoxysilane.

In some embodiments, the ligand is an amino-polyalkylene oxide (e.g., about m.w. 1000); (3-aminopropyl)trimethoxysilane); (3-mercaptopropyl)triethoxysilane; DL-α-lipoic acid; 3,6-dioxa-1,8-octanedithiol; 6-mercapto-1-hexanol; Methoxypolyethylene glycol amine (about m.w. 500); poly(ethylene glycol) methyl ether thiol (about m.w. 800); diethyl phenylphosphonite; Dibenzyl N,N-diisopropylphosphoramidite; di-tert-butyl N,N-diisopropylphosphoramidite; tris(2-carboxyethyl)phosphine hydrochloride; poly(ethylene glycol) methyl ether thiol (ca. m.w. 2000); Methoxypolyethylene glycol amine (about m.w. 750); acrylamide; and polyethyleneimine.

Particular combinations of ligands include amino-polyalkylene oxide (about m.w. 1000) and methoxypolyethylene glycol amine (about m.w. 500); Amino-polyalkylene oxide (about m.w. 1000) and 6-mercapto-1-hexanol; Amino-polyalkylene oxide (about m.w. 1000) and (3-mercaptopropyl)triethoxysilane; and 6-mercapto-1-hexanol and methoxypolyethylene glycol amine (about m.w. 500); It includes, and provides excellent dispersibility and thermal stability. See Example 9.

Films comprising AIGS nanostructures and polyamino ligands exhibit higher film photo conversion efficiency (PCE) and less wrinkling compared to AIGS containing films without polyamino ligands and compared to mono-amino ligands. , indicating less peeling of the film. Accordingly, compositions comprising AIGS-polyamino-ligand are particularly suitable for use in nanostructured color conversion layers.

The following examples illustrate and do not limit the products and methods described herein. Appropriate variations and modifications to various conditions, formulations, and other parameters commonly encountered in the field and apparent to those skilled in the art upon consideration of this disclosure are within the spirit and scope of the present invention.

Examples

Example 1: AIGS Core Synthesis

Sample ID 1 was prepared using the following typical synthesis of an AIGS core: 4 mL of 0.06 M CH ₃ CO₂Ag in oleylamine, 1 mL of 0.2 M InCl ₃ in ethanol, 1 mL of 0.95 M sulfur in oleylamine, and 0.5 mL. Dodecanethiol was injected into a flask containing 5 mL of degassed octadecene, 300 mg of trioctylphosphine oxide, and 170 mg of gallium acetylacetonate. The mixture was heated to 40° C. for 5 minutes, then the temperature was raised to 210° C. and held for 100 minutes. After cooling to 180° C., 5 mL trioctylphosphine was added. The reaction mixture was transferred to the glovebox and diluted with 5 mL toluene. The final AIGS product was precipitated by adding 75 mL ethanol, centrifuged, and redispersed in toluene. Sample IDs 2 and 3 were also prepared using this method. The optical properties of the AIGS core were measured and summarized in Table 2 below. AIGS core size and morphology were characterized by transmission electron microscopy (TEM).

Example 2: AIGS nanostructures with ion exchange treatment

Sample ID 4 was prepared using the following typical ion exchange treatment: 2 mL of 0.3 M gallium oleate solution in octadecene and 12 mL oleylamine were introduced to the flask and degassed. The mixture was heated to 270 °C. A premixed solution of 1 mL of 0.95 M sulfur solution in oleylamine and 1 mL of isolated AIGS cores (15 mg/mL) was co-injected. The reaction was stopped after 30 minutes. The final product was transferred to a glovebox, washed with toluene/ethanol, centrifuged, and redispersed in toluene. Sample IDs 4-8 were also prepared using this method. The optical properties of the AIGS nanostructures prepared in this way are summarized in Table 3. Ion exchange with gallium ions resulted in almost complete band-edge emission. An increase in average particle size was observed by TEM.

Example 3: Gallium halide and trioctylphosphine ion exchange treatment

A room temperature ion exchange reaction with AIGS nanostructures was performed by adding a solution of GaI ₃ in trioctylphosphine (0.01 to 0.25 M) to the AIGS QDs and keeping them at room temperature for 20 hours. This treatment resulted in significant enhancement of band-edge emission, summarized in Table 4, while substantially maintaining peak wavelength (PWL).

Composition changes before and after GaI ₃ addition were monitored by inductively coupled plasma atomic emission spectroscopy (ICP-AES) and energy dispersive X-ray spectroscopy (EDS), as summarized in Table 4. Composite images of the distribution of In and Ga elements before and after GaI ₃ /TOP treatment showed a radial distribution of In versus Ga, such that ion exchange treatment resulted in a larger amount of gallium near the surface and a smaller amount of gallium in the center of the nanostructure. This indicates that a gradient of .

Example 4: AIGS ion exchange treatment using an oxygen-free Ga source

Samples IDs 14 and 15 were prepared using the following typical treatment of AIGS nanoparticles using an oxygen-free Ga source: to 8 mL of degassed oleylamine, 400 mg of GaCl ₃ dissolved in 400 μL toluene was added. , 40 mg of AIGS core was added, followed by 1.7 mL of 0.95 M sulfur in oleylamine. After heating to 240° C., the reaction was maintained for 2 hours and then cooled. The final product was transferred to a glovebox, washed with toluene/ethanol, centrifuged, and dispersed in toluene. Sample IDs 15 and 16 were also prepared using this method. Sample IDs 11-13 were prepared using the method of Example 2. The optical properties of the treated AIGS materials are shown in Table 5.

As shown in Table 5, when using oleylamine as a solvent, the quantum yield of the processed AIGS nanostructures can be improved by using Ga(III) chloride instead of Ga(III) acetylacetonate or gallium oleate. there is. The final material ion exchanged using Ga(III) chloride provided similar size and similar band-edges to capture the emission properties as the starting nanostructure. Therefore, the increase in quantum yield (QY) is not simply due to an increase in the trap emission component. Additionally, unexpectedly, when Ga(III) iodide was used instead of Ga(III) chloride, the AIGS nanostructures appeared to dissolve in the reaction mixture and no ion exchange occurred.

High-resolution TEM using energy-dispersive This indicates that while A results from the process where In is exchanged from the AIGS structure and replaced by Ga, Ag is present throughout the entire structure rather than growing a separate layer of GS. This may also contribute to the improved quantum yield of the nanostructures due to less strain.

Example 5: AIGS core from hot injection of preformed Ag ₂ S nanostructures mixed with preformed In-Ga reagent

To prepare Ag ₂ S nanostructures, under N ₂ atmosphere, 0.5 g of AgI and 2 mL of oleylamine are added to a 20 mL vial and stirred at 58 °C until a clear solution is obtained. In a separate 20 mL vial, 9 mL of 0.95 M sulfur in oleylamine and 5 mL DDT were mixed. The DDT + S-OYA mixture is added to the AgI solution and stirred at 58 °C for 10 min. The obtained Ag ₂ S nanoparticles were used without washing.

To prepare the In-Ga reagent mixture, 1.2 g Ga (acetylacetonate) ₃ , 0.35 g InCl ₃ , 2.5 mL oleylamine, and 2.5 mL ODE were charged to a 100 mL flask. Under N ₂ atmosphere, it was heated to 210°C and maintained for 10 minutes. An orange and viscous product was obtained.

To form AIGS nanoparticles, 1.75 g of TOPO, 23 mL of oleylamine and 25 mL of ODE were added to a 250 mL flask under N ₂ . After degassing under vacuum, this solvent mixture is heated to 210° C. over 40 minutes. In a 40 mL vial, Ag ₂ S and the In-Ga reagent mixture from above were mixed at 58° C. and transferred to a syringe. The Ag-In-Ga mixture was then injected into the solvent mixture at 210° C. and kept for 3 hours. After cooling to 180° C., 5 mL trioctylphosphine was added. The reaction mixture was transferred to the glovebox and diluted with 50 mL toluene. The final product was precipitated by adding 150 mL ethanol, centrifuged, and redispersed in toluene. The AIGS nanostructure was then ion exchanged by the method described in Example 4. The optical properties of materials prepared by this method at the scale-up up to 24x described above are shown in Table 6.

Example 7 Repeated gallium ion exchange improves the photoluminescence stability of AIGS nanostructures

7.1 First ion exchange process

Oleylamine (OYA, 2.5 L) was degassed under vacuum at 40° C. for 40 minutes. AIGS nanostructures (25.4 g in toluene) are added, followed by GaCl ₃ (minimum 127 g in toluene) and sulfur dissolved in OYA (0.95 M, 570 mL). The mixture was heated to 240° C. over 40 minutes and held for 4 hours. After cooling, the mixture is diluted with 1 volume of toluene. After centrifugation to remove some by-products, the material was washed with 2 volumes of ethanol, collected by centrifugation, and redissolved in toluene. After secondary washing, the nanostructures are dissolved in heptane for storage.

7.2 Second ion exchange process

Oleylamine (OYA, 960 mL) is degassed under vacuum at 40° C. for 20 minutes. For example, AIGS ion exchanged nanostructures from Example 7.1 (12 g in heptane) were added to OYA, followed by GaCl ₃ (22.5 g in minimal volume of toluene), then added to OYA (0.95 M, 100 mL). Add dissolved sulfur. The mixture was heated to 240° C. over 40 minutes and held for 3 hours. After cooling, the mixture is diluted with 1 vol toluene, then washed (precipitated with 1.6 vol ethanol, centrifuged) and redispersed in toluene or heptane as required. When performing ligand exchange for the ink formulation, an additional ethanol wash is applied and the QDs are redispersed in heptane.

7.3 Alternative Second Ion Exchange Process

Oleylamine (15 mL) was degassed under vacuum at 60° C. for 20 minutes. GaCl ₃ (360 mg in minimal volume of toluene) is added to OYA, followed by AIGS (200 mg in heptane), e.g. from Example 7.1, followed by sulfur (0.95 M, 1.6 mL) dissolved in OYA. do. The mixture was heated to 240° C. over 40 minutes and held for 3 hours. After cooling, the mixture is washed as described in Example 7.1.

7.4 Alternative second ion exchange process

This example was performed as described for Example 7.3 but at 3x scale.

7.5 Alternative second ion exchange process

Oleylamine (10 mL) and oleic acid (5 mL) were degassed under vacuum at 90° C. for 20 minutes. (Ga(NMe ₃ ) ₃ ) ₂ (206 mg) and GaCl ₃ (minimum volume of 180 mg in toluene) were added, followed by AIGS (200 mg in heptane), e.g. from Example 7.1. After heating to 130° C., TMS ₂ S (0.65 mL of 50% solution in ODE) was added over 20 minutes and the mixture was maintained for 2.5 hours. After cooling, washing the mixture was described in Example 7.1.

7.6 Results

The AIGS nanostructure underwent an ion exchange process in which In was exchanged for Ga. The higher temperature (240 °C v. 210 °C) used in this process compared to core growth induces ripening, so that the average size is larger than that of the unprocessed nanostructures. Nanostructures do not have well-differentiated shell structures. This can be observed in cross-sectional TEM elemental mapping. The lack of a higher band gap shell is expected to limit the maintenance of photoluminescence of these materials during film processing.

After the second ion exchange process, the average TEM size did not increase (Figures 2A-2C), but TEM elemental mapping showed that a more pronounced gradient developed for the Ga-rich (higher band gap) region in the QDs.

Elemental compositions for single and multiple ion exchange processes are shown in Table 7. Values are the average of 10-20 samples from Examples 7.1 and 7.2.

The properties of the ion exchanged AIGS nanostructures are presented in Table 8. Metal ratios are molar ratios determined by ICP.

The film PCE maintained after UV curing and 180° C. bake was significantly improved by the second ion exchange process as shown in Table 9. This is believed to be due to a process that increases the Ga concentration in the outer layer of the nanostructure, leading to a gradient toward a higher bandgap region introduced by ion exchange.

Example 8 - Compositions Comprising AIGS Nanostructures and Polyamino-Ligands

abbreviation

· Jeffamine - Jeffamine M-1000

· HDDA - 1-6 hexanediol diacrylate

· Bismethylamine - 1,3 cyclohexane bismethylamine

· PCE - Photon Conversion Effect

The crude AIGS QD growth solution was purified by washing with ethanol and redispersing in heptane (solution 1). 6-Mercapto-1-hexanol was added to solution 1, heated at 50° C. for 30 min, washed with ethanol and redispersed in heptane (solution 2). 2 μL of 6-mercapto-1-hexanol was added per 100 mg of QD inorganic solid. Jeffamine and HDDA were added to Solution 2 for the ligand exchange stage, heated at 80° C. for 1 hour, precipitated with heptane, and redispersed into HDDA (Solution 3). 83 mg of Jeffamine was added per 100 mg of QD inorganic solid. 0.42 g of HDDA was added per 100 mg of QD inorganic solid. Solution 3 and HDDA were added to an inkjet ink composition containing 10% by weight TiO ₂ and 90% by weight of monomer. The ink jet formulation has a composition of 10 wt% QD inorganic mass, 4 wt% TiO ₂ , and the remaining 86 wt% comprising ligands (bound and unbound), HDDA, monomers, photoinitiators, and QD solution. It is a combination of other miscellaneous organic matter left over from This ink formulation was Solution 4.

The polyamino ligand bismethylamine (50 mg of bismethylamine per 100 mg of QD inorganic solid) was added to Solution 4, and the composition was then cast as a film.

film casting

Solution 4 was spin coated onto a 2" x 2" glass substrate. The film was cured with a UV LED curing lamp. Afterwards, the film light conversion efficiency (PCE), a measure of brightness, was tested. The film was then baked with a hot plate set at 180°C for 30 minutes, slightly elevated above the hot plate. Alternatively, the films were baked with a hot plate set at 180°C for 10 minutes in direct contact with the hot place surface.

The film PCE was then tested. A 1" x 1" masked array of blue 448 nm LEDs provided the excitation source for the film. An integration sphere was placed on top of the film and connected to a fluorometer. See Figures 3A and 3B. PCE was obtained by analyzing the collected spectra.

PCE is the ratio of the number of green photons in forward emission to the number of blue photons generated by the test platform. Although the emission spectrum from 484 nm to 700 nm is used to calculate PCE, green emission is expected to have a peak wavelength between 484 and 545 nm, with the majority of the emission below 588 nm. PCE, LRR and film morphology are shown in Table 10. Unexpectedly, the presence of the ligands 1,3-cyclohexanebis(methylamine), tris(2-aminoethyl)amine and 2,2-dimethyl-1,3-propanediamine improved the 180 °C bake rate compared to films without ligands. It resulted in high retention of post-PCE, high LRR, and no wrinkles.

Figure 1 shows the effect of diamine addition on film morphology. The films from left to right in Figure 1 included: no additives (no wrinkling); 2,2-dimethyl-1,3-propanediamine (diamine, non-wrinkling); Cyclohexanemethylamine (monoamine, wrinkle forming); and tris (2-aminoethyl) amine (triamine, non-wrinkling). From left to right, the first and third films without diamine showed extensive wrinkling. On the other hand, the second and fourth films showed no wrinkling. Unexpectedly, the use of diamino ligands in AIGS films resulted in a significant reduction in film wrinkling.

Example 9 - Testing of additional ligands for AIGS nanostructures

In this experiment, additional ligands for AIGS nanoparticles were tested for improved QY, high compatibility, and excellent thermal stability. Additionally, these ligands were evaluated for protecting AIGS nanostructures from degradation and oxidation. Additionally, combinations of ligands that could be formulated into AIGS ink compositions were tested.

Ligand exchange with these ligands was performed in organic solvents such as ethyl acetate, PGMEA, acetone, xylene, 1,2-dichlorobenzene (ODCB), butyl acetate, and diethylene glycol monoethyl ether (DGMEE).

AIGS nanostructures are composed of polymeric or oligomeric chains such as polyethylene glycol with amine and silane groups for co-passivation, and soft bases such as phosphino-, mercapto-, and combinations thereof. ) was Ligand exchanged with a Ligand containing.

Figure 4 shows quantum yield values for a number of individual ligands and AIGS nanostructures subjected to single ion exchange as described herein. In this graph, NG : Native AIGS; NG-NL1: amino-polyalkylene oxide approximately molecular weight (mw) 1000; NG-NL2: (3-aminopropyl)trimethoxysilane); NG-NL3: (3-mercaptopropyl)ethoxysilane; NG-NL4: DL-α-lipoic acid; NG-NL5: 3,6-dioxa-1,8-octanedithiol; NG-NL6: 6-mercapto-1-hexanol; NG-NL7: Methoxypolyethylene glycol amine 500; NG-NL8: poly(ethylene glycol) methyl ether thiol Mn 800; NG-NL9: diethyl phenylphosphonite; NG-NL10: Dibenzyl N,N-diisopropylphosphoramidite; NG-NL11: di-tert-butyl N,N-diisopropylphosphoramidite; NG-NL12: Tris(2-carboxyethyl)phosphine hydrochloride; NG-NL13: poly(ethylene glycol) methyl ether thiol Mn 2000; NG-NL14: Methoxypolyethylene glycol amine 750; NG-NL15: acrylamide; and NG-NL16: polyethyleneimine).

As can be seen in Figure 4, 3-mercaptopropyl)triethoxysilane (NL3), 3,6-dioxa-1,8-octanedithiol (NL5), and 6-mercapto-1-hexane Treatment of AIGS nanostructures with all(NL6) resulted in high QY (73.7%, 72.9% and 76.1%, respectively). Accordingly, the present invention provides AIGS nanostructure compositions comprising at least one mercapto-substituted ligand that provides improved QY. Mercapto-substituted ligands are believed to provide high QY by passivating the surface of AIGS nanostructures and reducing defect emission. Amino-substituted ligands also improved QY.

In this single ligand test, the polyethylene glycol amine-substituted ligands (L1, L7, L8, and L13), the thiol-substituted ligands (L3, L5, and L6), and the silane ligand (L2) were similar to the native AIGS nanostructures. It showed excellent QY compared to . And, ligands L1, L7 and L8 provided better compatibility with the monomer when dispersed in HDDA.

Figure 5 is a graph showing the QY% of various two-ligand combinations that gave improved QY% (good combination) and reduced QY% (poor combination). Surface defects can be reduced by adding thiol ligands. The combination of L6 and L7 provided better stability than the others. However, for relatively hydrophilic ink compositions, better ligands are relatively hydrophilic ligands such as methoxypolyethylene glycol amine and poly(ethylene glycol) methyl ether thiol. These thiols also improve QY by passivating surface defects.

Suitable temperatures for ligand exchange are room temperature to 120°C. The total amount of ligand in the composition may be 60% to 150% of the mass of the AIGS.

Table 11 shows the relative changes in QY, PWL, and FWHM before and after ligand exchange with multiple ligands. Table 11 shows that L6 and L7 were the most effective ligand combinations for ink formulations, especially when combined with acrylate monomers. Combinations L2 and L7, L2 and L6, and L2 and L3, L6 and L7 provided excellent dispersibility and thermal stability. See Figure 6.

Ligand combinations that provided excellent thermal stability when heated at 180 °C for 30 min in a glove box were further studied. Ligand combinations L6 and L7, L2 and L6, and L2 and L3 provided better stability than single ligand L1. See Figure 6.

Additionally, the effect of different ratios of ligand combinations on QY was studied. While the total amount of ligand was fixed, the weight ratio of the ligand was changed. The best QY was achieved with an L6 to L7 ratio of 7:3. See Figure 7. All combinations of L6 and L7 showed improved QY compared to native AIGS nanostructures except for the ratio of 9:1. Although the mixture showed a high QY, no precipitation occurred and it was difficult to purify. Mixtures of L6 and L2, L3 and L7, and L5 and L7 are excellent ligand mixtures for AIGS nanostructures. These ligand combinations include tetrahydrofurfuryl acrylate, tri(propylene glycol) diacrylate, 1,4-bis(acryloyloxy)butane, diethylene glycol ethyl ether acrylate, isobornyl acrylate, and hydroxyl acrylate. It can be used in combination with various monomers such as propyl acrylate, 2-(acryloyloxy)ethyl hydrogen succinate, and 1,6-hexanediol diacrylate.

Example 10 - Improvement of PCE in AIGS Film

In an N ₂ -filled glovebox, AIGS QDs coated with appropriate ligands were mixed into an ink containing one or more monomers, TiO ₂ scattering particles, and a photoinitiator. Films were cast by spin-coating these inks and then cured using UV irradiation. The film was then baked on a hot plate at 180°C for 30 minutes to remove any remaining volatile components. All of these processes were carried out in an inert atmosphere - in an N ₂ -filled glovebox.

Typically at this stage, the film is measured in air by placing it, with the film side up, over a blue LED light source. An integrating sphere connected to a spectrophotometer is placed on top of the QD film (see Figures 3A and 3B) and the emission spectrum of the film is captured. The measurement is repeated with a blank glass substrate (no QDs). The blue light absorption and photon conversion efficiency (PCE) of the QD film are measured using the following equations:

Blue absorption = number of blue photons transmitted through the QD film / number of incident blue photons

PCE = number of green photons (484 to 588 nm) of forward emission / number of incident blue photons

To study the effect of air and moisture during the measurements, the baked QD films were encapsulated before being removed from the N ₂ -glovebox. This was accomplished by applying a few drops of UV-curable clear adhesive onto the QD layer, then placing a glass cover slip, and curing the adhesive by UV irradiation. The QD film sealed using glass and adhesive was measured in air using the above method.

The results show that encapsulating the QD film before measurements in air is important to achieve high photon conversion efficiency (PCE). Table 12 shows results from a set of films measured with and without encapsulation. For comparison, PCE values from a typical QDCC film containing InP QDs are also shown. When encapsulated and measured, films containing AIGS nanostructures had higher post-bake PCE values than InP, at much lower QD loadings. Further improvement in PCE was achieved by irradiating the film by placing it on a blue light source (~6 mW/cm ² ) for a period of 1 hour. Additionally, QDCC films made with AIGS QDs exhibit much narrower emission (FWHM ~30 nm) compared to films made with InP QDs (FWHM 36 nm). This is the result of a lower FWHM (34 nm vs. 39 nm) for AIGS QDs in solution, combined with the use of mono- and poly-amino ligands that enable good dispersion in the ink resin.

Figure 8 shows the impact of encapsulation and blue light treatment on a much broader sample. Unexpectedly, the PCE values achieved with encapsulation were significantly higher (>32%) than without encapsulation.

Figure 9 shows the emission linewidth (FWHM) for the film after a 180°C bake step and subsequent encapsulation. The median FWHM for films baked at 180 °C is 30.5 nm, which further narrows to 30.1 nm upon encapsulation. This narrowing may be a result of the film brightening upon encapsulation.

Although the samples in this study were encapsulated using glass and adhesive, this improvement in PCE can be achieved by any method that can form an oxygen barrier on the QD layer. In mass production of devices containing these QDCC layers, encapsulation is likely to be performed using a vapor deposition process. A typical process flow in this case would include inkjet printing of the QD layer, followed by curing with UV irradiation, baking at 180 °C to remove volatiles, deposition of an organic planarization layer, and then deposition of an inorganic barrier layer. Techniques used for the deposition of inorganic layers include atomic layer deposition (ALD), molecular layer deposition (MLD), chemical vapor deposition (CVD) (with or without plasma enhancement), pulsed vapor deposition (PVD), sputtering, or may involve metal evaporation. Other potential encapsulation methods include solution processed or printed organic layers, UV or heat curable adhesives, lamination with barrier films, etc.

Example 11 - AIGS Ink Comprising Monomers Incorporated into Ligands Coating the AIGS Surface

It was found that ligand exchange (LE) of AIGS nanostructures in the presence of monomers leads to higher solution QY, better compatible ink, and better film performance compared to LE performed purely in solvent. This was proven through LE and film evaluation using 16 different media.

LE of quantum dots (QDs), such as CdSe and InP, can also be performed in organic solvents to replace native ligands with desired ligands. The resulting QDs can then be formulated into solvent-free inks by dispersing the QDs in monomers, removing the original solvent, and adding other ink components such as scattering media and photoinitiators.

This procedure can also be used for LE of AIGS nanostructures, with high maintenance of QY. However, this approach typically results in poor dispersibility of the nanostructures in the monomer when the solvent is removed. Excellent dispersibility of AIGS nanostructures in ink and efficient passivation of the nanostructure surface with ligands are required to maintain film performance through harsh processing conditions such as UV irradiation, high temperature baking, etc. Therefore, AIGS nanostructures that are ligand-exchanged using conventional processes are not suitable for QDCC applications.

Figure 10 shows ligand-exchange in various organic solvents such as acetone, PGMEA, ethyl acetate, toluene, dichloromethane (DCM), chloroform, dimethylformamide (DMF) and ethanol at two temperatures - room temperature (25°C) and 80°C. The PLQY for the prepared AIGS nanostructure is shown. Jeffamine M1000 was used as a ligand at a mass ratio of 0.8:1 to the AIGS nanostructure.

Several solvents, PGMEA, ethyl acetate, toluene and DCM were very effective in maintaining QY after LE. In particular, LE at room temperature led to a higher QY than LE at 80°C. Other solvents tested such as acetone, chloroform, DMF and ethanol resulted in lower QY.

However, as shown in Table 13 (o = transparent dispersion; Δ = cloudy dispersion), AIGS nanostructures ligand exchanged in solvent at room temperature had poor compatibility with HDDA, a common monomer used in inkjet printable inks. The AIGS nanostructured ligand exchanged at 80 °C had better compatibility with HDDA, but had lower QY. Therefore, effective LE conditions leading to high QY and good compatibility with HDDA have been difficult to find.

The LE study was repeated using a series of common monomers (shown in Table 14) as medium instead of organic solvents. LE was performed by mixing the starting AIGS nanostructures with monomers (in heptane), then adding Jeffamine M1000 and heating at 80°C.

Figure 11 shows QY after LE in the presence of monomer. In all 16 cases, QY increased upon LE and was also higher than the QY achieved through LE in organic solvent.

After LE, AIGS nanostructures were isolated and purified by precipitation in heptane, and the yield was calculated by recording the starting and final QD masses. Unlike LE in solvent, where only small changes in mass are observed, the mass of the QD ligand exchanged from the monomer increased by 30 to 100% depending on the monomer. Since most of the monomers tested were miscible with heptane and would be removed upon QD precipitation, this indicated that some amount of monomer was incorporated into the ligand coating the QD surface.

All 16 AIGS samples were dispersed in HDDA and then mixed in ink containing scattering medium and photo-initiator. Unlike the ligand-exchanged nanostructures in solvent, all 16 samples tested here showed good compatibility in HDDA. Three films were cast from each ink by spin-coating at 700, 800 and 900 rpm and then cured with UV irradiation.

As shown in Figure 12, some monomers M2, M3, M4, M5, M6, and M8 showed high film EQE and may be good LE media for AIGS QDs.

Figure 13 shows blue absorption of spun-AIGS nanostructure film at 800 RPM. M7, M10, M13, M15 and M16 provided very high blue absorption.

Example 12 Increased blue absorption with polyamino ligands

Typical film deposition processes involve a hard bake at very high temperatures, usually around 200°C, to completely remove any residual solvents and volatile components. This hard bake prevents outgassing during deposition of other layers on top of the QDCC layer. These harsh bakes sometimes result in very low EQE. Additionally, the nanostructure is damaged by high temperature or the ligand is separated from the nanostructure, resulting in aggregation. Table 15 shows typical AIGS film EQE after UV curing and after 180°C hard bake. The EQE was good, above 33% after UV curing, but dropped below 19% at 180°C for 30 minutes after hard bake. The light retention ratio (LRR), which is the ratio of the EQE after baking and the EQE before baking, was very low below 60%, which means that the film performance was further reduced by more than 40% after baking.

To overcome this high EQE loss during hard bake and the resulting low LRR, two approaches to improve LRR were tested.

To keep the AIGS nanostructures uniformly dispersed throughout the entire film and prevent agglomeration, diamine (1,3-bis(aminomethyl)cyclohexane) was added to the AIGS monomer dispersion before ink formulation. Alternatively, it can be added to the ink formulation after mixing other ink components such as scattering medium and photoinitiator in the AIGS monomer dispersion. As can be seen in Figure 14, adding diamine to the AIGS-monomer dispersion before ink formulation increased the EQE after UV curing and POB. The EQE after UV curing increased by 3% when diamine was added in an amount of 5% w/w of the AIGS inorganic mass. Adding more diamine did not further improve the EQE. The effect of diamine on improving EQE was much higher after POB. Compared to no diamine in the monomer, the EQE was improved by 5% with the addition of 5% diamine. With the addition of 30% diamine, the EQE increased from 25% to 32% and the LRR was 92%, similar to the results seen for the InP green QD film. A side effect of diamine was an increase in viscosity, as shown in Figure 15. However, for monomers such as ethyl acrylate, the ink viscosity decreased rapidly to levels below 20 cP at room temperature.

As an alternative approach to increase EQE, better AIGS surface passivation using diamines was attempted. As shown in Figure 16, the QY of the AIGS nanostructures ligand exchanged in the presence of diamine was improved by over 12% immediately after LE. It should be noted that the QY of the AIGS nanostructures was also improved after heat treatment, simulating a hard bake, at 180°C for 30 min in the presence of monomers. The QY drop after 30 minutes at 180°C became smaller as the addition of diamine for LE increased. With 50% w/w diamine in LE, the QY before and after heat treatment was almost the same, and when 70% diamine was used in LE, the QY after heat treatment was higher.

The performance of QDCC films using these AIGS nanostructures was plotted in Figure 17. Film EQE was better when diamine was used for LE compared to no diamine, and the resistance was much higher with up to 50% more diamine added. The EQE obtained with 70% diamine addition and LE was less than 30% and 50%. When higher amounts of diamine are used in LE, the amount of diamine incorporated on the AIGS surface increases, but this is suspected to reduce the amount of ligands and/or monomers on the AIGS surface. The observed decrease in QD mass after LE with diamine is likely a result of fewer ligands and/or monomers on the QD surface. This also occurs when diamines are added to the monomer for LE, which results in increased ink viscosity.

As shown in Figure 19, when these two approaches were used to improve film EQE, the effect of diamine on film EQE was highest when diamine was added in both ligand exchange and monomer dispersion. Viscosity does not necessarily depend on the total amount of diamine in the ink. The highest diamine amount sample, where diamine was used in both LE and monomer dispersions, had a medium viscosity. This viscosity was lower than when using the same amount of diamine only in LE.

EQE improvement using diamines in LE and/or monomer dispersions was tested with 1,3-bis(aminomethyl)cyclohexane, and an additional five other additives listed in Table 16. All additives had similar effects on initial EQE, with A1, A5 and A6 being slightly better than the others when added directly with monomers. However, after hard bake, A1 and A6 were the two best additives in final film EQE. Additionally, excellent EQE was obtained without using the same additives in the LE and monomer additions among the listed amines. Even when the same diamine is used in LE and monomer addition, its effect in improving EQE may be different. For example, as can be seen in Figure 23, A6 was as effective in maintaining EQE as A1 when used in monomer addition, but was not as effective as A1 when used in LE.

Although various embodiments have been described above, it should be understood that they have been presented by way of example only and not by way of limitation. It will be apparent to those skilled in the art that various changes in form and detail may be made herein without departing from the spirit and scope of the invention. Accordingly, its breadth and scope should not be limited by any of the exemplary embodiments described above, but should be defined only in accordance with the following claims and their equivalents.

All publications, patents, and patent applications mentioned in this specification are indicative of the level of skill of those skilled in the art to which this invention pertains, unless and until each individual publication, patent, or patent application is specifically and individually indicated to be incorporated by reference. To the same extent, they are incorporated herein by reference.

Claims (46)

Ag, In, Ga, and S (AIGS) nanostructures, containing at least one ligand, exceed 32% at a peak emission wavelength of 480-545 nm when excited using a blue light source with a wavelength of about 450 nm. film, showing a conversion efficiency (PCE) of According to claim 1,
The nanostructures have an emission spectrum with a full width at half maximum (FWHM) of less than 40 nm. According to claim 1,
The nanostructures have an emission spectrum with a FWHM of 24-38 nm. According to claim 1,
The nanostructures have an emission spectrum with a FWHM of 27-32 nm. According to claim 1,
The nanostructures have an emission spectrum with a FWHM of 29-38 nm. The method according to any one of claims 1 to 5,
The nanostructures have a quantum yield (QY) of 80-99.9%. According to claim 6,
The nanostructures have a QY of 85-95%. The method according to any one of claims 1 to 5,
The nanostructures have a QY of about 86-94%. The method according to any one of claims 1 to 8,
The nanostructures have an OD ₄₅₀ /mass (mL ^. mg ^1. cm ^-1 ) of 0.8 or more. According to clause 9,
The nanostructures have an OD ₄₅₀ /mass (mL ^. mg ^-1. cm ^-1 ) in the inclusive range of 0.8-2.5. According to claim 10,
The nanostructures have an OD ₄₅₀ /mass (mL ^. mg ^-1. cm ^-1 ) in the range of 0.87-1.9. The method according to any one of claims 1 to 11,
The film wherein the average diameter of the nanostructures is less than 10 nm by TEM. According to claim 12,
Films with an average diameter of approximately 5 nm. The method according to any one of claims 1 to 13,
At least about 80% of the emissions are band-edge emissions. The method according to any one of claims 1 to 13,
At least about 90% of the emission is band-edge emission. According to claim 15,
92-98% of the emission is band-edge emission. According to claim 15,
93-96% of the emission is band-edge emission. The method according to any one of claims 1 to 17,
The film of claim 1, wherein the at least one ligand is a polyamino ligand. According to claim 18,
Wherein the at least one polyamino ligand is a polyamino alkane, polyamino-cycloalkane, polyamino heterocyclic compound, polyamino functionalized silicone, or polyamino substituted ethylene glycol. According to claim 18,
The polyamino ligand is a C _2-20 alkane or C _2-20 cycloalkane substituted with 2 or 3 amino groups and optionally containing 1 or 2 amino groups in place of a carbon group. According to claim 20,
The polyamino ligand is 1,3-cyclohexanebis(methylamine), 2,2-dimethyl-1,3-propediamine, tris(2-aminoethyl)amine, or 2-methyl-1,5-diamine. Aminopentane, film. The method according to any one of claims 1 to 17,
The film according to claim 1, wherein the at least one ligand is a compound of formula I:

During the ceremony:
x is 1 to 100;
y is 0 to 100;
R ² is C _1-20 alkyl. According to claim 22,
A film with x = 19, y = 3, and R ² = -CH ₃ . The method according to any one of claims 1 to 17,
The at least one ligand is (3-aminopropyl)trimethoxysilane); (3-mercaptopropyl)triethoxysilane; DL-α-lipoic acid; 3,6-dioxa-1,8-octanedithiol; 6-mercapto-1-hexanol; Methoxypolyethylene glycol amine (about mw 500); poly(ethylene glycol) methyl ether thiol (about mw 800); diethyl phenylphosphonite; Dibenzyl N,N-diisopropylphosphoramidite; di-tert-butyl N,N-diisopropylphosphoramidite; tris(2-carboxyethyl)phosphine hydrochloride; poly(ethylene glycol) methyl ether thiol (about mw 2000); Methoxypolyethylene glycol amine (about mw750); acrylamide; or a film that is polyethyleneimine. The method according to any one of claims 1 to 17,
The at least one ligand may be amino-polyalkylene oxide (about mw 1000) and methoxypolyethylene glycol amine (about mw 500); Amino-polyalkylene oxide (about mw 1000) and 6-mercapto-1-hexanol; Amino-polyalkylene oxide (about mw 1000) and (3-mercaptopropyl)triethoxysilane; and 6-mercapto-1-hexanol and methoxypolyethylene glycol amine (about mw 500). The method according to any one of claims 1 to 25,
A film further comprising at least one organic resin. According to claim 26,
A film, wherein the at least one organic resin is cured. The method according to any one of claims 1 to 27,
The film is 5-15 μm thick. The method according to any one of claims 1 to 28,
The film further comprising at least one monomer incorporated into the at least one ligand coating the AIGS surface. According to clause 29,
The film of claim 1, wherein the at least one monomer is an acrylate. According to clause 29,
The monomer is at least one of ethyl acrylate, HDDA, tetrahydrofurfuryl acrylate, tri(propylene glycol) diacrylate, 1,4-bis(acryloyloxy)butane, or isobornyl acrylate. The method according to any one of claims 1 to 31,
A film exhibiting blue light absorption at 450 nm of greater than 95%. The method according to any one of claims 1 to 32,
The film of claim 1, wherein the AIGS nanostructures comprise a gradient from increased gallium at the surface of the nanostructures to decreased gallium at the center of the nanostructures. A method for producing the film according to any one of claims 26 to 33, comprising:
(a) providing AIGS nanostructures and at least one ligand that coats the surface of the AIGS nanostructures;
(b) mixing the AIGS nanostructures of (a) with at least one organic resin;
(c) preparing a first film comprising the mixed AIGS nanostructures, the at least one ligand coating the surface, and the at least one organic resin on a first barrier layer;
(d) curing the film; and
(e) encapsulating the first film between the first and second barrier layers.
Including,
A method of making a film, wherein the encapsulated film exhibits a photon conversion efficiency (PCE) of greater than 32% at a peak emission wavelength of 480-545 nm when excited using a blue light source with a wavelength of about 450 nm. According to claim 34,
Wherein the method is performed before the encapsulated film is exposed in air to a blue LED light source. According to claim 34,
A method of producing a film, wherein the method is carried out under an inert atmosphere. According to claim 34,
The above method is
Adding at least one oxygen-reactive material to the mixture of AIGS nanostructures and ligands in (a), adding at least one oxygen-reactive material to the mixture in (b), and/or the first film prepared in (c) forming a second film comprising at least one oxygen-reactive material on top of and/or forming a sacrificial barrier layer that temporarily blocks oxygen and/or water on the first film prepared in (c). and measuring the PCE of the film, then removing the sacrificial barrier layer.
A method of producing a film further comprising. According to claim 34,
Wherein the two barrier layers exclude oxygen and/or water. The method according to any one of claims 34 to 38,
A method of making a film, wherein the at least one ligand is a polyamino ligand. The method according to any one of claims 34 to 39,
A method of making a film, further comprising incorporating at least one monomer into the at least one ligand coating the AIGS surface. A device comprising the film of any one of claims 1 to 33. A nanostructure molded article, comprising:
(a) first conductive layer;
(b) a second conductive layer; and
(c) the film of any one of claims 1 to 33 between the first conductive layer and the second conductive layer.
A nanostructure molded article comprising: As a nanostructured color converter.
back plane;
a display panel disposed on the back plane; and
The film of any one of claims 1 to 33 disposed on the display panel.
A nanostructured color converter comprising: According to claim 43,
A nanostructured color converter, wherein the film comprises patterned AIGS nanostructures. According to claim 43,
The nanostructured color converter of claim 1, wherein the film includes AIGS nanostructures and at least one monomer incorporated into the at least one ligand coating the AIGS surface. According to claim 43,
A nanostructured color converter, wherein the backplane includes an LED, LCD, OLED or microLED.