KR102028279B1 - Self-assembled polymer-perovskite light emitting layer, praparation method thereof and light emitting element comprising the same - Google Patents

Abstract

The present invention provides a self-assembled polymer-perovskite light emitting layer comprising a self-assembled polymer to form a pattern, and a perovskite nanocrystal layer disposed inside the pattern of the self-assembled polymer, a method for manufacturing the same, and light emission including the same. The present invention relates to a device, wherein the self-assembled polymer-perovskite light emitting layer according to the present invention can control the light emission wavelength of the light emitting device by binding the perovskite nanocrystals into the self-assembled polymer pattern, and improve quantum luminous efficiency and brightness In addition, the self-assembling polymer may prevent ion migration between the perovskite nanocrystal layers, thereby improving stability. In addition, the perovskite nanocrystal layer may be patterned into a desired shape and nanometer size region by using various patterns formed by the self-assembled polymer.

Description

Self-assembled polymer-perovskite light emitting layer, praparation method approximately and light emitting element comprising the same}

The present invention relates to a light emitting device, and more particularly, to a light emitting layer for a self-assembled polymer-perovskite light emitting device, a manufacturing method thereof and a light emitting device comprising the same.

The current mega trend of the display market is shifting from the existing high-efficiency high-resolution display to the emotional quality display aiming at high color purity and natural color. In this respect, organic light emitting diode-based organic light emitting diode (OLED) devices have made rapid progress, and inorganic quantum dot LEDs with improved color purity have been actively researched and developed as another alternative. However, both organic and inorganic quantum dot emitters have inherent limitations in terms of materials.

Conventional organic light emitters have the advantage of high efficiency, but the color spectrum is poor due to the broad spectrum. Inorganic quantum dot light emitters have been known to have good color purity, but since the light emission is due to the quantum size effect, it is difficult to control the quantum dot size to be uniform toward higher energy, and thus there is a problem of poor color purity. In addition, the two light emitters are expensive. Therefore, there is a need for a new light emitting body that complements and maintains the disadvantages of the organic and inorganic light emitting bodies.

 Metal halide perovskite materials are very popular because of their low manufacturing costs, simple manufacturing and device fabrication processes, and optical and electrical properties made possible through composition control, and their high charge mobility. . In particular, the metal halide perovskite material has high photoluminescence quantum efficiency, high color purity, and simple color control.

The material having a conventional perovskite structure (ABX ₃ ) is an inorganic metal oxide.

Such inorganic metal oxides are generally oxides (metals such as Ti, Sr, Ca, Cs, Ba, Y, Gd, La, Fe, Mn, etc.) having different sizes at A and B sites. Metals, alkaline earth metals, transition metals and lanthanides) cations are located and oxygen anions are located at the X site, and metal cations at the B site are 6-fold coordination edges with oxygen anions at the X site. It is a substance that is bound as a co-octahedron (corner-sharing octahedron). Examples thereof include SrFeO ₃ , LaMnO ₃ , CaFeO _3, and the like.

In contrast, the metal halide perovskite has an organic ammonium (RNH ₃ ) cation, an organic phosphonium (RPH ₃ ) cation or an alkali metal cation at the A site in the ABX ₃ structure, and a halide anion (Cl ⁻ , Since Br ⁻ , I ⁻ ) are positioned to form a perovskite structure, the composition is completely different from that of the inorganic metal oxide perovskite material.

In addition, the properties of the material will also vary according to the difference between these materials. Inorganic metal oxide perovskite typically exhibits superconductivity, ferroelectricity, and colossal magnetoresistance, and thus, research has been conducted in general for sensors, fuel cells, and memory devices. . For example, yttrium barium copper oxide has superconducting or insulating properties depending on oxygen contents.

Metal halide perovskites, on the other hand, are mainly used as light emitters or photosensitive materials because they have high light absorption, high photoluminescence quantum efficiency and high color purity (below half-width of 20 nm) due to the crystal structure itself. do.

If the organic halide perovskite (i.e. organometallic halide perovskite) is one of the metal halide perovskite materials, the organic ammonium has a smaller band gap than the central metal and the halogen crystal structure (BX ₆ octahedral lattice). In the case of containing chromophores (mainly including conjugated structures), since luminescence occurs in organic ammonium, light having high color purity cannot be emitted, and the half width of the luminescence spectrum is wider than 100 nm, making it unsuitable as a light emitting layer. Therefore, such a case is not very suitable for the high color purity illuminant emphasized in this patent. Therefore, it is important to make the organic ammonium contain no chromophore and to emit light in an inorganic lattice composed of a central metal-halogen element in order to make a high color purity emitter. That is, the present patent focuses on the development of a high color purity high efficiency light emitting device in which light emission occurs in the inorganic lattice. For example, Korean Patent Laid-Open Publication No. 10-2001-0015084 (2001.02.26.) Discloses an electroluminescent device using a dye-containing organic-inorganic hybrid material in the form of a thin film instead of particles to use as a light emitting layer This does not occur in the perovskite lattice structure.

However, to date, metal halide perovskite does not exhibit high luminous efficiency in the blue region. For example, the external quantum efficiency of MAPbBr ₃ based green light emitting diodes is reported to be 8.53% [Science 2015, 350, 1222] or higher, but the efficiency of blue light emitting diodes based on Br-Cl mixed anions or Cl anions Still low (External quantum efficiency: 1.7%, emission wavelength peak: 475 nm) [Adv. Opt. Mater. 2017, 5, 1600920]. Therefore, a method for improving the luminous efficiency of the blue light emitting metal halide perovskite material should be studied.

The luminous efficiency of the metal halide perovskite material can be improved by spatially constraining an exciton or a charge carrier. That is, luminous efficiency may be improved by reducing grain size, introducing a two-dimensional layered structure, or synthesizing perovskite colloidal nanoparticles in the perovskite polycrystalline thin film. Among them, the method of synthesizing colloidal nanoparticles (Colloidal nanoparticles) as the crystal size is smaller than two times the exciton bohr radius (quantum size effect) occurs to control the emission wavelength However, the charge transport is inhibited by the ligand surrounding the perovskite colloidal nanocrystals, and due to the low concentration of the perovskite colloidal nanocrystal solution, it is difficult to form a uniform thin film.

Furthermore, in metal halide perovskite light emitting diodes, ion migration occurs as voltage is applied, resulting in defects, and electrochemical degradation due to charges accumulated at the interface. There is a problem that greatly lowers the luminous efficiency of the lobe-sky light emitting diode.

Therefore, there is a need for a new method to improve the luminous efficiency while controlling the emission wavelength of the metal halide perovskite light emitting layer or light emitting diode, and the metal halide perovskite is suppressed by suppressing ion migration in the metal halide perovskite. There is a need for the development of measures to improve the stability of the system.

On the other hand, in order to use the metal halide perovskite light emitting layer in a large area display or lighting, it is necessary to develop a patterning technology of the light emitting layer. However, until now, the technology for adjusting and patterning the metal halide perovskite emitting layer to a desired shape has not been studied much.

Recently, a patterning process using crinkling of the perovskite-polymer thin film has been reported [Soft Matter, 2017, 13, 1654], but the creasing method has a limitation in that the pattern cannot be adjusted as desired. In addition, spin-on-patterning method using a self-assembled monolayer [Adv. Mater. 2017, 29, 1702902] has been reported, but the method using a self-assembled monolayer can not produce a pattern having a quantum confinement effect, and its utilization is limited in that it requires a complicated photolithography process Can be. Thus, there is a need for the development of new processes that can pattern metal halide perovskite thin films.

1. Republic of Korea Patent Publication No. 10-2001-0015084 (2001.02.26.)

Science 2015, 350, 1222 2. Adv. Opt. Mater. 2017, 5, 1600920 3.Soft Matter, 2017, 13, 1654 4. Adv. Mater. 2017, 29, 1702902

It is a first object of the present invention to provide a self-assembled polymer-perovskite light emitting layer.

It is a second object of the present invention to provide a method for producing the self-assembled polymer-perovskite emitting layer.

A third object of the present invention is to provide a method for patterning a perovskite thin film using the self-assembled polymer.

A fourth object of the present invention is to provide a light emitting device including the self-assembled polymer-perovskite light emitting layer.

In order to achieve the first object, the present invention is formed on a light emitting layer coating member, a self-assembled polymer to form a pattern; And it provides a self-assembled polymer-perovskite light emitting layer comprising a perovskite nanocrystal layer disposed inside the pattern of the self-assembled polymer.

More preferably, the self-assembled polymer may be polyethylene oxide (PEO), polystyrene (PS), polycaprolactone (PCL), polyacrylonitrile (PAN), poly (methyl methacrylate) (PMMA), polyimide (Polyimide), or PVDF (Poly (DF)). random copolymer consisting of two or more polymers selected from the group consisting of vinylidene fluoride), PVK (Poly (n-vinylcarbazole)), PVC (Polyvinylchloride), PDMS (Poly dimethylsiloxane) and their respective derivatives, It may be an alternating copolymer, a block copolymer or a graft copolymer.

More preferably, the pattern of the self-assembled polymer is air of two or more kinds of polymers expressed in a cubic sphere, cylinder, gyroid, lamella, or a combination thereof. It can be formed by removing a polymer of a specific composition from the coalescence.

More preferably, the width of the self-assembled polymer pattern may be 5 ~ 100 nm.

More preferably, the perovskite nanocrystals comprise a structure of ABX ₃ or A ' ₂ A _{n -1} BX _{3n + 1} (n is an integer from 1 to 100), wherein A and A' are each organic Ammonium ions, organic phosphonium ions or alkali metal ions, B is a transition metal, a rare earth metal, an alkaline earth metal, an organic substance, an inorganic substance, ammonium or a combination thereof, X is a halogen ion or a combination of different halogen ions, The ion radius of A 'is greater than the ion radius of A,

The organoammonium is an amidinium group organic ion or an organic ammonium cation, and the amidinium-based organic ion is formamidinium (CH (NH ₂ ) ₂ ) ion, acetamidinium, ( CH ₃ ) C (NH ₂ ) ₂ ) ion, guamidinium (C (NH ₂ ) ₃ ) ion, (C _n H _{2n + 1} ) (C (NH ₂ ) ₂ ) or (C _n F _{2n + 1} ) (C (NH ₂ ) ₂ ) and combinations or derivatives thereof, wherein the organic ammonium cation is CH ₃ NH ₃ , (C _n H _{2n + 1} ) _x NH _{4 -x} , ((C _n H _{2n + 1} ) _y NH _{3 -y} ) (CH ₂ ) _m NH ₃ , (C _n F _{2n + 1} ) _x NH _4-x , ((C _n F _{2n + 1} ) _y NH _{3 -y} ) (CH ₂ ) _m NH ₃ , and combinations or derivatives thereof, n and m may each be an integer of 1 to 100, x may be an integer of 1 to 3, and y may be 1 or 2.

More preferably, the size of the perovskite nanocrystals may be 1 to 990 nm.

More preferably, the light emitting layer may further include an organic layer surrounding the self-assembled polymer between the patterned self-assembled polymer and the perovskite nanocrystal layer.

More preferably, the organic material used in the organic material layer is polyethylene oxide (PEO), polystyrene (PS), polycaprolactone (PCL), polyacrylonitrile (PAN), poly (methyl methacrylate) (PMMA), polydivinylbenzene (PDVB), polyimide ( Polyimide), polythiophene, polyaniline, polypyrrole, poly (3,4-ethylenedioxythiophene), polyvinyllidene fluoride (PVDF), poly (n-vinylcarbazole) (PVK), polyvinylchloride (PVC) and derivatives thereof It may be any one selected from the group consisting of, or a mixture of two or more thereof.

More preferably, the thickness of the organic material layer may be 1 ~ 20 nm.

In addition, in order to achieve the second object, the present invention

Forming a self-assembled polymer pattern on the light emitting layer coating member (S100);

Forming a light emitting layer by forming a perovskite nanocrystal layer in the prepared self-assembled polymer pattern (S200); And

Heat-treating the light emitting layer (S300)

It provides a method for producing the self-assembled polymer-perovskite emitting layer.

More preferably, after forming the self-assembled polymer pattern in the step S100, it may be further performed to form an organic material layer on the patterned self-assembled polymer (S150).

More preferably, the method of forming the perovskite nanocrystal layer is

Preparing a perovskite solution; And

The perovskite solution may be formed by applying and coating the perovskite solution into a self-assembled polymer pattern using a solution process to form a perovskite nanocrystal layer.

More preferably, the perovskite solution may be a first solution in which perovskite is dissolved or a second solution in which perovskite nanocrystalline particles are dispersed.

More preferably, the first solution is a mixture of one or more of AX and A'X and BX ₂ (wherein A, A ', B and X are as defined in claim 5) in an aprotic solvent Can be formed.

More preferably, the second solution can be prepared using a recrystallization method or a hot-injection method.

More preferably, when the perovskite nanocrystal layer is formed on the polymer pattern outside the pattern height of the self-assembled polymer, removing the perovskite nanocrystal layer formed on the polymer pattern (S250). ) Can be performed further.

More preferably, the step of removing the perovskite nanocrystal layer, using only a solvent for dissolving the perovskite nanocrystals dissolved only the perovskite nanocrystal layer located on the self-assembled polymer pattern spin and then spin By removing with a coating.

Furthermore, in order to achieve the third object, the present invention

Forming a self-assembled polymer pattern on the member (S100);

Preparing a perovskite nanopattern by forming a perovskite nanocrystal layer in the prepared self-assembled polymer pattern (S200); And

Heat-treating the perovskite nanopattern (S300)

Provided is a method of patterning a perovskite thin film.

Also preferably, after the perovskite nanopattern is formed in step S200 may further comprise the step of removing the self-assembled polymer.

In addition, in order to achieve the fourth object, the present invention comprises a light-emitting diode, a light-emitting transistor, a laser comprising the self-assembled polymer-perovskite light emitting layer And a light emitting element selected from the group consisting of polarized light emitting elements.

The self-assembled polymer-perovskite light emitting layer according to the present invention can shift the emission wavelength of the light emitting device toward high energy by binding the perovskite nanocrystals into the self-assembled polymer pattern, and improves the quantum luminous efficiency and brightness. In addition, the self-assembling polymer may prevent ion migration between the perovskite nanocrystal layers, thereby improving stability. In addition, the perovskite nanocrystal layer may be patterned into a desired shape and nanometer size region by using various patterns formed by the self-assembled polymer.

1 is a schematic diagram of a self-assembled polymer-perovskite light emitting layer according to an embodiment of the present invention.
Figure 2 is a schematic diagram showing the crystal structure of the perovskite nanocrystals contained in the self-assembled polymer-perovskite light emitting layer according to an embodiment of the present invention.
3 is a schematic diagram of a self-assembled polymer-perovskite light emitting layer according to another embodiment of the present invention.
4 is a flowchart illustrating a method of manufacturing a self-assembled polymer-perovskite light emitting layer according to an embodiment of the present invention.
5 is a schematic diagram showing a process of forming a self-assembled polymer pattern on a substrate according to an embodiment of the present invention.
6 is a flowchart illustrating a method of manufacturing a self-assembled polymer-perovskite light emitting layer according to another embodiment of the present invention.
7 is a schematic diagram illustrating a process of forming an organic material layer on a self-assembled polymer pattern formed on a substrate according to an embodiment of the present invention.
8 is a schematic diagram illustrating a process of forming a perovskite nanocrystal layer in a self-assembled polymer pattern formed on a substrate according to an embodiment of the present invention.
9 is a schematic diagram illustrating a process of forming a perovskite nanocrystal layer in a self-assembled polymer pattern formed on a substrate according to another embodiment of the present invention.
10 is a flowchart illustrating a method of manufacturing a self-assembled polymer-perovskite light emitting layer according to another embodiment of the present invention.
11 is a schematic diagram showing a light emitting device (regular structure) including a self-assembled polymer-perovskite light emitting layer according to an embodiment of the present invention.
12 is a schematic diagram showing a light emitting device (regular structure) including a self-assembled polymer-perovskite light emitting layer according to another embodiment of the present invention.
FIG. 13 is a schematic view showing a light emitting device (inverse structure) including a self-assembled polymer-perovskite light emitting layer according to another embodiment of the present invention.
14 is an electron scanning microscope (SEM) photograph showing the surface of the PS-b-PMMA self-assembled polymer thin film formed on a silicon wafer substrate according to an embodiment of the present invention.
15 is an electron scanning microscope (SEM) photograph showing the surface of the PS-b-PMMA self-assembled polymer thin film formed on the ITO / ZnO substrate according to another embodiment of the present invention.
16 is a schematic diagram showing a perovskite thin film formed without a self-assembled polymer pattern on a substrate according to a comparative example of the present invention.
17 is a graph showing the photoluminescence characteristics of the perovskite nanocrystals with or without the self-assembled polymer pattern according to an experimental example of the present invention.
18 is a view showing a structure that the self-assembled polymer used in the present invention may have a composition.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

While the invention allows for various modifications and variations, specific embodiments thereof are illustrated by way of example in the drawings and will be described in detail below. However, it is not intended to be exhaustive or to limit the invention to the precise forms disclosed, but rather the invention includes all modifications, equivalents, and alternatives consistent with the spirit of the invention as defined by the claims.

When an element such as a layer, region or substrate is referred to as being on another component "on", it will be understood that it may be directly on another element or there may be an intermediate element in between. .

Although the terms first, second, etc. may be used to describe various elements, components, regions, layers, and / or regions, such elements, components, regions, layers, and / or regions It will be understood that it should not be limited by these terms.

In the present specification, the "perovskite nanocrystal layer" is composed of nanocrystalline particles formed by applying a solution in which nanocrystals or perovskite nanocrystal particles formed by applying a perovskite precursor solution are dispersed.

In the present specification, "perovskite nanocrystals" is a material formed by crystallization when the perovskite precursor solution is coated, the nanocrystals include nanocrystalline particles, when referring to the nanocrystalline particles alone " Nanocrystalline particles ".

In the present specification, "perovskite nanocrystalline particles" refers to particles having a ligand bound to a core surface composed of perovskite nanocrystals, which are dispersed in a solvent.

In the present specification, the "light emitting device" may include all devices in which light emission occurs, such as a light emitting diode, a light-emitting transistor, a laser, and a polarized light emitting device.

Self-Assembly Polymers Perovskite Light emitting layer

The present invention provides a self-assembled polymer-perovskite light emitting layer.

1 is a schematic diagram of a self-assembled polymer-perovskite light emitting layer according to an embodiment of the present invention.

Referring to FIG. 1, the self-assembled polymer-perovskite emitting layer 40 according to the present invention may be formed on the light emitting layer applying member 10, and the self-assembled polymer 11 forming a pattern. The perovskite nanocrystal layer 12 formed in the pattern of the self-assembled polymer 11 is included.

In the self-assembling polymer-perovskite emitting layer according to the present invention, the self-assembling polymer 11 is composed of two or more polymers, and the two or more polymers are of a specific type covalently linked through one end of a chain. As a polymer, periodic structures in the form of cubic spheres, cylinders, gyroids, lamellas, or combinations thereof at the nanoscale level spontaneously by molecules in the polymer Can be expressed. Periodic patterns can be formed by removing specific polymers from self-assembled polymers expressed in the form of cubic spheres, cylinders, gyroids, lamellas, or combinations thereof. The patterns may improve luminous efficiency of the perovskite material by binding the perovskite nanocrystals, and may block ion migration between the perovskite crystals, thereby improving stability. The light emission wavelength of the light emitting diode can be shifted toward high energy, and the quantum light emitting efficiency and luminance can be improved.

In general, in the case of the perovskite without the quantum confinement effect, since the exciton binding energy is as low as several tens of meV, the excitons are easily separated at room temperature, thereby reducing the luminous efficiency. . However, if the quantum binding effect is generated by spatially confining the perovskite crystal in the self-assembled polymer pattern, the exciton binding energy is increased, and thus the exciton is hardly separated even at room temperature, so that the perovskite emitting layer Photoluminescence efficiency and electroluminescence efficiency and brightness of the perovskite light emitting diode can be improved.

Such self-assembled polymers 11 include polyethylene oxide (PEO), polystyrene (PS), polycaprolactone (PCL), polyacrylonitrile (PAN), poly (methyl methacrylate) (PMMA), poly dimethylsiloxane (PDMS), polyimide (Polyimide), Random copolymer, alternating, consisting of two or more polymers selected from the group consisting of polyvinyllidene fluoride (PVDF), poly (n-vinylcarbazole) (PVK), polyvinylchloride (PVC), and derivatives thereof An alternating copolymer, a block copolymer, or a graft copolymer may be used, but is not limited thereto.

The self-assembled polymer may be composed of a single layer or a multilayer of two or more layers depending on the thickness of the light emitting layer to be formed.

In the self-assembled polymer-perovskite emitting layer according to the present invention, the pattern of the self-assembled polymer 11 is as described above, cubic sphere (cybic), cylinder (cylinder), gyroid (gyroid), lamellae It may be formed by removing a polymer of a specific composition from a copolymer of two or more polymers expressed in a structure of a lamellar or a combination thereof.

At this time, the width of the formed self-assembled polymer pattern is preferably 5 ~ 100 nm, more preferably 5 ~ 30 nm. If the width of the polymer pattern is less than 5 nm, there is a problem in that no phase is formed due to a thermodynamic limit. If the width of the polymer pattern is more than 100 nm, there is a problem in that the mobility of the block copolymer is poor and the phase is not formed.

In the self-assembled polymer-perovskite light emitting layer according to the present invention, the perovskite nanocrystals constituting the perovskite nanocrystal layer 12 are light emitters forming the light emitting layer, which can be dispersed in an organic solvent. Nanocrystalline or colloidal nanoparticles of organic-inorganic hybrid perovskite or metal halide perovskite.

The perovskite nanocrystals comprise a structure of ABX ₃ or A ′ ₂ A _n-1 BX _{3n + 1} (n is an integer of 1 to 100), wherein A and A ′ are organoammonium ions, organic Phosphonium ions or alkali metal ions, B is a transition metal, a rare earth metal, an alkaline earth metal, an organic substance, an inorganic substance, ammonium or a combination thereof, and X may be a halogen ion or a combination of different halogen ions. At this time, the ion radius of the A 'is larger than the ion radius of the A. In this case, when B is an organic material, it may be the same as A or A ', and other organic ammonium ions, organic phosphonium ions, alkali metal ions, or other organic materials.

More specifically, the perovskite nanocrystals may be a metal halide perovskite, and the crystal structure of the metal halide perovskite is shown in FIG. 2 with the central metal (B) in the center. , 6 halogen elements (X) are located on all surfaces of the cube with face centered cubic (FCC), and A or A '(organic ammonium, organic phosphonium or Alkali metal) forms a structure where eight are located at all vertices of the cube. At this time, all sides of the cube form 90 °, and include a cubic structure having the same horizontal length, vertical length, and height, as well as tetragonal structures having the same horizontal length and vertical length but different height lengths.

The organoammonium is an amidinium group organic ion or an organic ammonium cation, and the amidinium-based organic ion is formamidinium (CH (NH ₂ ) ₂ ) ion, acetamidinium, ( CH ₃ ) C (NH ₂ ) ₂ ) ion, guamidinium (C (NH ₂ ) ₃ ) ion, (C _n H _{2n + 1} ) (C (NH ₂ ) ₂ ) or (C _n F _{2n + 1} ) (C (NH ₂ ) ₂ ) and combinations or derivatives thereof, wherein the organic ammonium cation is CH ₃ NH ₃ , (C _n H _{2n + 1} ) _x NH _{4 -x} , ((C _n H _{2n + 1} ) _y NH _{3 -y} ) (CH ₂ ) _m NH ₃ , (C _n F _{2n + 1} ) _x NH _4-x , ((C _n F _{2n + 1} ) _y NH _3-y ) (CH ₂ ) _m NH ₃ , and combinations or derivatives thereof (n and m are each an integer of 1 to 100, x is an integer of 1 to 3, and y is 1 or 2).

The transition metal may be Ge, Sn or Pb, the rare earth metal may be Eu or Yb, and the alkaline earth metal may be Ca or Sr. In addition, X may be Cl, Br, I or a combination thereof.

The perovskite nanocrystals may be dissolved or dispersed in an organic solvent, and the organic solvent may be a protic solvent or an aprotic solvent.

For example, the protic solvent may be selected from methanol, ethanol, isopropyl alcohol, tert-butanol and formic acid, and the aprotic solvent is dimethylformamide, dimethyl sulfoxide, xylene, toluene, hexane , Cyclohexene, gamma butyrolactone, N-methylpyrrolidone and dichloroethylene, trichloroethylene, chloroform, chlorobenzene and dichlorobenzene.

In addition, the perovskite nanocrystals may be in the form of a spherical, cylindrical, elliptical cylinder or polygonal cylinder.

In addition, the band gap energy of the perovskite nanocrystals may be 1 eV to 5 eV.

In addition, the emission wavelength of the perovskite nanocrystals may be 200nm to 1300nm.

In addition, the size of the perovskite nanocrystals may be 1 to 990 nm. If the size of the perovskite nanocrystals exceeds 990 nm, there may be a fundamental problem that excitons do not go into luminescence but are separated into free charges and disappear due to thermal ionization and delocalization of charge carriers in large nanocrystals.

On the other hand, the perovskite nanocrystals may further include a plurality of organic ligands (not shown) surrounding the surface.

The organic ligands may include alkyl halides or organic acids.

The alkyl halide may be a structure of alkyl-X. In this case, the halogen element corresponding to X may include Cl, Br, or I. In this case, the alkyl structure includes primary alcohols and secondary alcohols having a structure such as acyclic alkyl having a structure of C _n H _{2n +1} , C _n H _{2n + 1} OH, and the like. Tertiary alcohol, alkylamine with alkyl-N structure (ex. Hexadecyl amine, 9-Octadecenylamine 1-Amino-9-octadecene (C ₁₉ H ₃₇ N)), p-substituted aniline (p-substituted aniline), phenyl ammonium or fluorine ammonium, but is not limited thereto.

The organic acid may be 4,4'-azobis (4-cyanopaleric acid) (4,4'-Azobis (4-cyanovaleric acid)), acetic acid (Acetic acid), 5-minosalicyclic acid ( 5-Aminosalicylic acid, Acrylic acid, L-Aspentic acid, 6-Brohexahexanoic acid, 6-Bromohexanoic acid, Promoacetic acid, Dichloro Dichloro acetic acid, Ethylenediaminetetraacetic acid, Isobutyric acid, Itaconic acid, Maleic acid, Maleic acid, r-maleimidobutyl R-Maleimidobutyric acid, L-Malic acid, 4-nitrobenzoic acid, 1-pyrenecarboxylic acid or oleic It may include an acid (oleic acid).

On the other hand, the light emitting layer according to the present invention, as shown in Figure 3, the organic material layer 13 surrounding the self-assembled polymer 11 between the patterned self-assembled polymer 11 and the perovskite nanocrystalline layer 12 ) May be further included.

When the width of the pattern of the self-assembled polymer 11 is too wide, the organic layer 13 may be coated on the self-assembled polymer 11 to reduce the width.

The organic layer 13 may use a polymer having the same composition as the self-assembled polymer, or may use another polymer. For example, the organic material used in the organic material layer is polyethylene oxide (PEO), polystyrene (PS), polycaprolactone (PCL), polyacrylonitrile (PAN), poly (methyl methacrylate) (PMMA), polydivinylbenzene (PDVB), and polyimide (Polyimide). , Polythiophene, polyaniline, polypyrrole, poly (3,4-ethylenedioxythiophene), polyvinyllidene fluoride (PVDF), poly (n-vinylcarbazole) (PVK), polyvinylchloride (PVC) and derivatives thereof It may be any one selected from the group, or a mixture of two or more, but is not limited thereto.

The organic layer 13 may be formed on the self-assembled polymer pattern by a deposition method used in the art. For example, the chemical vapor deposition method (chemical vapor deposition, CVD) or thermal deposition method (thermal deposition) Can be used, but is not limited thereto.

The thickness of the organic material layer 13 may be adjusted according to the width of the formed self-assembled polymer pattern, for example, may be 1 ~ 20 nm, but is not limited thereto.

Self-Assembly Polymers Perovskite Emitting layer  Manufacturing method

4 is a flowchart illustrating a method of manufacturing a self-assembled polymer-perovskite light emitting layer according to an embodiment of the present invention.

4, the method of manufacturing a self-assembled polymer-perovskite light emitting layer of the present invention

Forming a self-assembled polymer pattern on the light emitting layer coating member (S100);

Forming a light emitting layer by forming a perovskite nanocrystal layer in the prepared self-assembled polymer pattern (S200); And

And heat-treating the light emitting layer (S300).

Hereinafter, the present invention will be described step by step.

First, step S100 is a step of forming a self-assembled polymer pattern on the light emitting layer coating member.

In this step, first, a light emitting layer coating member is prepared.

The light emitting layer coating member may be a substrate, an electrode, or a semiconductor layer. The substrate, the electrode, or the semiconductor layer may be a substrate, an electrode, or a semiconductor layer that can be used in the light emitting device. In addition, the light emitting layer coating member may have a form in which substrates / electrodes are sequentially stacked or a form in which substrates / electrodes / semiconductor layers are sequentially stacked.

For the description of the substrate, the electrode, or the semiconductor layer, reference will be made to the contents of the light emitting device including the self-assembled polymer-perovskite emitting layer described below.

Next, a self-assembled polymer pattern is formed on the light emitting layer coating member.

In the self-assembled polymer used in the present invention, since two or more kinds of polymers are formed in a cylinder shape on the light emitting layer coating member through a self-assembly reaction, a pattern may be formed by removing one of the polymers formed in the cylinder shape.

As an example, as shown in FIG. 5, a PS-b-PMMA block having a random copolymer thin film 11a formed on a substrate 10 and having a cylindrical shape on the random copolymer thin film 11a is formed. After the copolymer thin film 11b is formed, the block copolymer in the form of cylinder obtained through self-assembly may be selectively etched to the PMMA cylinder portion and the random copolymer thin film under the PMMA to form a self-assembled polymer pattern in which only the PS portion remains. Can be.

In addition, as shown in FIG. 6, after the self-assembled polymer pattern is formed, a step (S150) of forming the organic material layer 13 on the patterned self-assembled polymer 11 may be further performed.

The organic layer 13 may be coated on the self-assembled polymer 11 when the width of the pattern of the self-assembled polymer 11 is too wide, as shown in FIG. 7 to reduce the width.

The organic layer 13 may use a polymer having the same composition as the self-assembled polymer, or may use another polymer. For example, the organic material used in the organic material layer is polyethylene oxide (PEO), polystyrene (PS), polycaprolactone (PCL), polyacrylonitrile (PAN), poly (methyl methacrylate) (PMMA), polydivinylbenzene (PDVB), and polyimide (Polyimide). , Polythiophene, polyaniline, polypyrrole, poly (3,4-ethylenedioxythiophene), polyvinyllidene fluoride (PVDF), poly (n-vinylcarbazole) (PVK), polyvinylchloride (PVC) and derivatives thereof It may be any one selected from the group, or a mixture of two or more, but is not limited thereto.

The organic layer 13 may be formed on the self-assembled polymer pattern by a deposition method used in the art. For example, the chemical vapor deposition method (chemical vapor deposition, CVD) or thermal deposition method (thermal deposition) Can be used, but is not limited thereto.

The thickness of the organic material layer 13 may be adjusted according to the width of the formed self-assembled polymer pattern, for example, may be 1 ~ 20 nm, but is not limited thereto.

Next, step S200 is a step of forming a light emitting layer by forming a perovskite nanocrystal layer in the prepared self-assembled polymer pattern.

The method for forming the perovskite nanocrystalline layer

Preparing a perovskite solution; And

Forming a perovskite nanocrystal layer by applying and coating the perovskite solution into a self-assembled polymer pattern using a solution process.

First, the perovskite solution is prepared.

The perovskite solution may be a first solution in which perovskite is dissolved or a second solution in which perovskite nanocrystalline particles are dispersed.

The first solution may be formed by dissolving AX and BX ₂ in a proportion in an aprotic solvent. For example, by dissolving AX and BX ₂ in a 1: 1 ratio in an aprotic solvent, ABX ₃ A first solution in which perovskite is dissolved can be prepared.

In addition, the first solution may be formed by mixing at least one of AX and A'X and BX ₂ in an aprotic solvent.

At this time, the aprotic solvent is dimethylformamide, dimethyl sulfoxide, xylene, toluene, hexane, cyclohexene, gamma butyrolactone, N-methylpyrrolidone and dichloroethylene, trichloro It may be selected from ethylene, chloroform, chlorobenzene and dichlorobenzene, but is not limited thereto.

In addition, the perovskite includes an organic-inorganic hybrid perovskite or metal halide perovskite, and may be a material having a two-dimensional crystal structure. For example, the perovskite nanocrystals comprise a structure of ABX ₃ or A ′ ₂ A _n-1 BX _{3n + 1} (n is an integer from 1 to 100), wherein A and A ′ are organoammonium, respectively. Ions, organic phosphonium ions or alkali metal ions, wherein B is a transition metal, a rare earth metal, an alkaline earth metal, an organic substance, an inorganic substance, ammonium or a combination thereof, and X is a halogen ion or a combination of different halogen ions. At this time, the ion radius of the A 'is larger than the ion radius of the A.

The second solution may be prepared using a recrystallization method or a hot-injection method.

The recrystallization method

Preparing a first a solution in which perovskite is dissolved in an aprotic solvent and a first b solution in which an alkyl halide or organic acid surfactant is dissolved in a protic or aprotic solvent. ; And

Dropping the first solution on the first solution to prepare a second solution in which the perovskite nanocrystalline particles are dispersed.

In this case, the preparation of the first a solution in which the aprotic solvent and the perovskite are dissolved is the same as the preparation of the first solution.

In this case, when preparing the 1b solution, the protic solvent may be selected from methanol, ethanol, isopropyl alcohol, tert-butanol and formic acid, and the aprotic solvent may be dimethylformamide, dimethyl sulfoxide, or xylene. , Toluene, hexane, cyclohexene, gamma butyrolactone, N-methylpyrrolidone and dichloroethylene, trichloroethylene, chloroform, chlorobenzene and dichlorobenzene, but are not limited thereto.

In addition, the alkyl halide surfactant may be of the structure of alkyl-X. In this case, the halogen element corresponding to X may include Cl, Br, or I. In addition, where an alkyl structure, the primary alcohol (primary alcohol) having a structure such as acyclic alkyl _{(acyclic alkyl), C n H} 2n + 1 OH having the structure C _n H _{2n + 1,} the secondary alcohol (secondary alcohol) Tertiary alcohol, alkylamine with alkyl-N structure (ex. Hexadecyl amine, 9-Octadecenylamine 1-Amino-9-octadecene (C ₁₉ H ₃₇ N)), p-substituted aniline (p-substituted aniline) and phenyl ammonium and fluorine ammonium, but are not limited thereto.

On the other hand, organic acid surfactants may be used instead of alkyl halide surfactants.

For example, the organic acid surfactant may be 4,4'-Azobis (4-cyanovaleric acid) (4,4'-Azobis (4-cyanovaleric acid)), acetic acid, 5- 5-Aminosalicylic acid, Acrylic acid, L-Aspentic acid, 6-Bromohexanoic acid, Promoacetic acid ( Bromoacetic acid, Dichloro acetic acid, Ethylenediaminetetraacetic acid, Isobutyric acid, Itaconic acid, Maleic acid , r-Maleimidobutyric acid (r-Maleimidobutyric acid), L-Malic acid (L-Malic acid), 4-nitrobenzoic acid (4-Nitrobenzoic acid), 1-pyrene carboxylic acid (1- Pyrenecarboxylic acid or oleic acid, but is not limited thereto.

Next, when the 1a solution is dropped into the 1b solution and mixed, the organic-inorganic perovskite (OIP) is precipitated in the 1b solution due to the difference in solubility. At this time, the first b solution may be stirred. For example, nanoparticles may be synthesized by slowly adding dropwise drops of the first a solution in which an organic-inorganic perovskite (OIP) is dissolved to the first b solution in which the strongly stirred alkyl halide surfactant is dissolved.

In addition, the organic-inorganic perovskite (OIP) precipitated in the solution of solution 1b generates an organic-inorganic perovskite nanocrystals (OIP-NC) that are well dispersed while the alkyl halide surfactant stabilizes the surface. Accordingly, a second solution including the organic-inorganic perovskite nanocrystal particles including the organic-inorganic perovskite nanocrystals and a plurality of alkyl halide organic ligands surrounding the organic / inorganic perovskite nanocrystals can be prepared.

In addition, the hot-injection method

Adding AX and a surfactant to a non-polar solvent and heating at a high temperature of 100 to 150 ° C. in an inert gas atmosphere to prepare a 1c solution;

Preparing a 1d solution by adding BX ₂ , an amine ligand, and a surfactant to a nonpolar solvent and heating at a high temperature of 100 to 150 ° C. in an inert gas atmosphere;

Injecting the solution 1c into the 1d solution using a syringe (syringe) or a pipette (pipet) in a hot state, and then reacting to prepare a second solution in which the perovskite nanocrystalline particles are dispersed.

Next, a perovskite nanocrystal layer is formed by applying and coating the perovskite solution into a self-assembled polymer pattern using a solution process.

Specifically, as shown in Figure 8, the prepared perovskite solution is coated by coating in a self-assembled polymer pattern that is drilled in the form of a cylinder. The coating method may be a solution process, but is not limited thereto.

The solution process is spin-coating, drop-casting, bar coating, slot-die coating, gravure-printing, nozzle printing. ), Ink-jet printing, screen printing, electrohydrodynamic jet printing, and at least one process selected from the group consisting of electrospray. .

However, if the perovskite nanocrystal layer is formed on the polymer pattern outside the height of the polymer pattern, as shown in Figure 9, as shown in Figure 10, the perovskite formed on the polymer pattern Removing the nanocrystalline layer may be further performed (S250).

The perovskite nanocrystal layer formed on the polymer pattern is removed by dropping a solvent dissolving perovskite on the perovskite nanocrystal layer. After melting, it may be carried out by removing by spin coating or the like.

Next, step S300 is a step of heat treating the manufactured light emitting layer.

The heat treatment may be performed for 1 to 200 minutes at 40 ~ 250 ℃. If the heat treatment temperature is less than 40 ° C., there is a problem that the heat treatment effect is lowered. If the heat treatment temperature is outside 250 ° C., the perovskite or the polymer material may be thermally decomposed.

Through the heat treatment, the solvent is evaporated to strongly bind the perovskite nanocrystals in the pattern of the polymer.

In one embodiment of the present invention by dissolving CsBr and PbBr ₂ in dimethyl sulfoxide (DMSO) to prepare a metal halide perovskite (CsPbBr ₃ ) solution, the metal halide perovskite on a substrate on which a self-assembled polymer pattern is formed Solution was spin-coated and heat-treated at 70 ° C. for 10 minutes to prepare a self-assembled polymer-perovskite light emitting layer.

The self-assembled polymer-perovskite emitting layer prepared by the above method binds the perovskite nanocrystals into the self-assembled polymer pattern, thereby shifting the emission wavelength toward high energy and improving the emission efficiency of the perovskite material. And, the self-assembled polymer located between the perovskite nanocrystalline layer can prevent the ion transfer phenomenon between the perovskite nanocrystalline layer can improve the stability.

Patterning method of perovskite thin film

In the present invention, the self-assembled polymer pattern may be used for nano patterning of the perovskite light emitting layer by having a pattern of a nano region.

Accordingly, the present invention provides a method for patterning a perovskite thin film.

The method of patterning the perovskite thin film

Forming a self-assembled polymer pattern on the member (S100);

Preparing a perovskite nanopattern by forming a perovskite nanocrystal layer in the prepared self-assembled polymer pattern (S200); And

And heat treating the perovskite nanopattern (S300).

The patterning method of the perovskite thin film according to the present invention is applied to the method of manufacturing the self-assembled polymer-perovskite emitting layer described above, the pattern of the self-assembled polymer is as shown in Figure 18, (a) cubic Perovskite nanocrystals can be implemented in various forms such as spear (cubic sphere), (b) cylinder, (c) gyroid, (d) lamella, or a combination thereof. The pattern of the layer can also be embodied in the same form as above.

Therefore, the method of patterning the perovskite thin film may be subjected to the same steps as the above-described method of manufacturing the self-assembled polymer-perovskite light emitting layer. As described above, the same content is omitted.

The manufactured perovskite nanopatterns may be used together with the self-assembled polymer, or may be applied to various device fabrication processes by improving the device performance by selectively removing the self-assembled polymer, thereby removing the insulating properties of the self-assembled polymer.

Accordingly, the method of patterning the perovskite thin film may further include removing the self-assembled polymer after the perovskite nanopattern is formed in S200.

The implemented perovskite nanopattern can be very useful for large area device implementation, and can also be used for purposes such as polarized emission.

Self-Assembly Polymers Perovskite Emitting layer  Light emitting device comprising

The present invention also provides a light emitting device comprising the self-assembled polymer-perovskite light emitting layer.

Here, the light emitting device may include all light emitting devices such as light-emitting diodes, light-emitting transistors, lasers, and polarized light emitting devices.

11 to 13 are cross-sectional views showing light emitting devices according to an embodiment of the present invention.

Referring to FIG. 11, the light emitting device according to the present invention may include an anode 20 and a cathode 70, and a light emitting layer 40 disposed between the two electrodes, and the anode 20 and the light emitting layer 40. ) May be provided with a hole injection layer 23 to facilitate the injection of holes. In addition, an electron transport layer 55 for transporting electrons and an electron injection layer 53 for facilitating injection of electrons may be provided between the light emitting layer 40 and the cathode 70.

In addition, the light emitting device according to the present invention may further include a hole transport layer 25 for transporting holes between the hole injection layer 23 and the light emitting layer 40, as shown in FIG.

In addition, a hole blocking layer (not shown) may be disposed between the light emitting layer 40 and the electron transport layer 55. In addition, an electron blocking layer (not shown) may be disposed between the light emitting layer 40 and the hole transport layer 25. However, the present invention is not limited thereto, and the electron transport layer 55 may serve as the hole blocking layer, or the hole transport layer 25 may serve as the electron blocking layer.

When forward bias is applied to the light emitting device, holes are introduced into the light emitting layer 40 from the anode 20, and electrons are introduced into the light emitting layer 40 from the cathode 70. Electrons and holes introduced into the emission layer 40 combine to form excitons, and light is emitted as the excitons transition to the ground state.

In this case, the light emitting layer 40 may use a self-assembled polymer-perovskite light emitting layer according to the present invention.

The self-assembled polymer-perovskite light emitting layer according to the present invention can shift the emission wavelength of the light emitting device toward high energy by binding the perovskite nanocrystals into the self-assembled polymer pattern, and emit light of the perovskite material. The efficiency can be improved, and the self-assembled polymer can prevent ion migration between the perovskite nanocrystals, thereby improving stability.

The anode 20 may be a conductive metal oxide, a metal, a metal alloy, or a carbon material. Conductive metal oxides are indium tin oxide (ITO), fluorine tin oxide (FTO), antimony tin oxide (ATO), fluorine-doped tin oxide (FTO), SnO ₂ , ZnO Or combinations thereof. Suitable metals or metal alloys as the anode 20 may be Au and CuI. The carbon material may be graphite, graphene, or carbon nanotubes.

The hole injection layer 23 and / or the hole transport layer 25 are layers having a HOMO level between the work function level of the anode 20 and the HOMO level of the light emitting layer 40, from the anode 20 to the light emitting layer 40. To increase the efficiency of hole injection or transport.

The hole injection layer 23 or the hole transport layer 25 may include a material commonly used as a hole transport material, and one layer may include different hole transport material layers. Hole transporters are, for example, mCP (N, Ndicarbazolyl-3,5-benzene); PEDOT: PSS (poly (3,4-ethylenedioxythiophene): polystyrenesulfonate); NPD (N, N′-di (1-naphthyl) -N, N′-diphenylbenzidine); N, N'-diphenyl-N, N'-di (3-methylphenyl) -4,4'-diaminobiphenyl (TPD); DNTPD (N ⁴ , N ^{4 ′} -Bis [4- [bis (3-methylphenyl) amino] phenyl] -N ⁴ , N ^{4 ′} -diphenyl- [1,1′-biphenyl] -4,4′-diamine) ; N, N'-diphenyl-N, N'- dinaphthyl-4,4'-diaminobiphenyl; N, N, N'N'-tetra-p-tolyl-4,4'-diaminobiphenyl; N, N, N'N'-tetraphenyl-4,4'-diaminobiphenyl; Porphyrin compound derivatives such as copper (II) 1,10,15,20-tetraphenyl-21H, 23H-porphyrin and the like; TAPC (1,1-Bis [4- [N, N'-Di (p-tolyl) Amino] Phenyl] Cyclohexane); Triarylamine derivatives such as N, N, N-tri (p-tolyl) amine, 4,4 ', 4'-tris [N- (3-methylphenyl) -N-phenylamino] triphenylamine; Carbazole derivatives such as N-phenylcarbazole and polyvinylcarbazole; Phthalocyanine derivatives such as metal phthalocyanine and copper phthalocyanine; Starburst amine derivatives; Enamine stilbene derivatives; Derivatives of aromatic tertiary amines and styryl amine compounds; And polysilanes and the like. The hole transport material may serve as an electron blocking layer.

The hole blocking layer serves to prevent diffusion of triplet excitons or holes in the direction of the cathode 70 and may be arbitrarily selected from known hole blocking materials. For example, an oxadiazole derivative, a triazole derivative, a phenanthroline derivative, TSPO1 (diphenylphosphine oxide-4- (triphenylsilyl) phenyl), etc. can be used.

The electron injection layer 53 and / or the electron transport layer 55 are layers having an LUMO level between the work function level of the cathode 70 and the LUMO level of the light emitting layer 40, from the cathode 70 to the light emitting layer 40. It functions to increase the injection or transport efficiency of electrons.

The electron injection layer 53 may be, for example, LiF, NaCl, CsF, Li ₂ O, BaO, BaF ₂ , or Liq (lithium quinolate).

Electron transport layer 55 is TSPO1 (diphenylphosphine oxide-4- (triphenylsilyl) phenyl), TPBi (1,3,5-tris (N-phenylbenzimidazol-2-yl) benzene), tris (8-quinolinorate Aluminum (Alq3), 2,5-diaryl silol derivative (PyPySPyPy), perfluorinated compound (PF-6P), COTs (Octasubstituted cyclooctatetraene), TAZ (see formula below), Bphen (4,7-diphenyl) -1,10-phenanthroline (4,7-diphenyl-1,10-phenanthroline), BCP (see formula below), or BAlq (see formula below).

The cathode 70 is a conductive film having a lower work function than the anode 20. For example, a metal such as aluminum, magnesium, calcium, sodium, potassium, indium, yttrium, lithium, silver, lead, cesium, or the like It can be formed using a combination of two or more kinds of.

The anode 20 and the cathode 70 may be formed using a sputtering method, a vapor deposition method, or an ion beam deposition method. The hole injection layer 23, the hole transport layer 25, the light emitting layer 40, the hole blocking layer, the electron transport layer 55, and the electron injection layer 53 irrespective of each other are deposited or coated, for example spraying , Spin coating, dipping, printing, doctor blading, or electrophoresis.

The light emitting device may be disposed on a substrate (not shown). The substrate may be disposed below the anode 20 or may be disposed above the cathode 70. In other words, the anode 20 may be formed before the cathode 70 or the cathode 70 may be formed before the anode 20 on the substrate. Accordingly, the light emitting device can have both the forward structure of FIGS. 11 and 12 and the reverse structure of FIG. 13.

The substrate may be a light transmissive substrate as a flat member, in which case the substrate is glass; Ceramic materials; It may be made of a polymer material such as polycarbonate (PC), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyimide (PI), polypropylene (PP) and the like. However, the present invention is not limited thereto, and the substrate may be a metal substrate capable of light reflection.

Hereinafter, preferred examples are provided to aid the understanding of the present invention. However, the following experimental examples are only for helping understanding of the present invention, and the present invention is not limited to the following experimental examples.

< Production Example  1> within self-assembled polymer pattern Perovskite  Nano crystals are placed Light emitting layer  Produce

Step 1: On a substrate  Self-assembled polymer pattern formation

UV-ozone treatment was performed on a silicon (Si) wafer substrate to form an -OH group on the substrate. Next, a random copolymer was spin-coated on the substrate to form a OH terminated random copolymer thin film having the —OH group attached to the end thereof. Thereafter, the substrate was heat treated at 160 ° C. for one day so that the substrate and the random copolymer were grafted. Thereafter, the random copolymer not bonded to the substrate was removed with a toluene solution.

Next, a block copolymer thin film having a cylindrical shape was formed on the random copolymer thin film. Specifically, a block copolymer (PS-b-PMMA) of polystyrene (PS) and poly (methyl methacrylate) (PMMA) having a cylinder molecular weight was spin-coated to form a PS-b-PMMA thin film, followed by 250 Heat treatment at ° C gave fluidity to the block copolymer to form a self-assembled cylinder phase.

Next, in the block-type copolymer obtained through self-assembly, reactive ion etching (RIE) or acetic acid solution treatment is performed to selectively etch the PMMA cylinder portion and the random copolymer thin film under the PMMA. The remaining self-assembled polymer pattern was obtained.

The result of observing the prepared self-assembled polymer pattern through a scanning electron microscope (SEM) is shown in FIG. 14.

As shown in FIG. 14, it can be seen that a self-assembled polymer pattern having a shape with holes formed in a hexagonal dense structure is formed on the substrate.

Step 2: preparing a metal halide perovskite solution

CsBr 30 mg and PbBr ₂ 47 mg was dissolved in 1 mL of dimethyl sulfoxide (DMSO) to prepare a metal halide perovskite (CsPbBr ₃ ) solution (first solution).

Step 3: preparing a light emitting layer in which the perovskite nanocrystal layer is formed in the self-assembled polymer pattern

Spin-coated the metal halide perovskite solution prepared in step 2 on the substrate on which the self-assembled polymer pattern prepared in step 1 was formed, and heat-treated at 70 ° C. for 10 minutes to form a cylindrical self-assembled polymer pattern. A self-assembled polymer-perovskite light emitting layer having a perovskite nanocrystal layer formed therein was formed.

< Production Example  2>

The metal halide perovskite (CsPbBr ₃ ) solution prepared in Step 2 of Preparation Example 1 was spin-coated on the substrate on which the self-assembled polymer pattern was prepared in Step 1 of Preparation Example 1 The self-assembled polymer-perovskite light emitting layer in which the lobe-sky nanocrystal layer was formed was formed.

Next, DMSO used as a solvent of perovskite was dropped on the metal halide perovskite thin film to melt only the metal halide perovskite layer located on the self-assembled polymer pattern, and DMSO was removed through spin coating. .

Thereafter, heat treatment was performed at 70 ° C. for 10 minutes.

< Production Example  3>

After dropping the metal halide perovskite (CsPbBr ₃ ) solution prepared in Step 2 of Preparation Example 1 on the substrate having the self-assembled polymer pattern prepared in Step 1 of Preparation Example 1, the solvent was spontaneously dried. A self-assembled polymer-perovskite light emitting layer in which perovskite nanocrystals were disposed in a self-assembled polymer pattern was formed.

Next, DMSO used as a solvent of perovskite was dropped on the metal halide perovskite thin film to melt only the metal halide perovskite layer located on the self-assembled polymer pattern, and DMSO was removed through spin coating. .

Thereafter, heat treatment was performed at 70 ° C. for 10 minutes.

< Production Example  4>

A self-assembled polymer pattern was formed on the substrate in the same manner as in Step 1 of Preparation Example 1, except that an ITO / ZnO substrate was used instead of the silicon wafer substrate.

The result of observing the formed self-assembled polymer pattern through a scanning electron microscope (SEM) is shown in Figure 15.

As shown in FIG. 15, it can be seen that a self-assembled polymer pattern having a shape with holes formed in a hexagonal dense structure is formed on a substrate.

Thereafter, the self-assembled polymer-perovskite light emitting layer in which the perovskite nanocrystal layer was formed in the self-assembled polymer pattern was formed in the same manner as in steps 2 and 3 of Preparation Example 1.

< Production Example  5>

A self-assembled polymer-perovskite light emitting layer in which a perovskite nanocrystal layer was formed in a self-assembled polymer pattern was formed in the same manner as in Preparation Example 2, except that an ITO / ZnO substrate was used instead of a silicon wafer substrate. .

< Production Example  6>

A self-assembled polymer-perovskite light emitting layer in which a perovskite nanocrystal layer was formed in a self-assembled polymer pattern was formed in the same manner as in Preparation Example 3, except that an ITO / ZnO substrate was used instead of a silicon wafer substrate. .

<Manufacture example 7>

Step 1: forming a self-assembled polymer pattern on the substrate

The self-assembled polymer pattern was formed on the silicon wafer substrate by the same method as in Step 1 of Preparation.

Step 2: preparing a metal halide perovskite nanocrystalline particle dispersion solution (recrystallization method)

57.9 mg of CH ₃ NH ₃ Br and 253.2 mg of PbBr ₂ were dissolved in 3 mL of dimethylformamide (DMF) to prepare a metal halide perovskite (MAPbBr ₃ ) solution. And the MAPbBr ₃ solution was mixed with 23 μL of hexylamine (1a solution). Meanwhile, 115 μL of oleic acid was mixed with 5 mL of toluene (1b solution). Next, the MAPbBr ₃ : hexylamine solution was dropped dropwise into the toluene: oleic acid solution and stirred for 10 minutes to obtain a metal halide perovskite (MAPbBr ₃ ) nanocrystalline particle dispersion solution (second solution). .

Step 3: preparing a light emitting layer in which the perovskite nanocrystal layer is formed in the self-assembled polymer pattern

The metal halide perovskite (MAPbBr ₃ ) nanocrystalline particles dispersion solution prepared in step 2 was spin-coated on the substrate having the self-assembled polymer pattern prepared in step 1, and heat-treated at 70 ° C. for 10 minutes. A self-assembled polymer-perovskite light emitting layer in which a perovskite nanocrystal layer was formed in a cylinder-shaped self-assembled polymer pattern space was formed.

<Manufacture example 8>

Step 1: forming a self-assembled polymer pattern on the substrate

The self-assembled polymer pattern was formed on the silicon wafer substrate by the same method as in Step 1 of Preparation.

Step 2: preparing a metal halide perovskite nanocrystalline particle dispersion solution (hot-injection method)

0.08 g of Cs ₂ Co ₃ , 0.25 mL of oleic acid, and 3 mL of octadecene, a solvent, are mixed in a 3-necked flask, and the mixture is stirred with heating to 120 ° C. in an Ar atmosphere to prepare a Cs-oleate solution. (1c solution). Next, the Cs-oleate solution was maintained at 100 ° C. Then, 0.069 g of PbBr ₂ , 0.5 mL of oleic acid, 0.5 mL of hexylamine, and 5 mL of solvent octadecene were added to another three-neck flask, followed by mixing and heating to 150 ° C. in an Ar atmosphere to prepare a PbBr ₂ solution. 1d solution). Next, the Cs-oleate solution was injected into PbBr ₂ using a syringe (syringe) to react the two solutions for 5 seconds to prepare a dispersion solution of CsPbBr ₃ nanocrystal particles (second solution). After the reaction, the three-neck flask was cooled in an ice batch.

Step 3: preparing a light emitting layer in which the perovskite nanocrystal layer is formed in the self-assembled polymer pattern

The metal halide perovskite (CsPbBr ₃ ) nanocrystalline particles dispersion solution prepared in step 2 was spin-coated on the substrate having the self-assembled polymer pattern prepared in step 1, and heat-treated at 70 ° C. for 10 minutes. A self-assembled polymer-perovskite light emitting layer in which a perovskite nanocrystal layer was formed in a cylinder-shaped self-assembled polymer pattern space was formed.

< Production Example  9> Self-Assembly Polymers Perovskite Emitting layer  Light Emitting Diode Manufacturing

A PEDOT: PSS: PFI hole injection layer was formed by spin coating a mixture of PEDOT: PSS solution and PFI solution on a fluorine doped tin oxide (FTO) positive electrode.

Next, a self-assembled polymer-perovskite light emitting layer was prepared on the PEDOT: PSS: PFI hole injection layer by the method of Preparation Example 1.

Next, TPBI (1,3,5-Tris (1-Phenyl-1H-benzimidazol-2-yl) benzene) having a thickness of 50 nm on the self-assembled polymer-perovskite emitting layer is 1 × 10 ⁻⁶ Torr or less Deposited at a high vacuum of to form an electron transport layer.

Next, 1 nm thick LiF was deposited on the electron transport layer to form an electron injection layer.

Next, 100 nm thick aluminum was deposited on the electron injection layer to form a cathode, thereby manufacturing a self-assembled polymer-perovskite light emitting diode (regular structure).

The fabricated self-assembled polymer-perovskite light emitting diode showed an electroluminescence spectrum with a peak of 503 nm.

< Production Example  10>

In the self-assembled polymer-perovskite light emitting layer, a light emitting diode was manufactured in the same manner as in Example 9, except that the light emitting layer prepared in Preparation Example 2 was used.

< Production Example  11>

In the self-assembled polymer-perovskite emitting layer, a light emitting diode was manufactured in the same manner as in Preparation Example 9, except that the emitting layer prepared in Preparation Example 3 was used.

< Production Example  12>

Fluorine doped tin oxide (FTO) was used as a cathode, and ZnO was deposited to a thickness of 50 nm using a sputtering process as an electron transport layer on the cathode.

Next, a self-assembled polymer-perovskite light emitting layer was prepared by the method of Preparation Example 1 on the ZnO thin film.

Next, MoO ₃ was deposited on the self-assembled polymer-perovskite light emitting layer to a thickness of 5 nm at a high vacuum of 1 × 10 ⁻⁶ Torr or less as a hole transport layer.

Next, a positive electrode was formed by depositing Ag having a thickness of 100 nm on the hole transport layer, thereby fabricating a self-assembled polymer-perovskite light emitting diode (inverse structure).

The fabricated self-assembled polymer-perovskite light emitting diode showed an electroluminescence spectrum with a peak at 503 nm.

< Comparative example > Does not contain self-assembled polymer patterns Perovskite  Containing only nanocrystals Light emitting layer  Produce

As shown in FIG. 16, the metal halide perovskite solution prepared in Step 2 of Preparation Example 1 was spin coated on a silicon wafer substrate to form a metal halide perovskite thin film.

< Experimental Example > Emitting layer Photoluminescence  Property measurement

In order to determine the photoluminescence properties of the self-assembled polymer-perovskite light emitting layer according to the present invention, the following experiment was performed.

The photoluminescence properties of the self-assembled polymer-perovskite light emitting layer prepared in Preparation Example 1 and the perovskite light emitting layer prepared in Comparative Example were measured using a fluorophotometer, and the results are shown in FIG. 17. .

As shown in FIG. 17, the perovskite light emitting layer containing no self-assembled polymer showed photoluminescence at 517 nm, but the self-assembled polymer-perovskite light emitting layer according to the present invention showed photoluminescence at 503 nm.

Through this, it was confirmed that binding the perovskite nanocrystals in the self-assembled polymer pattern shifts the emission wavelength of the emission spectrum toward high energy.

Accordingly, the self-assembled polymer-perovskite emitting layer according to the present invention binds the perovskite nanocrystals into the self-assembled polymer pattern, thereby shifting the emission wavelength toward high energy, and improving the emission efficiency of the perovskite material. The self-assembled polymer located between the perovskite nanocrystal layers may prevent ion migration between the perovskite nanocrystal layers, thereby improving stability.

10: member for applying the light emitting layer
11: self-assembled polymer
12: perovskite nanocrystalline layer
13: organic layer
20: anode
23: hole injection layer
25: hole transport layer
40: light emitting layer
53: electron injection layer
55: electron transport layer
70: cathode

Claims (20)

A self-assembled polymer formed on the light emitting layer coating member and forming a pattern; And
Self-assembled polymer-perovskite light emitting layer comprising a perovskite nanocrystalline layer disposed inside the pattern of the self-assembled polymer.
The method of claim 1,
The self-assembled polymer is polyethylene oxide (PEO), polystyrene (PS), polycaprolactone (PCL), polyacrylonitrile (PAN), poly (methyl methacrylate) (PMMA), polyimide (Polyimide), polyvinyllidene fluoride (PVDF), Random copolymers and alternating copolymers consisting of two or more polymers selected from the group consisting of poly (n-vinylcarbazole) (PVK), polyvinylchloride (PVC), poly dimethylsiloxane (PDMS) and their respective derivatives Self-assembled polymer-perovskite light emitting layer, characterized in that the copolymer, a block copolymer (block copolymer) or a graft copolymer (graft copolymer).
The method of claim 1,
The pattern of the self-assembled polymer is a specific composition of a copolymer of two or more polymers expressed in the form of a cubic sphere, a cylinder, a gyroid, a lamella, or a combination thereof. Self-assembled polymer-perovskite light emitting layer, characterized in that formed by removing the polymer.
The method of claim 1,
Self-assembled polymer-perovskite light emitting layer, characterized in that the width of the self-assembled polymer pattern is 5 ~ 100 nm.
The method of claim 1,
The perovskite nanocrystals ABX ₃ or A _'2 A _{n - 1} BX _{3n +1} contains a structure of (n is an integer of 1 to 100), the A and A' are each an organic ammonium ion, an organic phosphine Is a phonium ion or an alkali metal ion, B is a transition metal, a rare earth metal, an alkaline earth metal, an organic substance, an inorganic substance, ammonium or a combination thereof, X is a halogen ion or a combination of different halogen ions, and the ion of A ' The radius is greater than the ion radius of A,
The organoammonium is an amidinium group organic ion or an organic ammonium cation, and the amidinium-based organic ion is formamidinium (CH (NH ₂ ) ₂ ) ion, acetamidinium, ( CH ₃ ) C (NH ₂ ) ₂ ) ion, guamidinium (C (NH ₂ ) ₃ ) ion, (C _n H _{2n + 1} ) (C (NH ₂ ) ₂ ) or (C _n F _{2n + 1} ) (C (NH ₂ ) ₂ ) and combinations or derivatives thereof, wherein the organic ammonium cation is CH ₃ NH ₃ , (C _n H _{2n + 1} ) _x NH _{4 -x} , ((C _n H _{2n + 1} ) _y NH _{3 -y} ) (CH ₂ ) _m NH ₃ , (C _n F _{2n + 1} ) _x NH _4-x , ((C _n F _{2n + 1} ) _y NH _3-y ) (CH ₂ ) _m NH ₃ , and combinations or derivatives thereof, wherein n and m are integers of 1 to 100, x is integers of 1 to 3, and y is 1 or 2, respectively.
The method of claim 1,
The self-assembled polymer-perovskite light emitting layer, characterized in that the size of the perovskite nanocrystals 1 to 990 nm.
The method of claim 1,
The light emitting layer is self-assembled polymer-perovskite light emitting layer further comprises an organic material layer surrounding the self-assembled polymer between the patterned self-assembled polymer and the perovskite nanocrystal layer.
The method of claim 7, wherein
The organic material used in the organic material layer is polyethylene oxide (PEO), polystyrene (PS), polycaprolactone (PCL), polyacrylonitrile (PAN), poly (methyl methacrylate) (PMMA), polydivinylbenzene (PDVB), polyimide (polyimide) Opene, polyaniline, polypyrrole, poly (3,4-ethylenedioxythiophene), polyvinyllidene fluoride (PVDF), poly (n-vinylcarbazole) (PVK), polyvinylchloride (PVC) and derivatives thereof Self-assembled polymer-perovskite light emitting layer, characterized in that any one, or a mixture of two or more.
The method of claim 7, wherein
Self-assembling polymer-perovskite light emitting layer, characterized in that the thickness of the organic layer is 1 ~ 20 nm.

Forming a self-assembled polymer pattern on the light emitting layer coating member (S100);
Forming a light emitting layer by forming a perovskite nanocrystal layer in the prepared self-assembled polymer pattern (S200); And
Heat-treating the light emitting layer (S300)
A method for producing the self-assembled polymer-perovskite light emitting layer of claim 1.
The method of claim 10,
After forming the self-assembled polymer pattern in the step S100, the step of forming an organic material layer on the patterned self-assembled polymer (S150) further comprising the step of manufacturing a self-assembling polymer-perovskite light emitting layer .
The method of claim 10,
The method for forming the perovskite nanocrystalline layer
Preparing a perovskite solution; And
Preparation of a self-assembled polymer-perovskite light emitting layer comprising the step of forming a perovskite nanocrystalline layer by coating and coating the perovskite solution in a self-assembled polymer pattern using a solution process Way.
The method of claim 12,
The perovskite solution is a method for producing a self-assembled polymer-perovskite light emitting layer, characterized in that the first solution in which the perovskite is dissolved or the second solution in which the perovskite nanocrystalline particles are dispersed. .
The method of claim 13,
The first solution is formed by mixing at least one of AX and A'X and BX ₂ (wherein A, A ', B and X are as defined in claim 5) in an aprotic solvent. Method for producing a self-assembled polymer-perovskite emitting layer.
The method of claim 13,
The second solution is a method of manufacturing a self-assembling polymer-perovskite light emitting layer, characterized in that prepared using the recrystallization method or hot-injection (hot-injection) method.
The method of claim 10,
When the perovskite nanocrystal layer is formed on the polymer pattern outside the pattern height of the self-assembled polymer, the step of removing the perovskite nanocrystal layer formed on the polymer pattern is further performed (S250). Method for producing a self-assembled polymer-perovskite light emitting layer, characterized in that.
The method of claim 16,
The step of removing the perovskite nanocrystal layer is performed by melting only the perovskite nanocrystal layer located on the self-assembled polymer pattern using a solvent for dissolving the perovskite nanocrystals and then removing the perovskite nanocrystal layer by spin coating. Method for producing a self-assembled polymer-perovskite light emitting layer, characterized in that.
Forming a self-assembled polymer pattern on the member (S100);
Preparing a perovskite nanopattern by forming a perovskite nanocrystal layer in the prepared self-assembled polymer pattern (S200); And
Heat-treating the perovskite nanopattern (S300)
Patterning method of perovskite thin film.
The method of claim 18,
After the perovskite nano-pattern is formed in step S200, the method for patterning the perovskite thin film further comprising the step of removing the self-assembled polymer.
A light emitting device comprising the light emitting layer of claim 1 selected from the group consisting of a light-emitting diode, a light-emitting transistor, a laser and a polarized light emitting device.

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