KR20220075102A - Water-stable fluorescent material, and fluorescent film and light emitting device containing the same, and method of manufacturing the same - Google Patents

Abstract

A fluorescent material stable to moisture, a fluorescent film and a light emitting device including the same, and a method for manufacturing the same are disclosed. The fluorescent material may include: an inorganic polymer matrix; hydrophobic fluorescent nanoparticles embedded in the inorganic polymer matrix; and a phenyl derivative bound to the surface of the inorganic polymer matrix. The fluorescent material has excellent stability against moisture, UV, and heat, as well as excellent curing properties with an encapsulant, and excellent stability and optical properties of a cured film or light emitting device. Therefore, it can be utilized in various fields such as LED and display.

Description

Moisture-stable fluorescent material, fluorescent film and light emitting device including same, and method for manufacturing the same

It relates to a fluorescent material, a fluorescent film and a light emitting device including the same, and a method for manufacturing the same.

CsPbX ₃ (X = Cl, Br, I) perovskite quantum dot material composed of inorganic materials has advantages such as excellent fluorescence efficiency and color purity, various colors by changing anion composition, and low-temperature synthesis method, so research on practical use is very good. is being actively pursued. However, its poor stability against moisture, UV, and heat is an obstacle to its practical use. In particular, as perovskite quantum dots are ionic crystals, they dissolve well in water and dissociate into ions, so they are extremely vulnerable to moisture.

In order to improve this, a powder in which perovskite quantum dots are embedded in an inorganic polymer matrix such as silica, alumina, or a compound of these two is prepared, or perovskite quantum dots are formed in the inorganic polymer beads having pores. Fluorescent powders with significantly improved stability to moisture, UV, and heat by preparing infiltration powder have been reported (eg, refer to non-patent literature J1, J2, and J3).

Silica and alumina powder are obtained through a sol-gel reaction of silica and alumina precursors, and since silica and alumina precursors undergo similar sol-gel reactions, they can be used separately or in combination. Alkoxysilane, perhydropolysilazane (PHPS), alkoxyaluminum, etc. are representative precursors of silica and alumina, but water is absolutely required to be converted to silica or alumina. If the sol-gel reaction of silica and alumina precursors is performed in the state in which perovskite quantum dots are added, a fluorescent powder in which quantum dots are embedded in silica and alumina matrices can be prepared. Therefore, in the state in which perovskite quantum dots are added, the sol-gel reaction of silica and alumina precursors is carried out using a trace amount of moisture naturally contained in a solvent or atmosphere, whereby the quantum dots are embedded in the matrix for a long time. During the embedding reaction, since perovskite quantum dots, which are ionic crystals, come into contact with moisture even in a trace amount, a decrease in fluorescence efficiency or fluorescence intensity is fundamentally unavoidable.

Fluorescent powders in which perovskite quantum dots are embedded in silica and alumina matrices exhibit better stability than the original perovskite quantum dots, but they do not yet secure sufficient stability to be applied to fluorescent films or light emitting devices. In addition, the most important thing for practical use is the stability of the fluorescent film or the light emitting device containing the fluorescent powder. That is, in order to utilize the fluorescent powder, the fluorescent powder containing quantum dots is mixed with an encapsulant and cured to produce a fluorescent film or a light emitting device. The stability of the manufactured film or device greatly influences its performance. . Nevertheless, there are few studies on long-term stability or driving stability of a fluorescent film or a light emitting device including a fluorescent powder containing perovskite quantum dots.

Accordingly, there is still a demand for development of a fluorescent material having excellent stability against moisture, UV, heat, and the like, and excellent curing properties together with an encapsulant.

J1. Hung-Chia Wang et. al, Mesoporous Silica Particles Integrated with All-Inorganic CsPbBr3 Perovskite Quantum-Dot Nanocomposites (MP-PQDs) with High Stability and Wide Color Gamut Used for Backlight Display. Angewandte Chemie International Edition 2016, 55, 7924-7929. J2. Shouqiang Huang et.al, Enhancing the Stability of CH3NH3PbBr3 Quantum Dots by Embedding in Silica Spheres Derived from Tetramethyl Orthosilicate in "Waterless" Toluene. Journal of the American Chemical Society 2016, 138, 5749-5752. J3. D. H. Park et. al, Facile synthesis of thermally stable CsPbBr3 perovskite quantum dot-inorganic SiO2 composites and their application to white light-emitting diodes with wide color gamut. Dyes and Pigments 2018, 149, 246-252.

One aspect of the present invention is to provide a fluorescent material having excellent stability against moisture, UV, and heat, and excellent curing properties with resin.

Another aspect of the present invention is to provide a fluorescent film including the fluorescent material.

Another aspect of the present invention is to provide a light emitting device including the fluorescent material.

Another aspect of the present invention is to provide a method for manufacturing the fluorescent material.

In one aspect of the present invention,

inorganic polymer matrix;

hydrophobic fluorescent nanoparticles embedded in the inorganic polymer matrix; and

a phenyl derivative bound to the surface of the inorganic polymer matrix;

A fluorescent material comprising:

The fluorescent material may further include, in the inorganic polymer matrix, hydrophobic basal particles having a nanopattern having a concave-convex structure formed on a surface thereof.

At least a portion of the hydrophobic fluorescent nanoparticles may be disposed in a concave portion of the concave-convex structure of the surface of the base particle to form a hybrid particle.

The phenyl derivative bound to the surface of the inorganic polymer matrix may be connected by a hydrocarbon chain having 1 to 6 carbon atoms.

The phenyl derivative bound to the surface of the inorganic polymer matrix can protect the embedded fluorescent nanoparticles by blocking open channels by the micropore network present in the inorganic polymer matrix.

According to another aspect of the present invention, there is provided a fluorescent film including the fluorescent material and the polymer.

According to another aspect of the present invention, there is provided a light emitting device including the fluorescent material.

According to another aspect of the present invention,

preparing a first solution by dispersing a first fluorescent powder including hydrophobic fluorescent nanoparticles embedded in an inorganic polymer matrix in an alcohol/toluene mixed solvent;

Preparing a second solution by adding and mixing a minimum amount of water and ammonia water necessary for the reaction to the first solution: And

sequentially adding an alkoxysilane precursor and a phenyl derivative precursor to the second solution at time intervals; and

reacting the mixed product;

There is provided a method of manufacturing the fluorescent material comprising a.

The fluorescent material according to an exemplary embodiment has excellent stability against moisture, UV, and heat, as well as excellent curing properties with an encapsulant, and excellent stability and optical properties of a cured film or light emitting device. Therefore, it can be utilized in various fields such as LED and display.

1 is a schematic cross-sectional view showing the microstructure of a conventional silica fluorescent powder containing perovskite quantum dots.
FIG. 2 is a schematic cross-sectional view showing the microstructure of a silica fluorescent powder in which particles in which conventional perovskite quantum dots and hydrophobic silica base particles are hybridized.
3 is a photograph and a fluorescence spectrum of the fluorescent material (PS ^* ) prepared in Example 1.
4 is a photograph and a fluorescence spectrum of the fluorescent material (SPS ^* ) prepared in Example 1. FIG.
5 is a photograph and a fluorescence spectrum of the fluorescent material (QS ^* ) prepared in Example 2.
6 is a photograph and a fluorescence spectrum of the fluorescent material (SQS ^* ) prepared in Example 2.
7a is a stability evaluation result when the PS and SPS fluorescent films prepared in Comparative Example 3 were put in water.
7b is a stability evaluation result when the PS ^* and SPS ^* fluorescent films prepared in Example 3 were put in water.
FIG. 8 is a result of evaluation of stability against UV of PS ^* and SPS ^* fluorescent films prepared in Example 3. FIG.
9 shows the results of stability evaluation at 85° C. of the PS ^* and SPS ^* fluorescent films prepared in Example 3 and the results of recovering fluorescence while stored at room temperature.
10 is a photograph of a white LED prepared from PS ^* and QS ^* in Example 4, and electroluminescence (EL) spectrum and color coordinates according to time after manufacture.
11 is an EL spectrum over time after manufacturing the white LED prepared from SPS ^* and SQS ^* in Example 4. FIG.
12 is an EL spectrum obtained while changing the applied current to the white LED prepared from PS ^* and QS ^* in Example 4. FIG.
13A is an EL spectrum when a 20 mA current is applied to the white LED prepared from PS ^* and QS ^* in Example 4 and driven for a long time.
13B is a measurement result of luminous efficacy when applying a current of 20 mA to the white LED prepared from PS ^* and QS ^* in Example 4 and driving it for a long time.

Hereinafter, the present invention will be described in detail with reference to the drawings. The accompanying drawings show exemplary embodiments of the present invention, which are provided only to help the understanding of the present invention, and the technical scope of the present invention is not limited thereby.

The present inventors found that the main reason that the conventional fluorescent powder and the fluorescent film and the light emitting device containing the fluorescent powder do not secure sufficient stability is, first, as shown in FIGS. 1 and 2, perovskite quantum dots or perovskite This is because the inorganic polymer matrix in which quantum dots and hydrophobic silica base particles are embedded together acts as an open channel with a 1 to 2 nm-sized ultra-fine pore network that is fundamentally possessed by the nature of the material. This is because the fluorescent powder composed of a polymer matrix has hydrophilicity, and thirdly, because the hydrophilic surface of the fluorescent powder is rough, when it is mixed with an encapsulant such as silicone resin and cured into a fluorescent film or a light emitting device accessory, the fluorescent powder and It was discovered that the encapsulant did not adhere and an empty microcavity was formed. In this way, cracks occur centered on the empty microcavity, and the generated cracks propagate to the surface of the film or device, impairing stability, especially stability against moisture.

In the case of perovskite quantum dots embedded in inorganic polymer beads having pores, the pores of the beads are open to the outside with a size of several nm to several tens of nm, and the van der Waals diameter of water molecules is 0.34 nm. Perovskite quantum dots may be vulnerable to moisture. A fluorescent powder prepared by embedding perovskite quantum dots in an inorganic polymer matrix exhibits more stable properties against moisture than perovskite quantum dots embedded in inorganic polymer beads. However, since the silica and alumina inorganic polymers exhibit hydrophilicity and are well dispersed in water, the stability of the perovskite quantum dots embedded in the inorganic polymer to moisture may be limited by the structural properties of the inorganic polymer. That is, the silica and alumina powders synthesized by the sol-gel reaction of the precursor are amorphous and form a network of micropores having a size of 1 nm to 2 nm, and these micropore networks form an open channel to the outside. However, these structural properties are hardly known to experts in fluorescent materials. The present inventors have recognized the above facts through long research and development, and even in the case of a fluorescent powder in which silica and alumina are embedded with quantum dots, these inorganic polymer matrices are amorphous, and ultrafine pores with a size of 1 nm to 2 nm network, and it was inferred that this ultrafine pore network constitutes an open channel to the outside (see FIGS. 1 and 2). For this reason, the fluorescent powders in which perovskite quantum dots are embedded in silica and alumina matrices show superior stability than the original perovskite quantum dots, but still do not secure sufficient stability to be applied to fluorescent films or light emitting devices. have.

Therefore, the present inventors block the ultrafine pore network channel present in the fluorescent powder containing the quantum dots to protect the quantum dots and at the same time provide hydrophobicity to the surface of the fluorescent powder, and mix well with the hydrophobic silicone encapsulant to cure the first phenyl derivative. A second fluorescent powder (PS ^* and SPS ^* ) bound to the surface of the fluorescent powder (PS and SPS) and a method for developing the same were developed.

For example, in the case of toluene having almost the same structure as a phenylmethyl group among phenyl derivatives, it is known that the van der Waals diameter is 0.56 nm. Assuming that the molecular length increases by approximately 0.1 nm when the carbon chain is increased one by one, the phenyl derivatives linked to the hydrocarbon chain having 1 to 6 carbons have a molecular length of 0.56 to 1.06 nm, so the size of 1 to 2 nm Phenyl derivatives bound to the micropore entrance of In addition, since it has hydrophobicity, it will repel water and will be cured with excellent adhesion to the hydrophobic encapsulant. As a result, it is possible to provide a fluorescent material and a film and device including the same, which have significantly improved stability against moisture, UV, and heat, particularly moisture, and provide excellent optical properties.

Usually, the sol-gel reaction of alkoxysilane is, for example, 4.5 mL of distilled water and 3 mL of NH ₄ OH in 100 mL of ethanol solvent, add sufficient amount of water and catalyst, add alkoxysilane, and then react at 25 °C for about 3 hours at room temperature. have. The reaction of binding a phenyl derivative to PS and SPS, which are the first fluorescent powders, is also a kind of sol-gel reaction. However, it was confirmed that all fluorescence immediately disappeared when the reaction of combining phenyl derivatives with PS and SPS fluorescent powders was performed under conditions similar to the sol-gel reaction of alkoxysilane. This is because water and ammonia water enter the interior through the open channels of PS and SPS phosphors and dissolve the embedded ionic fluorescent nanocrystals.

In order to solve this problem, the present inventors dispersed the first fluorescent powder PS sufficiently dried by vacuum and heat treatment at 85° C. in a mixed solvent of alcohol and toluene, for example, ethanol/toluene (eg, 2/1 by volume) to reduce hydrophobicity. After adding and mixing only the minimum amount of water and ammonia water required for the reaction (for example, 1/7 or less concentration), the alkoxysilane to which the alkoxysilane and the phenyl derivative are combined at a certain time interval (for example, 2 to 5 minutes) By adding a phenyl derivative to PS and SPS, which are the first fluorescent powders, the second fluorescence is obtained while preserving the ionic fluorescent nanocrystals, perovskite quantum dots, and their fluorescence properties by performing the sol-gel reaction within a short time (eg, 2 hours). We were able to succeed in producing the powders PS ^* and SPS ^* .

Fluorescent material according to an embodiment,

inorganic polymer matrix;

hydrophobic fluorescent nanoparticles embedded in the inorganic polymer matrix; and

and phenyl derivatives bound to the surface of the inorganic polymer matrix.

The phenyl derivative bonded to the surface of the inorganic polymer matrix may include a phenyl group bonded to a Si atom by 1 to 6 hydrocarbon chains.

The phenyl derivative may be a compound represented by Formula 1 below.

<Formula 1>

R ₁ Si(OR ₂ ) ₃

In the above formula, R ₁ is an alkyl group having 1-6 carbon atoms to which a phenyl group is bonded, and R ₂ is an alkyl group having 1-4 carbon atoms.

For example, the phenyl derivative may be phenylethyltrimethoxysilane.

The phenyl derivative bound to the surface of the inorganic polymer matrix protects the fluorescent nanoparticles contained therein by blocking the ultrafine pore network channels that are formed by the structural properties of the fluorescent powder, that is, present in the inorganic polymer matrix, and provides hydrophobicity to the fluorescent powder. , it improves stability against moisture, and adheres well to the hydrophobic silicone resin, so it is possible to improve adhesion with the hydrophobic encapsulant. Accordingly, it is possible to provide a fluorescent film and a light emitting device having remarkably improved stability to moisture by using the fluorescent material.

The hydrophobic fluorescent nanoparticles embedded in the inorganic polymer matrix may be embedded alone without hydrophobic base particles having a nanopattern of a concave-convex structure formed on the surface.

According to an embodiment, the inorganic polymer matrix may further include hydrophobic basal particles having a nanopattern having a concave-convex structure on a surface thereof.

In the fluorescent material, the base particle may be made of an inorganic material having a refractive index higher than that of air and lower than that of light emitting nanoparticles, and may include, for example, silica, alumina, or a combination thereof, but is not limited thereto.

A first hydrophobic functional group or ligand may be included on the surface of the base particle, and a second hydrophobic functional group or ligand may be included on the surface of the fluorescent nanoparticle. In this case, the first hydrophobic functional group or ligand on the surface of the base particle and A physical bond may be formed between the second hydrophobic functional group or the hydrophobic ligand on the surface of the fluorescent nanoparticles.

The first hydrophobic functional group or ligand bound to the surface of the base particle may include, for example, a hydrocarbon chain having 6 to 20 carbon atoms. The first hydrophobic functional group or ligand may further include at least one functional group selected from, for example, an unsubstituted C6-C20 alkyl group, an unsubstituted C6-C20 alkenyl group, and an unsubstituted C6-C20 alkynyl group.

The average particle diameter of the hydrophobic base particles may be, for example, 50 nm to 200 nm.

In the fluorescent material, the fluorescent nanoparticles may include at least one selected from the group consisting of perovskite nanocrystals, group II-VI compound semiconductor nanocrystals, group III-V compound semiconductor nanocrystals, and inorganic phosphors. .

The perovskite nanocrystals may include, for example, an ABX ₃ structure, but is not limited thereto.

Here, A and B may include a metal selected from the group consisting of alkali metals, alkaline earth metals, transition metals, and lanthanum groups having different sizes and combinations thereof. A and B are, for example, cesium (Cs), lead (Pb), titanium (Ti), strontium (Sr), calcium (Ca), barium (Ba), yttrium (Y), gadolinium (Gd), lanthanum It may include a material selected from the group consisting of (La), iron (Fe), manganese (Mn), sodium (Na), potassium (K), rubidium (Rb), and combinations thereof.

The X may include oxygen or halogen elements (F, Cl, Br, I).

The B may be combined with X in the form of a corner-sharing octahedron of 6-fold coordination.

The perovskite nanocrystals may be, for example, metal halide perovskite represented by CsPbX ₃ , wherein X is Cl, Br or I.

Group II-VI compound semiconductor nanocrystals may include, for example, at least one selected from the group consisting of CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, HgS, HgSe, and HgTe.

Group III-V compound semiconductor nanocrystals may include, for example, at least one selected from the group consisting of GaN, GaP, GaAs, InP, and InAs.

The inorganic phosphor is, for example, La ₂ O ₂ S:Eu, Li ₂ Mg(MoO ₄ ):Eu,Sm, (Ba, Sr) ₂ SiO ₄ :Eu, ZnS:Cu,Al, SrGa ₂ S ₄ :Eu , Sr ₅ (PO ₄ ) ₃ Cl:Eu, (SrMg) ₅ PO ₄ Cl:Eu, BaMg ₂ Al ₁₆ O ₂₇ :Eu, Na(Y,Gd,Ln)F ₄ :(Yb,Er) (where Ln is any one selected from the group containing at least one lanthanide element other than Yb and Er) and Na(Y,Gd,Ln)F ₄ of a core/shell structure: (Yb,Er)/Na(Gd,L) F ₄ : (Ce, Tb) (wherein L is any one selected from the group consisting of Yb, Er, lanthanide elements other than Ce and Tb or Y) can

The fluorescent nanoparticles may have a core/shell structure of at least one of the following (1) to (3). In addition, an intermediate layer including an alloy of the core material and the shell material may be further included between the core and the shell.

(1) Group II-VI compound semiconductor nanocrystals (core) / Group II-VI compound semiconductor nanocrystals (shell);

(2) group III-V compound semiconductor nanocrystals (core) / group III-V compound semiconductor nanocrystals (shell);

(3) Group III-V compound semiconductor nanocrystals (core)/Group II-VI compound semiconductor nanocrystals (shell).

The group II-VI compound semiconductor nanocrystal (core)/group II-VI compound semiconductor nanocrystal (shell) structure includes, for example, CdSe/ZnS, and the group III-V compound semiconductor nanocrystal (core) / Group III-V compound semiconductor nanocrystal (shell) structure includes, for example, InP/GaN, and the group III-V compound semiconductor nanocrystal (core)/ Group II-VI compound semiconductor nanocrystal (shell) structure As the example, there may be InP/ZnS, and the like, but is not limited thereto.

The second hydrophobic functional group or ligand bound to the surface of the fluorescent nanoparticle includes, for example, a hydrocarbon chain having 6 to 20 carbon atoms. The second hydrophobic functional group or ligand may have, for example, a functional group such as R(CH ₃ ) ₂ NBr, R-NH ₂ , R-SH, R-CO ₂ H, R ₃ -P, R ₃ -PO, etc.; wherein R may be a C6-C20 alkyl chain, However, the present invention is not limited thereto.

The average particle diameter of the fluorescent nanoparticles is not particularly limited, but is preferably in a range that can be fitted into the concave portion of the base particle, for example (1) 3 nm to 15 nm. In the above range, the possibility of hybridization with the fluorescent nanoparticles increases over a large area along the concave-convex structure of the surface of the base particle. For example, when the average particle diameter of the fluorescent nanoparticles is (1) 3 nm to 10 nm, there is a tendency to maintain a state in which the fluorescent nanoparticles are embedded, that is, a hybrid state, over a large area along the uneven structure of the surface of the base particle. can prevail. When the average particle diameter of the fluorescent nanoparticles is 10 nm to 15 nm, the fluorescent nanoparticles may be inserted into the concave portion of the surface of the base particle and some may be removed. However, when the average particle diameter of the fluorescent nanoparticles is greater than 15 nm, the fluorescent nanoparticles cannot be hybridized with the base particles because they are not initially fitted into the concave portion of the surface of the base particles.

The fluorescent material may further include metal nanoparticles including Au, Ag, alloys thereof, or a combination thereof, together with the fluorescent nanoparticles. When the fluorescent nanoparticles and the metal nanoparticles, such as gold nanoparticles, are mixed, fluorescence may further increase due to a plasmon effect. The metal nanoparticles may be disposed together with the fluorescent nanoparticles in a concave portion of the nanopattern of the concave-convex structure on the surface of the base particle.

In the fluorescent material, the inorganic polymer matrix may include, for example, silica, alumina, or a combination thereof, but is not limited thereto. The inorganic polymer matrix may be made of the same material as the base particles. When the inorganic polymer matrix and the base particles are made of the same material, the bonding force to the base particles is excellent and cracking can be significantly suppressed.

The fluorescent material may have a powder form. The fluorescent material in powder form is easily mixed with the polymer material to form a fluorescent film.

The fluorescent material inhibits aggregation of fluorescent nanoparticles to prevent cracks, and has better stability against moisture, UV, and heat, as well as excellent fluorescence intensity and optical properties. This can be used in various fields such as LEDs and displays.

In another embodiment of the present invention, there is provided a fluorescent film including the fluorescent material and the polymer.

In another embodiment of the present invention, a light emitting device including the fluorescent material is provided. The light emitting device may be, for example, a light emitting diode, a light emitting transistor, a laser, or a polarized light emitting device, but is not limited thereto.

A method of manufacturing a fluorescent material according to another embodiment of the present invention,

preparing a first solution by dispersing a first fluorescent powder including hydrophobic fluorescent nanoparticles embedded in an inorganic polymer matrix in an alcohol/toluene mixed solvent;

Preparing a second solution by adding and mixing a minimum amount of water and ammonia water necessary for the reaction to the first solution: And

sequentially adding an alkoxysilane precursor and a phenyl derivative precursor to the second solution at time intervals; and

and reacting the mixed product.

The first solution may further include hydrophobic basal particles having a nanopattern of a concave-convex structure formed on a surface thereof.

Both the first solution and the second solution may use a mixed organic solvent. The mixed organic solvent may be an alcohol/toluene mixed solvent. For example, the mixed organic solvent may be an ethanol/toluene mixed solvent. The reason for using such a mixed organic solvent is to increase the hydrophobicity of the solvent to protect the first fluorescent powder, which is a reactant, and to disperse the second fluorescent powder, which is a product, well. Inorganic polymer matrix powder embedded with fluorescent nanoparticles such as perovskite quantum dots can dissolve quantum dots, which are ionic crystals, when water moves through micropore network channels. It is possible to protect the embedded fluorescent nanoparticles only when the reaction is completed in the shortest time using a solvent that is as hydrophobic as possible while using a catalyst and mixing them well. For example, after reacting the mixed product at room temperature for 1.5 hours, the reaction may be terminated by reacting within 2 hours by raising the temperature to 30° C. and reacting for 0.5 hours.

The manufacturing method of the fluorescent material may further include the step of pulverizing the resultant in bulk form obtained in the drying step, and may be provided as a fluorescent material in powder form.

Exemplary embodiments are described in more detail through the following examples and comparative examples. The following examples are provided to make the present invention more clear and easily understood, so the scope of the present invention is not limited by these examples.

Preparation Example 1: Preparation of hydrophobic perovskite quantum dots (P) and hydrophobic nanostructured silica (S)

Hydrophobic perovskite quantum dots (hereinafter referred to as “P”) to be used for preparing a fluorescent powder containing quantum dots and nanostructured hybrid particles or mixed particles in Preparation Example 2 to be described later were prepared in the literature [J. Song et. al, Room-Temperature Triple-Lgand Surface Engineering Synergistically Boosts Ink Stability, Recombination Dynamics, and Charge Injection toward EQE-11.6% Perovskite QLEDs. Advanced Materials 2018, 30, 1800764], and the purification method was improved and used for the manufacturing process of the present invention. That is, after centrifugation by adding methyl acetate instead of ethyl acetate to the synthetic stock solution, it was dispersed in toluene (6.2 mg/mL) and stored without further washing with water, and used in small portions whenever necessary. A TEM image of this sample was obtained and the size of the particles was confirmed. As a result, the average was 11 nm, and when the quantum efficiency was measured, it was 55%.

On the other hand, hydrophobic nanostructured silica (hereinafter referred to as "S") to be used in Preparation Examples 2 to 3 to be described later was prepared as follows.

After adding 9 mL of distilled water and 6 mL of NH ₄ OH to 400 mL of ethanol and stirring well for 30 minutes, 5.3 mL of tetraethoxysilane and 2.3 mL of octadecyltrimethoxysilane were simultaneously added and stirred for 1 day (Day 1). 9 mL of distilled water and 6 mL of NH ₄ OH were added to this solution, and after stirring well for 30 minutes, 5.3 mL of tetraethoxysilane and 2.3 mL of octadecyltrimethoxysilane were simultaneously added and stirred for 1 day (day 2). Then, 400 mL of ethanol, 9 mL of distilled water, and 6 mL of NH ₄ OH were added to the solution and stirred well for 30 minutes, then 5.3 mL of tetraethoxysilane and 2.3 mL of octadecyltrimethoxysilane were simultaneously added and stirred for 1 day. (Day 3). After adding 9 mL of distilled water and 6 mL of NH ₄ OH to this solution, and stirring well for 30 minutes, 5.3 mL of tetraethoxysilane and 2.3 mL of octadecyltrimethoxysilane were simultaneously added and stirred for 1 day (day 4). To the solution, 200 mL of ethanol, 9 mL of distilled water, and 6 mL of NH ₄ OH were added and stirred well for 30 minutes, then 5.3 mL of tetraethoxysilane and 2.3 mL of octadecyltrimethoxysilane were simultaneously added and stirred for 1 day (No. 5). Work).

The hydrophobic nanostructured silica (S) particles obtained by centrifuging this solution were washed once with 40 mL of ethanol and once with a mixed solution of 25 mL of ethanol and 15 mL of chloroform, and the centrifuged particles were dispersed in 40 mL of chloroform. (0.051 g/mL) and used by taking a small amount whenever necessary. The average size of the nanostructured silica particles was 146 nm.

Preparation Example 2: Preparation of fluorescent powders (PS and SPS) containing perovskite quantum dots (P) and hybrid particles of quantum dots and hydrophobic nanostructured silica (S)

To prepare PS fluorescent powder, dilute the perovskite quantum dot (P) solution with toluene to prepare 5 mL of a 1 mg/mL solution, and after stirring for 2 hours or more, PHPS solution (Perhydropolysilazane 18.6 wt% in dibutyl ether) 2 mL and 0.002 mL of NH ₄ OH catalyst were added. The vial containing this solution was placed in a water bath at 60 °C equipped with a magnetic stirrer. 0.18 mL of distilled water as a reactant was added to the solution 6 times at 10-minute intervals and stirred for a total of 70 minutes. The solution was taken out of the water bath and left at room temperature in the dark for 150 minutes to complete the gelation reaction. To the solution was further centrifuged using 3 mL of toluene, put in a vacuum desiccator and dried for 3 hours or more. The sample was ground in a mortar and pulverized, and then dried in an oven at 85° C. for 3 hours to prepare 0.369 g of PS powder.

In order to prepare the SPS fluorescent powder, the solution corresponding to 0.11 g of the hydrophobic nanostructured silica (S) particles synthesized in Preparation Example 1 was subjected to ultrasonic bath and vortex treatment to increase dispersibility, and then dried by connecting to a vacuum. On the other hand, dilute the perovskite quantum dot (P) solution with toluene to prepare 5 mL of a 1 mg/mL solution, and after stirring for 2 hours or more, add the hydrophobic nanostructured silica particles dried above, and ultrasonic bath treatment within 5 minutes After that, gently stir overnight. 2 mL of PHPS solution and 0.002 mL of NH ₄ OH catalyst were added to the solution. The vial containing this solution was placed in a water bath at 60 °C equipped with a magnetic stirrer. The reactant, 0.18 mL of distilled water, was added 6 times at 10-minute intervals and stirred for a total of 70 minutes. The solution was taken out of the water bath and left at room temperature in the dark for 150 minutes to complete the gelation reaction. To the solution was further centrifuged using 3 mL of toluene, put in a vacuum desiccator and dried for 3 hours or more. The sample was ground in a mortar and pulverized, and then dried in an oven at 85° C. for 3 hours to prepare 0.471 g of SPS powder.

Preparation Example 3: Preparation of quantum dots (Q) and fluorescent powders (QS and SQS) containing hybrid particles of quantum dots and hydrophobic nanostructured silica (S)

To prepare QS fluorescent powder, prepare 5 mL of a 1 mg/mL solution by diluting a CdSe/ZnS core/shell structured quantum dot (Q, manufactured by Zeus) solution with toluene. After stirring for 2 hours or more, 2 mL of PHPS solution was added. added. The vial containing this solution was placed in a water bath at 60 °C equipped with a magnetic stirrer. 0.18 mL of distilled water as a reactant was added to the solution 6 times at 10-minute intervals and stirred for a total of 70 minutes. The solution was taken out of the water bath and left at room temperature in the dark for 150 minutes to complete the gelation reaction. To the solution was further centrifuged using 3 mL of toluene, put in a vacuum desiccator and dried for 3 hours or more. The sample was ground in a mortar and pulverized, and then dried in an oven at 85° C. for 3 hours to prepare 0.356 g of PS powder.

To prepare the SQS fluorescent powder, the solution corresponding to 0.11 g of the hydrophobic nanostructured silica (S) particles synthesized in Preparation Example 1 was subjected to ultrasonic bath and vortex treatment to increase dispersibility, and then dried by connecting to a vacuum. On the other hand, dilute the quantum dot (Q) solution with CHCl ₃ solvent to prepare 5 mL of a 1 mg/mL solution, and after stirring for 2 hours or more, add the hydrophobic nanostructured silica particles dried above, and ultrasonic bath treatment within 5 minutes , gently stirred overnight. 2 mL of PHPS solution was added to the solution. The vial containing this solution was installed in a water bath at 60 °C equipped with a magnetic stirrer. The reactant, 0.18 mL of distilled water, was added 6 times at 10-minute intervals and stirred for a total of 70 minutes. The solution was taken out of the water bath and left at room temperature in the dark for 150 minutes to complete the gelation reaction. To the solution was further centrifuged using 3 mL of toluene, put in a vacuum desiccator and dried for 3 hours or more. The sample was ground in a mortar and pulverized, and then dried in an oven at 85° C. for 3 hours to prepare 0.405 g of SQS powder.

All processes were carried out while minimizing the time the quantum dots were exposed to light.

Example 1: Fluorescent powder (PS) containing perovskite quantum dot particles (P) and nanostructured hybrid particles (SP) and bound to a phenyl derivative (PS) ^* and SPS ^* ) Produce

0.25 g of the PS fluorescent powder synthesized in Preparation Example 2 was dispersed in 75 mL of a mixed solvent of ethanol/toluene (2/1). To the dispersion solution, 0.45 mL of distilled water and 0.3 mL of NH ₄ OH were added and stirred for 5 minutes. After adding 0.21 mL of tetraethoxysilane and stirring for 2 minutes, 0.09 mL of phenylethyltrimethoxysilane was added, stirring at room temperature for 1.5 hours, and then stirring for 0.5 hours in a water bath at 30 ° C. shortened. After centrifuging the solution and washing the solid with 10 mL of ethanol, it was vacuum dried for 3 hours or more, and dried in an oven at 85° C. for 2 hours to prepare 0.243 g of PS ^* fluorescent powder.

To prepare the SPS ^* fluorescent powder, 0.42 g of the SPS fluorescent powder synthesized in Preparation Example 2 was dispersed in 126 mL of an ethanol/toluene (2/1) mixed solvent. To the dispersion solution, 0.75 mL of distilled water and 0.5 mL of NH ₄ OH were added and stirred for 5 minutes. After adding 0.35 mL of tetraethoxysilane and stirring for 2 minutes, 0.15 mL of phenylethyltrimethoxysilane was added and stirred at room temperature for 1.5 hours, followed by further stirring in a water bath at 30° C. for 0.5 hours to shorten the reaction time. The solution was centrifuged and the solid was washed with 10 mL of ethanol, dried in vacuum for 3 hours or more, and dried in an oven at 85° C. for 2 hours to prepare 0.397 g of SPS ^* fluorescent powder.

The reason why the PS ^* and SPS ^* fluorescent powders prepared by the surface modification described above has a smaller amount than the reactive materials PS and SPS powders is that the prepared PS ^* and SPS ^* fluorescent powders have strong acid hydrophobicity due to the phenyl derivative on the surface. This is because the static electricity was so severe that some powder was lost during drying and yield measurement.

The quantum efficiencies of the PS ^* and SPS ^* fluorescent powders prepared by the above surface modification were 23% and 22%, and actual images and fluorescence spectra with and without UV are shown in FIGS. 3 and 4 .

In the above, the quantum efficiency measured in the powder state of PS ^* and SPS ^* fluorescent powder is somewhat low, but the quantum efficiency has a large error depending on the concentration and measurement method of the contained fluorescent nanoparticles. Since the luminous intensity and luminous efficiency in the state are excellent, it is recorded only for reference.

Example 2: Fluorescent powder (QS) containing quantum dot particles (Q) and nanostructured hybrid particles (SQ) and bound to a phenyl derivative (QS) ^* and SQS ^* ) Produce

0.26 g of the QS fluorescent powder synthesized in Preparation Example 3 was dispersed in 75 mL of an ethanol/toluene (2/1) mixed solvent. To the dispersion solution, 0.45 mL of distilled water and 0.3 mL of NH ₄ OH were added and stirred for 5 minutes. 0.21 mL of tetraethoxysilane was added and stirred for 2 minutes, then 0.09 mL of phenylethyltrimethoxysilane was added, stirred at room temperature for 1.5 hours, and then stirred in a water bath at 30° C. for 0.5 hours to shorten the reaction time. The solution was centrifuged and the solid was washed with 10 mL of ethanol, dried under vacuum for 3 hours or more, and dried in an oven at 85° C. for 2 hours to prepare 0.230 g of QS ^* fluorescent powder.

To prepare the SQS ^* fluorescent powder, 0.20 g of the SQS fluorescent powder synthesized in Preparation Example 3 was dispersed in 60 mL of an ethanol/toluene (2/1) mixed solvent. 0.36 mL of distilled water and 0.24 mL of NH ₄ OH were added to the dispersion solution and stirred for 5 minutes. After adding 0.168 mL of tetraethoxysilane and stirring for 2 minutes, 0.072 mL of phenylethyltrimethoxysilane was added, stirring at room temperature for 1.5 hours, and then stirring in a water bath at 30° C. for 0.5 hours to shorten the reaction time. The solution was centrifuged and the solid was washed with 10 mL of ethanol, dried in a vacuum for 3 hours or more, and dried in an oven at 85° C. for 2 hours to prepare 0.197 g of SQS ^* fluorescent powder.

The reason why the QS ^* and SQS ^* fluorescent powders prepared by combining phenyl derivatives in the above is less than the reactant QS and SQS powders is that the prepared QS ^* and SQS ^* fluorescent powders have strong acid hydrophobicity due to the phenyl derivative on the surface. This is because the static electricity was so severe that some powder was lost during drying and yield measurement.

The quantum efficiencies of the QS ^* and SQS ^* fluorescent powders prepared by surface modification were 93% and 127%, and actual images and fluorescence spectra with and without UV are shown in FIGS. 5 and 6 .

Example 3: Phenyl derivative-conjugated fluorescent powder (PS ^* and SPS ^* ) to prepare a fluorescent film containing

A polymer film containing the PS ^* and SPS ^* fluorescent powders prepared in Example 1 was prepared as follows.

The PS ^* and SPS ^* fluorescent powders were mixed together with a silicone resin OE6630 A/B (1/4) mixture in a weight ratio of 100:8, respectively, to remove air bubbles. On a slide glass having an area of 1.5 cm × 1.5 cm, a predetermined amount of the mixture from which the air bubbles were removed was placed on a glass slide to make it flat. After that, all the specimens were heated in an oven at 85° C. for 1 hour, and heated to 120° C. for 1 hour to prepare a fluorescent film.

Since the curing conditions coincide with the conditions for manufacturing the white LED in Example 4 to be described later, the stability evaluation results may be complementary to each other.

Comparative Example 3: Preparation of Fluorescent Film Containing Phenyl Derivative-Free Fluorescent Powders (PS and SPS)

Each fluorescent film was prepared in the same manner as in Example 3 except that the PS and SPS fluorescent powders prepared in Preparation Example 2 were mixed with the silicone resin OE6630 A/B (1/4) mixture in a weight ratio of 100:3, respectively. .

For reference, in the same manner as in Example 3, when PS and SPS fluorescent powders are mixed with a silicone resin OE6630 A/B (1/4) mixture in a weight ratio of 100:8, respectively, and thermal curing is performed, curing does not proceed properly and is opaque and non-uniform. As a single material, comparative evaluation was impossible.

Comparative Example 4: Preparation of a fluorescent film using perovskite quantum dot particles (P) as it is

For reference, a film was prepared in the same manner as in Preparation Example 3, except that the P solution was added at a molar ratio twice thicker than PS and mixed with OE6630 A/B (1/4) to remove the solvent and air bubbles.

In Example 3 and Comparative Example 3, the fluorescent films prepared by putting PS ^* , SPS ^* and PS, SPS emitted green fluorescence after heat treatment, whereas the perovskite quantum dot (P) solution of Comparative Example 4 was directly added The prepared film was in an unusable state because fluorescence was almost extinguished (see P film in the photos of FIGS. 8 and 9). Since it was found that the stability to heat was very weak to use the perovskite quantum dots as they are in the manufacture of the fluorescent film, further stability studies were not conducted on the film containing only the quantum dots (P). In addition, since the fluorescent film prepared by adding PS and SPS fluorescent powder in Comparative Example 3 has a hydrophilic property, only stability to moisture was investigated for comparison.

On the other hand, in Example 3, the fluorescent film prepared by adding PS ^* and SPS ^* fluorescent powder was investigated for stability against moisture, UV, and heat as follows. Hereinafter, PS ^* , SPS ^* and the fluorescent film prepared by putting PS and SPS will be conveniently referred to as PS ^* , SPS ^* film and PS, SPS film.

Evaluation Example 1: Evaluation of the stability of fluorescent films against moisture, UV, and heat

(1) Stability evaluation against moisture

In order to evaluate the stability against moisture, first, the slide glass set to which the PS and SPS films of Comparative Example 3 are attached is immersed in water, and then the results of observation with the naked eye while irradiating UV over time are photographed as shown in FIG. 7a. indicated.

As shown in FIG. 7a, when observed with the naked eye, the PS and SPS films of Comparative Example 3 showed stable behavior for the first 4 hours, but after 8 hours, PS first started to lose fluorescence, and after 1 day, PS, SPS The fluorescence decreased noticeably in both films.

On the other hand, the PS ^* , SPS ^* film of Example 3 could not visually observe any decrease in fluorescence even after one day while submerged in water. Therefore, the film was taken out, the fluorescence spectrum was measured, and it was observed until the 16th day while submerged in water again. Each fluorescence peak area was obtained over time and divided by the fluorescence peak area of the first time to measure the change in fluorescence intensity over time, and the results are shown in FIG. 7B . As shown in Fig. 7b, the PS ^* , SPS ^* film of Example 3 (Fig. 7b) not only showed incomparably stable behavior with the PS and SPS films of Comparative Example 3 (Fig. 7a), but rather the fluorescence intensity It showed surprising behavior, which increased by 10 to 20% compared to before submersion.

(2) Stability evaluation against UV

In order to evaluate the stability to UV, the PS ^* , SPS ^* film set of Example 3 was turned on at a distance of 5 cm with 6 W UV (365 nm) on and the fluorescence spectrum was measured over time. Each fluorescence peak area was obtained over time and divided by the fluorescence peak area of the first time to measure the change in fluorescence intensity over time, and the results are shown in FIG. 8 . The first fluorescence photograph and the fluorescence photograph after 134 hours are also shown in FIG. 8 .

As shown in FIG. 8 , both the PS ^* and SPS ^* films showed no significant change in luminescence intensity within the error range for 134 hours.

(3) thermal stability evaluation

In order to evaluate the stability to heat, a set of PS ^* and SPS ^* films of Example 3 were placed in an oven heated to 85° C. in advance, and fluorescence spectra were measured over time up to 134 hours. After 134 hours, the film was stored at dark room temperature for up to 17 days, and fluorescence spectra were measured according to the date. Each fluorescence peak area was obtained and divided by the fluorescence peak area of the initial time to measure the change in fluorescence intensity over time, and the results are shown in FIG. 9 together with a fluorescence photograph. In the graph of FIG. 9, the left side of the wave pattern evaluates the change in fluorescence intensity with respect to heat at 85 °C, and the right side evaluates the performance of recovering the fluorescence properties while keeping the film evaluated at 85 °C for 134 hours at room temperature. .

As shown in FIG. 9 , both PS ^* and SPS ^* films showed similar behavior in which the fluorescence intensity decreased with time. After 134 hours, the PS ^* film of Example 3 maintained 52% of the original fluorescence intensity and the SPS ^* film maintained 42% of the original fluorescence intensity. Interestingly, if the films were stored at room temperature, the PS ^* film after 17 days 87% of the fluorescence intensity and the SPS ^* film recovered 72% of the original fluorescence intensity. Based on the experience so far, it is predicted that the fluorescence intensity will recover steadily for up to one month. It can be said that both films exhibit very good thermal stability.

Example 4: Fluorescent powder to which a phenyl derivative is bound (PS) ^* , QS ^* set and SPS ^* , SQS ^* white LED manufacturing containing set)

The green PS ^* and red QS ^* fluorescent powder sets and the green SPS ^* and red SQS ^* fluorescent powder sets prepared in Examples 1 and 2 were mixed with a silicone resin, respectively, and a blue LED chip (East LED Ltd., AL051) It was placed on top to produce a white LED as shown below.

The green PS ^* and red QS ^* fluorescent powders were mixed with a silicone resin OE6630 A/B (1/4) mixture in a weight ratio of 16:5:200 (green:red:resin), respectively, and vacuum was connected to remove air bubbles. It is convexly filled in the cup structure of the blue LED chip. The green SPS ^* and red SQS ^* fluorescent powders were also convexly filled in the cup structure of the blue LED chip in the same weight ratio and method as above. After that, all the LED chips were heated in an oven at 85° C. for 1 hour, and then heated to 120° C. for 1 hour to prepare a white LED.

In the above, various ratios were tried to find the weight ratio of green fluorescent powder: red fluorescent powder: silicone resin for making a white LED, and only the optimal conditions were recorded in the present invention.

Comparative Example 4: Preparation of white LED containing fluorescent powder (PS, QS set and SPS, SQS set) before surface modification

An attempt was made to make white light by mixing the fluorescent powders (PS, QS set, and SPS, SQS set) prepared in Preparation Examples 2 and 3 and putting them on a blue LED, but 16:5:200 (green fluorescent powder: red) At the fluorescent powder concentration of the fluorescent powder: silicone resin) weight ratio, curing was not completed, and an opaque and uneven LED chip was produced, which was judged not to be evaluated.

Evaluation Example 2: Stability evaluation of the manufactured white LED for long-term stability, applied current, and driving time

(1) Stability evaluation for long-term stability

In Example 4, the white LED manufactured using the green PS ^* and red QS ^* fluorescent powder set was connected to a total luminous flux measuring device (LEOS OPI 100) and an electroluminescence (EL) spectrum and luminous efficiency (luminous) spectrum were applied while a current of 20 mA was passed. efficacy) was measured. After production, the trend was measured for 4 months while stored at room temperature, and it is shown in FIG.

After heat curing and storing at room temperature, the EL increased significantly for up to 1 month, then showed a slight increase and then stabilized, and the color coordinates shifted to the central white light. The phosphor had a yellow color under normal light and emitted white light when an electric current was applied, and the highest luminous efficiency measured at 20 mA and 2.71 V was 43.2 lm/W.

Similarly, in Example 4, the white LED prepared using the green SPS ^* and the red SQS ^* fluorescent powder set was stored at room temperature in the same manner as the above white LED, and the EL spectrum change for 4 months was measured and shown in FIG. 11 .

After heat curing and storage at room temperature, the EL increased significantly for up to 1 month, and then showed a slight increase and then stabilized. The highest luminous efficiency measured at 20 mA and 2.55 V was 34.7 lm/W.

Therefore, it is judged that the white LED will be operated under the best conditions if used about one month after production. In addition, the luminous efficiency value (43.2 lm/W) of the white LED produced using the PS ^* and QS ^* fluorescent powder sets is the luminous efficiency value (34.7 lm/W) of the white LED produced using the SPS ^* and SQS ^* fluorescent powder sets. ), the stability evaluation for the applied current and driving time below was performed only for white LEDs manufactured using PS ^* and QS ^* fluorescent powder sets.

(2) Stability evaluation for applied current

In Example 4, the white LED manufactured using the green PS ^* and red QS ^* fluorescent powder set was connected to a total luminous flux measuring instrument (LEOS OPI 100) and an electroluminescence (EL) spectrum was obtained while applying a current from 10 mA to 100 mA. Luminous efficacy was measured. The EL spectrum is shown in FIG. 12, and when 10, 20, 40, 60, 80, and 100 mA were applied, the corresponding luminous efficiencies were 41.2, 40.1, 37.4, 34.8, 32.7, and 30.9 lm/W, respectively. It was confirmed that the manufactured white LED exhibited stable optical characteristics corresponding to the change in applied current.

(3) Stability evaluation for running time

In Example 4, the white LED manufactured by using the green PS ^* and red QS ^* fluorescent powder set was connected to a total luminous flux measuring device (LEOS OPI 100) and an electroluminescence (EL) spectrum and light efficiency while continuously flowing a current of 20 mA (luminous efficacy) was measured and shown in FIGS. 13a and 13b. A decrease in luminous efficiency at the beginning is a common phenomenon, and it stabilized after showing a slight decrease during continuous operation for 2 days, which is a very encouraging result. The decrease in luminous efficiency is, as seen in the EL spectrum, green PS ^* This is due to the decrease in the fluorescence of the fluorescent powder, and the stability of the fluorescent powder is partially reduced due to the heat generated when the LED is driven for a long time. Nevertheless, it is evaluated as the most stable among the examples reported to date. In Evaluation Example 1, the PS ^* and SPS ^* fluorescent films had very good stability to moisture or UV, but the thermal stability was slightly decreased and recovered considerably when left at room temperature, so it is expected that the white LED will also show similar characteristics.

As a result of the above evaluation, the fluorescent material to which the phenyl derivative of the present invention is bonded provides a fluorescent film and a light emitting device having significantly superior stability than the case of inorganic polymer particles including perovskite quantum dots reported so far.

In the above, a preferred embodiment according to the present invention has been described with reference to the drawings and examples, but this is merely an example, and various modifications and equivalent other embodiments are possible by those skilled in the art. will be able to understand Accordingly, the protection scope of the present invention should be defined by the appended claims.

P: perovskite quantum dots
Q: CdSe/ZnS core/shell quantum dots
S: Nanostructured hydrophobic silica particles
SP: Hybrid particles of nanostructured hydrophobic silica particles and perovskite quantum dots
SQ: Nanostructured hydrophobic silica particles and hybrid particles of CdSe/ZnS core/shell quantum dots
SPS: Silica Fluorescent Powder with SPs
SQS: Silica Fluorescent Powder with SQs
SPS ^* : Fluorescent powder in which a phenyl derivative is bound to the surface of silica containing SPs
SQS ^* : Fluorescent powder in which a phenyl derivative is bound to the surface of silica containing SQs
PS: Silica fluorescent powder directly containing Ps
QS: Silica Fluorescent Powder with Directly Embedded Qs
10: perovskite quantum dots
11: Hydrophobic silica base particles
20: Inorganic polymer matrix (silica, alumina, or a combination of both)
30: micropore network channel

Claims (22)

inorganic polymer matrix;
hydrophobic fluorescent nanoparticles embedded in the inorganic polymer matrix; and
a phenyl derivative bound to the surface of the inorganic polymer matrix;
Fluorescent material containing. According to claim 1,
The phenyl derivative bonded to the surface of the inorganic polymer matrix comprises a phenyl group connected by a hydrocarbon chain having 1 to 6 carbon atoms. According to claim 1,
The phenyl derivative is a fluorescent material comprising a compound represented by the following formula (1):
<Formula 1>
R ₁ Si(OR ₂ ) ₃
In the above formula, R ₁ is an alkyl group having 1-6 carbon atoms to which a phenyl group is bonded, and R ₂ is an alkyl group having 1-4 carbon atoms. The method of claim 1,
A fluorescent material in which the phenyl derivative bound to the surface of the inorganic polymer matrix blocks the micropore network channels present in the inorganic polymer matrix to protect the fluorescent nanoparticles, and the surface of the inorganic polymer matrix becomes hydrophobic. According to claim 1,
In the inorganic polymer matrix, the fluorescent material further comprising hydrophobic basal particles having a nano-pattern of a concave-convex structure on the surface. 6. The method of claim 5,
At least a portion of the hydrophobic fluorescent nanoparticles is disposed in a concave portion of the concave-convex structure of the surface of the base particle to form a hybrid particle. 7. The method of claim 6,
A first hydrophobic functional group or ligand is included on the surface of the basal particle, a second hydrophobic functional group or ligand is included on the surface of the fluorescent nanoparticle, and the first hydrophobic functional group or ligand on the surface of the basal particle and the surface of the fluorescent nanoparticle A fluorescent material in which a physical bond is formed between the second hydrophobic functional group or the hydrophobic ligand. 8. The method of claim 7,
The first hydrophobic functional group or ligand and the second hydrophobic functional group or ligand each independently include a hydrocarbon chain having 6 to 20 carbon atoms. 6. The method of claim 5,
The base particle is a fluorescent material comprising silica, alumina, or a combination thereof. 6. The method of claim 5,
A fluorescent material having an average particle diameter of the base particles of 50 nm to 200 nm. The method of claim 1,
The fluorescent nanoparticles include at least one selected from perovskite nanocrystals, semiconductor nanocrystals, inorganic phosphors, fluorescent dyes, and dye-doped transparent metal oxides. The method of claim 1,
A fluorescent material having an average particle diameter of the fluorescent nanoparticles of 3 nm to 15 nm. The method of claim 1,
The inorganic polymer matrix is a fluorescent material comprising silica, alumina, or a combination thereof. The method of claim 1,
A fluorescent material further comprising metal nanoparticles including at least one selected from Au, Ag, alloys thereof, or a combination thereof together with the fluorescent nanoparticles. According to claim 1,
A fluorescent material in which the fluorescent material is in the form of a powder. A fluorescent film comprising the fluorescent material according to any one of claims 1 to 15 and a polymer. A light emitting device comprising the fluorescent material according to any one of claims 1 to 15. 18. The method of claim 17,
The light emitting device is a light emitting device selected from the group consisting of a light emitting diode (light-emitting diode), a light emitting transistor (light-emitting transistor), a laser (laser), and a polarized (polarized) light emitting device. preparing a first solution by dispersing a first fluorescent powder including hydrophobic fluorescent nanoparticles embedded in an inorganic polymer matrix in an alcohol/toluene mixed solvent;
Preparing a second solution by adding and mixing a minimum amount of water and ammonia water necessary for the reaction to the first solution: And
sequentially adding an alkoxysilane precursor in which an alkoxysilane precursor and a phenyl derivative are bonded to the second solution at a time interval; and
reacting the mixed product;
The method of manufacturing a fluorescent material according to claim 1, comprising a. 20. The method of claim 19,
The method of manufacturing a fluorescent material, wherein the first solution further comprises hydrophobic base particles having a nanopattern having an uneven structure on the surface. 20. The method of claim 19,
Alkoxysilane is first added to the second solution, and after reaction for 2 to 5 minutes, alkoxysilane to which a phenyl derivative is added is added and reacted, whereby 1 to 2 nm-sized ultra-fine pore network channels in the inorganic polymer matrix are formed in the phenyl derivative. A method for producing a fluorescent material that is blocked by 20. The method of claim 19,
The method of manufacturing a fluorescent material further comprising vacuum drying and thermal drying the resultant obtained in the reaction step.

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