KR102558920B1 - Manufacturing method of perovskite nano particles-polymer composite and perovskite nano particles-polymer composite using the same - Google Patents

Abstract

The present invention discloses a method for preparing a perovskite nanoparticle-polymer composite and a perovskite nanoparticle-polymer composite prepared using the same. The present invention comprises the steps of preparing a perovskite precursor solution; preparing a UV curable resin solution; preparing a perovskite nanoparticle-resin mixed solution by dropping the perovskite precursor solution into the UV curable resin solution; coating the perovskite nanoparticle-resin mixed solution on a substrate; and preparing a perovskite nanoparticle-polymer composite film by UV-curing the perovskite nanoparticle-resin mixture solution coated on the substrate.

Description

Manufacturing method of perovskite nanoparticle-polymer composite and perovskite nanoparticle-polymer composite produced through this

The present invention relates to a method for preparing a perovskite nanoparticle-polymer composite and a perovskite nanoparticle-polymer composite produced thereby, and more particularly, to a method for preparing a perovskite nanoparticle-polymer composite for synthesizing perovskite nanoparticles by a ligand-assisted reprecipitation (LARP) method using a UV curable resin solution as an anti-solvent, and a perovskite nanoparticle prepared through the same It relates to particle-polymer composites.

Currently, the mega trend of the display market is moving beyond the existing high-efficiency, high-resolution display to emotional quality display that aims to realize natural colors with high color purity. From this point of view, organic light emitting diode (OLED) devices based on organic light emitting materials have made significant progress, and inorganic quantum dot LEDs with improved color purity are being actively researched and developed as an alternative. However, both organic light-emitting materials and inorganic quantum dot light-emitting materials have inherent limitations in terms of materials.

Existing organic light emitting materials have the advantage of high efficiency, but have poor color purity due to their wide spectrum. Inorganic quantum dot light emitting bodies have been known to have good color purity, but it is difficult to control the size of quantum dots to be uniform as they go toward blue color, so there is a problem in that color purity decreases. Moreover, since inorganic quantum dots have a very deep valence band, there is a problem in that hole injection is difficult because the hole injection barrier in the organic hole injection layer is very large.

Since metal halide perovskite materials have high color purity, simple color control, and low synthesis cost, they have great potential for development as light emitting materials. In addition, since it has high color purity (full width at half maximum (FWHM) ≒ 20 nm), it is possible to implement a light emitting device closer to natural color.

Therefore, in recent years, the excellent photoelectric properties of the perovskite structure (ABX ₃ ) quantum dot compound, that is, absorption wavelength and emission wavelength controllability through anion (X ^- ) composition change, narrow emission wavelength (Full width at half maximum (FWHM) 20 nm), high-performance light emitting devices (LED), solar cell devices, etc. using characteristics such as high color purity, high charge mobility, and low manufacturing cost are being actively conducted.

Typically, such perovskite quantum dots can be prepared by two synthesis methods: a hot injection (HI) method and a ligand-assisted reprecipitation (LARP) method.

In the case of synthesizing quantum dots of CsPbBr ₃ composition, the high-temperature injection method is a method of making nanocrystals by injecting a Cs-oleate precursor made of CsCO ₃ , 1-octadecene, and oleic acid into a PbBr ₂ precursor solution made of PbBr ₂ , 1-octadecene, oleic acid, and oleylamine at high temperature.

In the ligand-assisted re-precipitation method, organic acid ligands such as PbBr ₂ , CsBr, and oleic acid, and organic ammonium ligands such as oleylamine are dissolved in dimethylformamide (DMF) or dimethylsulfooxide (DMSO), a protic solvent, and then dropped into a solvent having remarkably low solubility for PbBr ₂ and CsBr, such as toluene, to synthesize nanocrystals.

In general, since perovskite quantum dots produced through this process are weak in environmental resistance (moisture, light, heat, etc.), encapsulation is performed when they are applied to devices.

Encapsulation may be performed on the device itself, perovskite quantum dots, or both methods may be applied.

Among them, the encapsulation of perovskite quantum dots mainly uses a method of introducing a chemical substance capable of chemically and physically bonding with perovskite quantum dots or ligands, impregnating the quantum dots into a porous material, or dispersing them in a polymer medium. Recently, many studies have been conducted on the method of making a composite film by dispersing in a polymer medium, which is the latter method.

In addition, in order to manufacture blue light-emitting perovskite nanoparticles through this method, CsPbBr _x Cl _3-x mixed composition nanoparticles or CsPbBr ₃ nanoparticles having a limited quantum size through anion substitution are used, and an additional process is required for this. There is a problem.

Patent Document 1 first synthesizes quantum dots to produce a quantum dot-polymer (polymer, resin) composite, and then mixes it with a prepared polymer resin (or UV curable material) to produce a quantum dot-polymer composite. It relates to a technique.

Patent Document 1 and Non-Patent Document 1 relate to a technique of using a halide anion substitution method to prepare blue light-emitting perovskite nanoparticles, and Non-Patent Document 2 manufactures nanoparticles with limited quantum size to produce blue light-emitting perovskite nanoparticles. For this purpose, it is a technology that requires additional processes such as sonication, ligand introduction, and passivation treatment.

Therefore, Patent Document 1 includes a step of first synthesizing perovskite quantum dots to produce a quantum dot-polymer (polymer, resin) composite, and then mixing them with a prepared polymer resin (or UV curable material), so there is a problem in that the process becomes complicated, and Patent Document 1 and Non-Patent Documents 1 and 2 have a problem that requires an additional process for the synthesis and stability of anion-substituted or quantum size-limited nanoparticles to produce blue-emitting perovskite nanoparticles.

Republic of Korea Patent No. 1833718, "Display realizing natural light and its manufacturing method"

An embodiment of the present invention is a method for preparing a perovskite nanoparticle-polymer composite capable of preparing a more uniform perovskite nanoparticle-polymer composite without additional processes such as a precipitation process, a centrifugation process, and a redispersion process by synthesizing perovskite nanoparticles by a ligand-assisted reprecipitation (LARP) method using a UV curable resin solution as an anti-solvent, and a perovskite nanoparticle prepared through this It is intended to provide a particle-polymer composite.

Moreover, since additional processes such as precipitation, centrifugation, and redispersion processes are not required, an eco-friendly synthesis method is provided by excluding the use of a separate solvent.

Embodiments of the present invention provide a method for preparing a perovskite nanoparticle-polymer composite capable of synthesizing perovskite nanoparticles having a luminescent color of various wavelengths from blue to green by adjusting the temperature of a UV curable resin solution, and a perovskite nanoparticle-polymer composite prepared through this.

A method for preparing a perovskite nanoparticle-polymer composite according to an embodiment of the present invention includes preparing a perovskite nanoparticle-resin mixed solution by dropwise adding a perovskite precursor solution to a UV curable resin solution; coating the perovskite nanoparticle-resin mixed solution on a substrate; and UV-curing the perovskite nanoparticle-resin mixture solution coated on the substrate to prepare a perovskite nanoparticle-polymer composite film; includes

In the step of preparing a perovskite nanoparticle-resin mixed solution by dropwise adding the perovskite precursor solution to the UV curable resin solution, the ligand-assisted re-precipitation using the UV curable resin solution as an anti-solvent Perovskite nanoparticles may be synthesized by the LARP method.

The perovskite nanoparticles may have a structure of at least one of ABX ₃ , A ₂ BX ₄ , ABX ₄ or A _n−1 B _n X3 _n+1 (wherein A is a monovalent cation or divalent cation, B is a divalent metal cation or a trivalent metal cation, X is a monovalent anion, and n is an integer between 2 and 6).

In the step of preparing a perovskite nanoparticle-resin mixed solution by dropwise adding the perovskite precursor solution to the UV curable resin solution, the emission color of the perovskite nanoparticles may be adjusted according to the temperature of the UV curable resin solution.

The temperature of the UV curable resin solution may be 0 °C to 50 °C.

The perovskite precursor solution may include a first perovskite precursor containing a monovalent cation or a divalent cation, a second perovskite precursor containing a divalent metal cation or a trivalent metal cation, an organic acid, and an organic ligand.

The UV curable resin solution includes a prepolymer, a photoinitiator, and a solvent, and the prepolymer may include at least one of a monomer and a multifunctional group.

The UV curable resin solution may include 90% to 98% by weight of the monomer, 1% to 5% by weight of the multifunctional group, and 1% to 3% by weight of the photoinitiator, based on the total weight part.

The perovskite nanoparticle-polymer composite according to an embodiment of the present invention includes perovskite nanoparticles; and a polymer matrix surrounding the perovskite nanoparticles, wherein the polymer matrix is a UV curable polymer.

The UV curable polymer may include at least one of a (meth)acrylate-based polymer, a urethane-based polymer, an epoxy-based polymer, a vinyl-based polymer, and a silicone-based polymer.

The perovskite nanoparticles have a structure of CsPbBr ₃ and may emit blue light.

According to an embodiment of the present invention, by synthesizing perovskite nanoparticles by a ligand-assisted reprecipitation (LARP) method using a UV curable resin solution as an anti-solvent, a method for producing a perovskite nanoparticle-polymer composite capable of producing a more uniform perovskite nanoparticle-polymer composite without additional processes such as a precipitation process, a centrifugation process, and a redispersion process, and a perovskite produced through the same A nanoparticle-polymer composite may be provided.

Moreover, since additional processes such as a precipitation process, a centrifugation process, and a redispersion process are not required, an eco-friendly synthesis method can be provided by excluding the use of a separate solvent.

Embodiments of the present invention provide a method for preparing a perovskite nanoparticle-polymer composite capable of synthesizing perovskite nanoparticles having a luminescent color of various wavelengths from blue to green by adjusting the temperature of a UV curable resin solution, and a perovskite nanoparticle-polymer composite prepared through this can be provided.

1 is a flow chart showing a method for preparing a perovskite nanoparticle-polymer composite according to an embodiment of the present invention.
2 is an image showing step S120 of the method for preparing a perovskite nanoparticle-polymer composite according to an embodiment of the present invention.
3 is a schematic diagram showing a perovskite nanoparticle-polymer composite according to an embodiment of the present invention.
4 is an image showing a perovskite nanoparticle-polymer composite film prepared according to Comparative Example 2.
5 is an image showing a perovskite nanoparticle-polymer composite film prepared according to Example 1 of the present invention.
6 is an image showing a letter-shaped perovskite nanoparticle-polymer composite prepared according to Example 1 of the present invention.
7 is a graph showing the change in fluorescence according to the synthesis time in the preparation method of the perovskite nanoparticle-polymer composite according to Comparative Example 1.
8 is a graph showing the fluorescence change according to the synthesis time in the method for preparing the perovskite nanoparticle-polymer composite prepared according to Example 1 of the present invention.
9 is a graph showing the band gap according to the diameter of perovskite nanoparticles generally reported in the literature.
10 is a perovskite nanoparticle according to the temperature of a UV curable resin solution in the preparation method of the perovskite nanoparticle-polymer composite prepared according to Comparative Example 1 (d) and Examples 1 (a) to 3 (c) of the present invention. It is an image showing transmission electron microscopy (TEM) results of nanoparticles.
11 is a graph showing the luminescence intensity according to the temperature of the UV curable resin solution in the preparation method of the perovskite nanoparticle-polymer composite prepared according to Comparative Example 1 and Examples 1 to 3 of the present invention.
12 is a graph showing the X-ray diffractometer (XRD) results according to the temperature of the UV curable resin solution in the preparation method of the perovskite nanoparticle-polymer composite prepared according to Comparative Example 1 and Examples 1 to 3 of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings and the contents described in the accompanying drawings, but the present invention is not limited or limited by the embodiments.

Terminology used herein is for describing the embodiments and is not intended to limit the present invention. In this specification, singular forms also include plural forms unless specifically stated otherwise in a phrase. As used herein, "comprises" and/or "comprising" does not exclude the presence or addition of one or more other elements or steps in a stated component or step.

"Embodiments," "examples," "aspects," "examples," and the like used herein are not to be construed as preferred or advantageous over any aspect or design described.

Also, the term 'or' means 'inclusive or' rather than 'exclusive or'. That is, unless otherwise stated or clear from the context, the expression 'x employs a or b' means any one of the natural inclusive permutations.

Also, the singular expressions “a” or “an” used in this specification and claims should generally be construed to mean “one or more,” unless indicated otherwise or clear from context to refer to the singular form.

The terms used in the description below have been selected as general and universal in the related technical field, but there may be other terms depending on the development and / or change of technology, convention, preference of technicians, etc. Therefore, terms used in the following description should not be understood as limiting technical ideas, but should be understood as exemplary terms for describing the embodiments.

In addition, in certain cases, there are also terms arbitrarily selected by the applicant, and in this case, their meanings will be described in detail in the corresponding description section. Therefore, terms used in the following description should be understood based on the meaning of the term and the contents throughout the specification, not simply the name of the term.

Unless otherwise defined, all terms (including technical and scientific terms) used in this specification may be used in a meaning commonly understood by those of ordinary skill in the art to which the present invention belongs. In addition, terms defined in commonly used dictionaries are not interpreted ideally or excessively unless explicitly specifically defined.

Meanwhile, in the description of the present invention, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description will be omitted. In addition, the terminology used in this specification is a term used to appropriately express the embodiment of the present invention, which may vary according to the intention of a user or operator or customs in the field to which the present invention belongs. Therefore, definitions of these terms will have to be made based on the content throughout this specification.

1 is a flow chart showing a method for preparing a perovskite nanoparticle-polymer composite according to an embodiment of the present invention.

The method for preparing a perovskite nanoparticle-polymer composite according to an embodiment of the present invention includes preparing a perovskite nanoparticle-resin mixed solution by dropwise adding a perovskite precursor solution to a UV curable resin solution (S110), coating the perovskite nanoparticle-resin mixed solution on a substrate (S120), and UV curing the perovskite nanoparticle-resin mixed solution coated on the substrate and preparing a nanoparticle-polymer composite film (S130).

First, in the method for preparing a perovskite nanoparticle-polymer composite according to an embodiment of the present invention, a perovskite precursor solution is dropwise added to a UV curable resin solution to prepare a perovskite nanoparticle-resin mixed solution. Step (S110) is performed.

In the step of preparing a perovskite nanoparticle-resin mixed solution by dropwise adding the perovskite precursor solution to the UV curable resin solution (S110), the ligand-assisted re-precipitation using the UV curable resin solution as an anti-solvent Perovskite nanoparticles may be synthesized by the LARP method.

Therefore, in the method for preparing a perovskite nanoparticle-polymer composite according to an embodiment of the present invention, a more uniform perovskite nanoparticle-polymer composite can be prepared without additional processes such as a precipitation process, a centrifugation process, and a redispersion process, by synthesizing perovskite nanoparticles by a ligand-assisted reprecipitation (LARP) method using a UV curable resin solution as an anti-solvent.

In addition, since additional processes such as a precipitation process, a centrifugation process, and a redispersion process are not required, an eco-friendly synthesis method can be provided by excluding the use of a separate solvent.

That is, in the method for preparing a perovskite nanoparticle-polymer composite according to an embodiment of the present invention, when synthesizing perovskite nanoparticles using the LARP method in order to eliminate a conventional complicated process, a UV curable resin solution is used as an anti-solvent instead of using an anti-solvent such as toluene, and perovskite nanoparticles are synthesized using a UV curable resin solution as an anti-solvent, and a perovskite nanoparticle-polymer composite can be prepared by simply UV photocuring.

For example, when synthesizing CsPbBr ₃ perovskite nanoparticles using the LARP method, by using a photocurable prepolymer as an anti-solvent instead of toluene, which is a conventionally used anti-solvent, the synthesized CsPbBr ₃ perovskite nanoparticles-resin mixture can be coated without a separate purification process, and then a light-emitting film can be prepared through a simple UV curing treatment.

The synthesized perovskite nanoparticles may have a structure of at least one of ABX ₃ , A ₂ BX ₄ , ABX ₄ or A _n−1 B _n X3 _n+1 (wherein A is a monovalent cation or divalent cation, B is a divalent metal cation or a trivalent metal cation, X is a monovalent anion, and n is an integer between 2 and 6).

Specifically, A is formamidinium, acetamidinium, guamidinium, (CH(NH₂)₂, C_xH_2x+1(CNH₃), (CH₃NH₃)n, ((C_xH_2x+1)nNH₃)n(CH₃NH₃)n, R(NH₂)₂(Where R is an alkyl group), (C_nH_2n+1NH₃)n, (CF₃NH₃), (CF₃NH₃)n, ((C_xF_2x+1)nNH₃)n(CF₃NH₃)n, ((C_xF_2x+1)nNH₃)n, (C_nF_2n+1NH₃)_n (where n and x are integers from 1 to 100), Na, K, Rb, Cs, Fr, Ti, and derivatives thereof.

according to the embodiment. A may contain a divalent metal cation different from B.

B may include at least one of Pb, Mn, Cu, Ga, Ge, In, Al, Sb, Bi, Po, Sn, Eu, Yb, Ni, Co, Fe, Cr, Pd, Cd, Ca, and Sr.

X may include at least one of Cl, Br, and I.

Accordingly, the synthesized perovskite nanoparticles may be halide perovskite nanoparticles, and preferably, the perovskite nanoparticles may include at least one of CsPbBr ₃ , MAPbBr ₃ and FAPbBr ₃ .

Preferably, the synthesized perovskite nanoparticles have a structure of CsPbBr ₃ and may emit blue light.

The synthesized blue-emitting perovskite nanoparticles may include only a single halide rather than a halide mixture composition, and may preferably be perovskite nanoparticles containing only Br.

Therefore, the perovskite nanoparticles including the mixed composition have a stability problem due to the crystal phase change due to the interionic/interstitial size difference in the case of the mixed composition, but the perovskite nanoparticles according to an embodiment of the present invention. Perovskite nanoparticles synthesized by the method for producing a polymer composite contain only a single halide and the UV curable polymer plays a passivation role, so the manufacturing process can be simplified and color stability can be improved at the same time.

In the step of preparing a perovskite nanoparticle-resin mixed solution by dropwise adding the perovskite precursor solution to the UV curable resin solution (S110), the emission color of the perovskite nanoparticle-polymer composite may be adjusted according to the temperature of the UV curable resin solution.

Therefore, the method for preparing a perovskite nanoparticle-polymer composite according to an embodiment of the present invention controls the temperature of a UV curable resin solution to synthesize perovskite nanoparticles having emission colors of various wavelengths from blue to green (finally, a perovskite nanoparticle-polymer composite).

The temperature of the UV-curable resin solution can be adjusted while looking at the stability of the process and the wavelength of the luminescent color within the melting point and boiling point range of the UV-curable resin solution.

More specifically, the temperature of the UV curable resin solution may be -20 ℃ to 90 ℃, preferably, the temperature of the UV curable resin solution may be 0 ℃ to 50 ℃, if the temperature of the UV curable resin solution is less than 0 ℃, there is a problem that the reaction proceeds slowly, and if it exceeds 50 ℃, there is a problem that the resin composition is changed due to evaporation of the UV curable resin solution.

A technique for controlling the emission color of the perovskite nanoparticle-polymer composite according to the temperature of the UV-curable resin solution will be described in detail with reference to FIG. 2 .

The perovskite precursor solution may include a first perovskite precursor including a monovalent cation or a divalent cation, a second perovskite precursor including a divalent metal cation or a trivalent metal cation, an organic acid, and an organic ligand.

For example, CsBr may be used as the first perovskite precursor, and PbBr ₂ may be used as the second perovskite precursor.

The organic acid may include at least one of carboxylic acid and phosphonic acid.

Carboxylic acids are 4,4'-Azobis (4-cyanovaleric acid), acetic acid, 5-aminosalicylic acid, acrylic acid, L-aspentic acid, 6-broth 6-Bromohexanoic acid, Bromoacetic acid, Dichloroacetic acid, Ethylenediaminetetraacetic acid, Isobutyric acid, Itaconic acid, Maleic acid acid), r-Maleimidobutyric acid, L-Malic acid, 4-Nitrobenzoic acid, 1-Pyrenecarboxylic acid, hexanoic acid, octanoic acid, deca It is selected from decanoic acid, undecanoic acid, dodecanoic acid, hexadecanoic acid, octadecanoic acid and oleic acid, wherein the phosphonic acid is n-hexylphosphonic acid, n-octylphosphonic acid , It may include at least one of n-decylphosphonic acid, n-dodecylphosphonic acid, n-tetradecylphosphonic acid, n-hexadecylphosphonic acid, n-octadecylphosphonic acid, benzylphosphonic acid, and benzhydrylphosphonic acid.

The organic ligand may be an organic ammonium ligand having a structure of alkyl-X, and the alkyl is an acylic alkyl (C _n H 2 _{n + 1} ), a polyhydric alcohol (C _n H _{2n + 1} OH) including primary alcohol, secondary alcohol or tertiary alcohol, hexadecyl amine, 9- _{octadecenylamine} , and alkylamine (alkyl-N ), at least one of p-substituted aniline, phenyl ammonium and fluorine ammonium, and X may be at least one of Cl _, Br or I.

According to an embodiment, the perovskite precursor solution may include a protic solvent, and the protic solvent may include at least one of dimethylformamide, dimethylsulfoxide, gamma butyrolactone, acetonitrile, N-methylpyrrolidone, and isopropyl alcohol.

The UV curable resin solution may include 90% to 98% by weight of the monomer, 1% to 5% by weight of the multifunctional group, and 1% to 3% by weight of the photoinitiator, based on the total weight of the solution.

Monomers or multifunctional groups included in the prepolymer include methyl methacrylate (MMA), benzyl methacrylate (BMA), phenyl methacrylate, 2-ethylhexyl acrylate, hydroxyethyl acrylate (HEA), hydroxyethyl methacrylate (HEMA), 1,6-hexanediol acrylate (HDDA), tripropylene glycol diacrylate (TPGDA), trimethylol propane triacrylate (TMPTA), acrylic acid (AA) and 2-propenoic acid 2-carboxyethyl.

Preferably, benzyl methacrylate (BMA) may be used as the monomer, and tri-trimethylol propane triacrylate (TMPTA) may be used as the multifunctional group.

Photoinitiators are benzophenone, benzoyl methyl benzoate, acetophenone, 2,4-diethylthioxanthone, 2-chloro thioxanthone, ethyl anthraquinone, 1-hydroxycyclohexyl It may include at least one of phenyl ketone (1-Hydroxy-cyclohexyl-phenyl-ketone), diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide, and 2-hydroxy-2-methylpropiophenone.

Preferably, at least one of diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide and 2-hydroxy-2-methylpropiophenone may be used as the photoinitiator.

Thereafter, in the method for producing a perovskite nanoparticle-polymer composite according to an embodiment of the present invention, the perovskite nanoparticle-resin mixture solution is coated on the substrate (S120).

The perovskite nanoparticle-resin mixture solution may be coated by any one of spin-coating, slot printing, dip coating, and ink-jet printing, and in terms of process simplicity and cost, spin-coating or ink-jet printing is preferred, but is not limited thereto.

According to an embodiment, in the method for preparing a perovskite nanoparticle-polymer composite according to an embodiment of the present invention, a flask may be coated with a perovskite nanoparticle-resin mixture solution.

Therefore, in the method for producing a perovskite nanoparticle-polymer composite according to an embodiment of the present invention, light emitting bodies of various shapes can be prepared by UV curing the perovskite nanoparticle-resin mixture solution coated on a mold of various shapes.

Finally, in the method for producing a perovskite nanoparticle-polymer composite according to an embodiment of the present invention, the perovskite nanoparticle-polymer composite film is prepared by UV-curing the perovskite nanoparticle-resin mixture solution coated on the substrate (S130).

In step S130, the perovskite nanoparticle-resin mixture solution coated on the substrate is irradiated with ultraviolet rays to cure the prepolymer with ultraviolet rays, thereby producing a perovskite nanoparticle-polymer composite in which perovskite nanoparticles are dispersed in a UV curable polymer.

Therefore, in the method for preparing a perovskite nanoparticle-polymer composite according to an embodiment of the present invention, when the temperature of a UV curable resin solution is adjusted to 0 ° C, perovskite nanoparticles (eg, CsPbBr ₃ ) having high efficiency of blue light emission can be obtained, and UV curing can be performed to prepare a perovskite nanoparticle-composite having high efficiency of blue light emission.

As a result, compared to the blue light emitting perovskite nanoparticles using the conventional CsPbBr _x Cl _3-x mixed composition or quantum size limited CsPbBr ₃ using anion substitution, the manufacturing process is simple and the perovskite nanoparticles with improved color stability. A composite film can be prepared.

2 is an image showing step S120 of the method for preparing a perovskite nanoparticle-polymer composite according to an embodiment of the present invention.

Referring to FIG. 2, in the prior art using toluene as an anti-solvent, when synthesizing perovskite nanoparticles of CsPbBr ₃ , the emission color does not change depending on the temperature of toluene, and the perovskite nanoparticle-polymer complex emits green light. It can be seen that.

However, in the method for producing a perovskite nanoparticle-polymer composite according to an embodiment of the present invention, the emission color of the perovskite nanoparticle (finally, the emission color of the perovskite nanoparticle-polymer composite) can be adjusted according to the temperature of the UV curable resin solution.

In the method for preparing a perovskite nanoparticle-polymer composite according to an embodiment of the present invention, the diameter of the synthesized perovskite nanoparticles can be adjusted by adjusting the temperature of the UV curable resin solution. Therefore, the emission color may be changed according to the diameter of the perovskite nanoparticles.

Since the perovskite nanoparticles emit light due to the quantum confinement effect or the quantum size effect, the band gap increases as the diameter decreases below the Bohr radius due to the quantum confinement effect. Therefore, the emission color of the perovskite nanoparticles can be adjusted by shifting the emission color to blue.

The diameter of the perovskite nanoparticles may be 1 nm to 4 nm.

For example, when synthesizing perovskite nanoparticles of CsPbBr ₃ , an amorphous shape having a diameter of about 4 nm at 0° C. exhibiting a blue color can be achieved.

Since the polarity of constituent species included in the UV-curable resin solution is higher than that of toluene, the Cs ₄ PbBr ₆ crystal phase (CsBr : PbBr ₂ = 4 : 1, that is, the phase structure lacking PbBr ₂ ) (first crystal phase) and the CsPbBr ₃ crystal phase (CsBr : PbBr ₂ = 1 : 1) (second crystal) exhibiting a luminescent color are present in the perovskite nanoparticle-resin mixed solution. phase) can exist simultaneously.

That is, since the interaction between the ionic PbBr ₂ and the prepolymer is greater than the PbBr ₂ -toluene interaction, when PbBr ₂ dissolved in the perovskite precursor solution is injected into the prepolymer, a small amount of PbBr ₂ is redispersed (dissolved) in the prepolymer due to the PbBr ₂ -prepolymer interaction, resulting in stable Cs having a structure lacking PbBr ₂ (second perovskite precursor). ₄ PbBr ₆ crystal phase (first crystal phase) can be produced relatively easily.

Thereafter, a small amount of undissolved PbBr ₂ reacts with CsBr to form a small-sized (eg, 4 nm) CsPbBr ₃ amorphous phase, which may exhibit blue emission.

If the temperature of the UV curable resin solution is increased, the size and crystallinity of the synthesized CsPbBr ₃ crystal phase (second crystal phase) increases as the temperature of the UV curable resin solution including the prepolymer increases, and the emission color may change from blue to green.

Therefore, in the method for preparing a perovskite nanoparticle-polymer composite according to an embodiment of the present invention, perovskite nanoparticles having emission colors of various wavelengths from blue to green can be synthesized by adjusting the temperature of the UV curable resin solution.

3 is a schematic diagram showing a perovskite nanoparticle-polymer composite according to an embodiment of the present invention.

The perovskite nanoparticle-polymer composite 100 according to an embodiment of the present invention is manufactured by the manufacturing method of the perovskite nanoparticle-polymer composite 100 according to an embodiment of the present invention shown in FIG. 1, Since it includes the same components, the same components will be omitted.

The perovskite nanoparticle-polymer composite 100 according to an embodiment of the present invention includes perovskite nanoparticles 110 and a polymer matrix 120 surrounding the perovskite nanoparticles 110, and the polymer matrix 120 is a UV curable polymer.

The perovskite nanoparticles 110 may be dispersed in the polymer matrix 120 .

Therefore, since the perovskite nanoparticles 110 are passivated in the polymer matrix 120, the perovskite nanoparticle-polymer composite 100 according to an embodiment of the present invention improves moisture and long-term stability to the external environment. It can have high stability to the environment.

The UV curable polymer 120 is formed by curing a prepolymer contained in a UV curable resin solution, and the UV curable polymer 120 may include at least one of a (meth)acrylate-based polymer, a urethane-based polymer, an epoxy-based polymer, a vinyl-based polymer, and a silicone-based polymer.

Therefore, the perovskite nanoparticle-polymer composite 100 according to an embodiment of the present invention is synthesized and formed by the LARP method at a low temperature using a UV curable resin solution as an anti-solvent, so that it is composed of only Br anions rather than mixed anions and can exhibit blue light emission. Perovskite nanoparticles 110 whose quantum size is limited to less than the bore radius are passivated by the polymer matrix 120 formed through polymerization of photopolymerizable monomers, resulting in oxygen Alternatively, stability against external chemical species such as moisture may be secured.

The perovskite nanoparticle-polymer composite 100 according to an embodiment of the present invention may be used in an electro-optical device.

For example, the electro-optical device may include a light emitting device, a solar cell, and the like.

[Comparative Example 1]: prepared using toluene as an anti-solvent

To synthesize CsPbBr ₃ nanoparticles, CsBr (0.2 mmol) and PbBr ₂ (0.2 mmol) were dissolved in 5 ml DMF solvent with stirring at 90 °C, and then oleic acid and oleylamine were added and stirred at 90 °C to prepare a precursor solution. When 0.2 ml of the precursor solution was added dropwise to 3 ml of toluene antisolvent and stirred for about 10 minutes, a solution of CsPbBr ₃ nanoparticles exhibiting green light emission was obtained. At this time, the temperature of the toluene anti-solvent was adjusted to 0 ° C, 25 ° C, and 50 ° C, respectively, and the precursor solution was added dropwise to each toluene anti-solvent. After stirring for 10 minutes, the finally obtained CsPbBr ₃ nanoparticle solution exhibited the same green light emission.

Thereafter, the CsPbX3 nanoparticle solution was purified by centrifugation at 5,000 rpm for 10 minutes and then dispersed in 1 ml of hexane to finally prepare a CsPbBr ₃ nanoparticle solution. To prepare blue-emitting perovskite nanoparticles, ZnCl ₂ or MgCl ₂ was added in a molar ratio of (Br:Cl) to a solution of CsPbBr ₃ nanoparticles at a molar ratio of (1:2) and stirred for 30 minutes to perform an anion exchange reaction. Afterwards, a blue-emitting mixed composition was obtained.

[Comparative Example 2]: Prepared by mixing a metal halide-based perovskite nanoparticle solution and a UV curable resin solution

The metal halide-based perovskite nanoparticle solution prepared in [Comparative Example 1] and the UV curable resin solution were mixed in a weight ratio of 1:5, and then stirred to prepare a mixed solution. After coating this solution on a substrate, UV light of 365 nm and 10 mW power was irradiated for 10 minutes to perform photocuring to prepare a perovskite nanoparticle-polymer composite film.

[Example 1]: 0 ℃

A precursor solution was prepared in the same manner as in [Comparative Example 1]. After adjusting the temperature of 3 ml of the UV-curable resin solution to 0°C, 0.2 ml of the precursor solution was added dropwise to prepare a CsPbBr ₃ nanoparticle-UV-curable resin solution exhibiting blue light emission.

[Example 2]: 25 ° C

[Example 2] was prepared in the same manner as [Example 1] except that the temperature of the UV curable resin solution was 25 °C.

[Example 3]: 50 ° C

[Example 3] was prepared in the same manner as [Example 1] except that the temperature of the UV curable resin solution was 50 °C.

4 is an image showing a perovskite nanoparticle-polymer composite film prepared according to Comparative Example 2.

Referring to FIG. 4, it can be seen that the blue light-emitting CsPbBr _x Cl _3-x perovskite quantum dot film prepared by UV curing is not well dispersed in the polymer and exhibits a non-uniform film state.

5 is an image showing a perovskite nanoparticle-polymer composite film prepared according to Example 1 of the present invention.

Referring to FIG. 5 , it can be seen that the blue light-emitting CsPbBr ₃ perovskite quantum dot film prepared by UV curing has a uniform film state and exhibits strong blue light emission on the UV LED.

6 is an image showing a letter-shaped perovskite nanoparticle-polymer composite prepared according to Example 1 of the present invention.

Referring to FIG. 6, the letter-shaped perovskite nanoparticle-polymer composite maintains light emission even when placed in a water tank, and the letter-shaped perovskite nanoparticle-polymer composite prepared according to an embodiment of the present invention has excellent water stability, and the polymer matrix serves as an encapsulation for perovskite nanoparticles (quantum dots).

7 is a graph showing the change in fluorescence according to the synthesis time in the preparation method of the perovskite nanoparticle-polymer composite according to Comparative Example 1.

7, toluene at 0° C. was used as an anti-solvent.

Referring to FIG. 7 , it can be seen that the perovskite nanoparticle-polymer composite according to Comparative Example 1 shows a weak blue color at first, and then the emission wavelength gradually shifts to green as time passes.

8 is a graph showing the fluorescence change according to the synthesis time in the method for preparing the perovskite nanoparticle-polymer composite prepared according to Example 1 of the present invention.

8, a UV curable resin solution at 0° C. was used as an anti-solvent.

Referring to FIG. 8, it can be seen that the blue light emission intensity of the perovskite nanoparticle-polymer composite prepared according to Example 1 of the present invention gradually increases with time.

9 is a graph showing the band gap according to the diameter of perovskite nanoparticles generally reported in the literature.

Referring to FIG. 9 , it can be seen that the bandgap energy of the perovskite nanoparticles decreases as the diameter increases, and the emission color changes from blue to green.

10 is a perovskite nanoparticle according to the temperature of a UV curable resin solution in the preparation method of the perovskite nanoparticle-polymer composite prepared according to Comparative Example 1 (d) and Examples 1 (a) to 3 (c) of the present invention. It is an image showing transmission electron microscopy (TEM) results of nanoparticles.

In Comparative Example 1, toluene at 25° C. was used as an anti-solvent.

Referring to FIG. 10, in the method for producing the perovskite nanoparticle-polymer composite prepared according to Examples 1 to 3 of the present invention, the size of the synthesized perovskite nanoparticles varies according to the temperature of the UV curable resin solution, and when the UV curable resin solution at 0 ° C. (Example 1) is used, it can be seen that it has an amorphous shape with a diameter of about 4 nm.

11 is a graph showing the luminescence intensity according to the temperature of the UV curable resin solution in the preparation method of the perovskite nanoparticle-polymer composite prepared according to Comparative Example 1 and Examples 1 to 3 of the present invention.

Referring to FIG. 11, when the perovskite compound precursor solution was added dropwise to a UV curable resin solution at 0 ° C (Example 1), blue light emission was emitted, sky blue light was emitted at 25 ° C (Example 2), and green light was emitted at 50 ° C (Example 3).

On the other hand, it can be seen that Comparative Example 1 using toluene at 25° C. as an anti-solvent exhibits green light emission.

12 is a graph showing the X-ray diffractometer (XRD) results according to the temperature of the UV curable resin solution in the preparation method of the perovskite nanoparticle-polymer composite prepared according to Comparative Example 1 and Examples 1 to 3 of the present invention.

12, in the perovskite nanoparticle-resin mixed solution, it can be seen that the Cs ₄ PbBr ₆ crystalline phase (CsBr: PbBr ₂ = 4: 1, that is, the phase structure lacking PbBr ₂ ) and the CsPbBr ₃ phase (CsBr: PbBr ₂ = 1: 1) showing the luminescent color exist at the same time.

As described above, although the present invention has been described by the limited embodiments and drawings, the present invention is not limited to the above embodiments, and those skilled in the art can make various modifications and variations from these descriptions. Therefore, the scope of the present invention should not be limited to the described embodiments and should not be defined, and should be defined by not only the claims to be described later, but also those equivalent to these claims.

100: perovskite nanoparticle-polymer composite
110: perovskite nanoparticles 111: ligand
120: polymer matrix

Claims (11)

Preparing a perovskite nanoparticle-resin mixed solution by dropwise adding a perovskite precursor solution to a UV curable resin solution;
coating the perovskite nanoparticle-resin mixed solution on a substrate; and
preparing a perovskite nanoparticle-polymer composite film by UV-curing the perovskite nanoparticle-resin mixture solution coated on the substrate;
including,
The UV curable resin solution includes a prepolymer including a monomer and a multifunctional group and a photoinitiator,
Using the UV curable resin solution as an anti-solvent,
In the step of preparing a perovskite nanoparticle-resin mixed solution by adding the perovskite precursor solution dropwise to the UV curable resin solution, the emission color of the perovskite nanoparticles is adjusted according to the temperature of the UV curable resin solution Method for producing a perovskite nanoparticle-polymer composite, characterized in that.
According to claim 1,
The step of preparing a perovskite nanoparticle-resin mixed solution by adding the perovskite precursor solution dropwise to the UV curable resin solution,
A method for producing a perovskite nanoparticle-polymer composite, characterized in that perovskite nanoparticles are synthesized by a ligand-assisted reprecipitation (LARP) method.
According to claim 2,
The perovskite nanoparticles have a structure of at least one of ABX ₃ , A ₂ BX ₄ , ABX ₄ or A _n−1 B _n X3 _n+1 (wherein A is a monovalent cation or divalent cation, B is a divalent metal cation or trivalent metal cation, X is a monovalent anion, and n is an integer between 2 and 6), characterized in that it has a perovskite nanoparticle-polymer composite manufacturing method .
delete According to claim 1,
Method for producing a perovskite nanoparticle-polymer composite, characterized in that the temperature of the UV curable resin solution is 0 ℃ to 50 ℃.
According to claim 1,
The perovskite precursor solution,
A first perovskite precursor containing a monovalent cation, a second perovskite precursor containing a divalent metal cation or a trivalent metal cation, an organic acid and an organic ligand, characterized in that it comprises a perovskite nanoparticle-polymer composite Method for producing.
delete According to claim 1,
The UV curable resin solution comprises 90% to 98% by weight of a monomer, 1% to 5% by weight of a multifunctional group and 1% to 3% by weight of a photoinitiator, based on the total weight of the perovskite nanoparticles Method for producing a polymer composite.
The perovskite nanoparticle-polymer composite prepared according to the method for preparing a perovskite nanoparticle-polymer composite according to any one of claims 1 to 3, 5, 6, and 8,
perovskite nanoparticles; and
A polymer matrix surrounding the perovskite nanoparticles;
The polymer matrix is a perovskite nanoparticle-polymer composite, characterized in that the UV curable polymer.
According to claim 9,
The UV curable polymer is a perovskite nanoparticle-polymer composite, characterized in that it comprises at least one of (meth) acrylate-based polymers, urethane-based polymers, epoxy-based polymers, vinyl-based polymers and silicon-based polymers.
According to claim 9,
The perovskite nanoparticles have a structure of CsPbBr ₃ and exhibit blue light emission, characterized in that the perovskite nanoparticle-polymer composite.