KR102515246B1 - A METHOD FOR PREPARING A NOVEL CsPbBr3/Glass COMPOSITE AND A CsPbBr3/Glass COMPOSITE PREPARED THEREBY - Google Patents

Abstract

The present invention relates to a method for preparing a novel CsPbBr ₃ /Glass composite and a CsPbBr ₃ /Glass composite prepared thereby, which is obtained by recrystallizing a precursor of CsPbBr ₃ from a glass frit capable of low-temperature sintering without using a solvent. The melt-quenching process can be simplified.
In addition, the CsPbBr ₃ /Glass composite prepared by the above preparation method may exhibit excellent green fluorescence characteristics and maximize water resistance by embedding CsPbBr ₃ in an organic matrix.

Description

Manufacturing method of novel CsPbBr3/Glass composite and CsPbBr3/Glass composite prepared thereby

The present invention relates to a method for preparing a novel CsPbBr ₃ /Glass composite and a CsPbBr ₃ /Glass composite prepared thereby. More specifically, a novel CsPbBr ₃ that can not only simplify the manufacturing process by recrystallizing the precursor of CsPbBr 3 in a glass frit capable of low-temperature sintering without using a solvent, but also exhibit excellent green fluorescence characteristics _and water resistance. /Glass composite manufacturing method and the CsPbBr ₃ /Glass composite prepared thereby.

Perovskite is a type of ceramic oxide. In 1839, German mineralogist Gustav Rosé discovered a rock sample in the Ural Mountains in central Russia, and its main component is calcium titanate (CaTiO) of perovskite. ₃ ) Because it is a compound, the above name was created. In crystallography, it is abbreviated as the ratio (1:1:3) of each compound in its molecular formula, and is also called the 113 structure. The general formula of the ideal perovskite structure is ABX ₃ , where A can be K ⁺ , Na ⁺ , Pb ²⁺ , Ba ²⁺ and more than 20 kinds of elements, B is Cr ³⁺ , Nb ⁵⁺ , It may be more than 50 kinds of elements such as Zr ⁴⁺ , and X may be composed of anions such as O, Cl, Br, I, and S. The central metal cation B and the anion X form a coordinated octahedral structure, and A exists in the gap of the octahedron to balance the charges of the BX ₃ anion.

Common organic-inorganic metal-halide perovskite materials have a chemical formula of ABX ₃ (A: organic or inorganic monovalent cation, B: divalent metal cation, X: Cl, Br and I) and have a high optical absorption coefficient ) and carrier mobility, and excellent optoelectronic properties such as long electron diffusion length and low exciton binding energy, so it is used in photovoltaic materials such as solar cells, photodetectors, humidity sensors, and It is receiving a lot of attention in the field of devices.

In addition, the narrow emission wavelength bandwidths and high quantum yields appearing in the bandgap structure of halide perovskite and the optoelectrical properties in which the bandgap is controlled according to the different composition ratios of halide anions are a light emitting device for display. is arousing interest in the study of

On the other hand, compared to the organic-inorganic hybrid type in which organic cations are substituted at the A-site, the inorganic perovskite material to which Cs ¹⁺ is applied is known to have particularly excellent thermal stability, but the external air of the metal-halide perovskite material However, due to low stability against humidity and light, there is a problem in that a serious deterioration phenomenon appears in its properties.

More specifically, inorganic perovskite materials are highly vulnerable to moisture and polar solvents due to the property of having interatomic ionic bonds, and thus have the characteristics of easy structural decomposition by ion migration.

Accordingly, in recent years, various studies have been conducted using ceramic materials as base materials to overcome the moisture and air vulnerabilities of metal-halide perovskite materials.

Specifically, a nanocomposite that can increase stability by using mesoporous silica and adsorbing CsPbX ₃ quantum dot (QD) to block anion exchange has been reported, and perovskite QD/ By synthesizing a silica nanocomposite, a method capable of greatly improving stability from air exposure has been disclosed.

On the other hand, research has been reported on minimizing the degradation of perovskite nanocrystals by moisture and air by directly embedding perovskite quantum dots (QDs) in a ceramic matrix using the melt-quenching method. Since CsPbBr ₃ quantum dot (QD) embedded in phosphate glass was first disclosed by the Zhao group in 2016, various systems in the form of CsPbX ₃ quantum dot (QD) composites based on glass matrix have been reported to improve stability and optical properties. .

Through the previously reported research results, it was easy to conclude that when CsPbX ₃ particles are embedded in a glass matrix, they exhibit better chemical stability and unique optical properties of metal-halide perovskite.

Based on previous studies, the present applicant recrystallizes CsBr and PbBr ₂ , which are precursors of CsPbBr ₃ , in a glass matrix without using any solvent to obtain a CsPbBr ₃ /Glass composite. By applying possible commercially available glass frits and CsPbBr ₃ precursors to the conventional phosphor in glass (PIG) sintering process, the rather complicated melt-quenching method, which has to go through a “melting-quenching-annealing-cooling process”, is simplified and green A method for manufacturing a CsPbBr3/glass composite capable of securing fluorescence characteristics and water resistance and a CsPbBr3/glass composite prepared through the manufacturing method have been invented.

KR 10-2020-0078290 A

An object of the present invention is to provide a method for preparing a novel CsPbBr ₃ /Glass composite and a CsPbBr ₃ /Glass composite prepared thereby.

Another object of the present invention is to prepare a novel CsPbBr ₃ /Glass composite that can simplify the existing complex melt-quenching method by recrystallizing the precursor of CsPbBr ₃ in a glass frit capable of low-temperature sintering without using a solvent. is to provide a way

Another object of the present invention is to provide a CsPbBr ₃ /Glass composite that can exhibit excellent green fluorescence characteristics and water resistance by being prepared by the method for preparing the novel CsPbBr ₃ /Glass composite.

In order to achieve the above object, a method for producing a CsPbBr ₃ /Glass composite according to an embodiment of the present invention includes 1) mixing and grinding glass frits, CsBr and PbBr ₂ in an alumina mortar to prepare a mixed powder; 2) pressurizing the mixed powder to prepare a powder molded body; and 3) a sintering step of sintering the powder compact.

The sintering step may be to slowly cool the powder molded body after maintaining it under conditions of 450 to 700 °C.

A CsPbBr ₃ /Glass composite according to another embodiment of the present invention is prepared by the above manufacturing method.

The CsPbBr ₃ /Glass composite has excellent green fluorescence characteristics and water resistance.

The CsPbBr ₃ /Glass composite may show a peak in the range of 500 to 550 nm when measuring a photoluminescence spectrum.

The CsPbBr ₃ /Glass complex may exhibit a full width at half maximum (FWHM) of 15 to 25 nm.

A light emitting device according to another embodiment of the present invention may include the CsPbBr ₃ /Glass composite.

Hereinafter, the present invention will be described in more detail.

A method for producing a CsPbBr ₃ /Glass composite according to an embodiment of the present invention includes: 1) preparing a mixed powder of mixing and grinding glass frits, CsBr and PbBr ₂ in an alumina mortar; 2) pressurizing the mixed powder to prepare a powder molded body; and 3) a sintering step of sintering the powder compact.

The CsBr and PbBr ₂ are precursors of CsPbBr ₃ , and are added at a molar ratio of 1:1 to allow recrystallization of the CsBr and PbBr ₂ powder by a solid-solution mechanism in the glass frit, which is a glass matrix. ) can be

Meanwhile, a conventional ceramic composite in which CsPbBr ₃ nanocrystals are embedded is obtained through a melting-quenching process having three main heat treatment routes.

Specifically, the glass matrix and the perovskite precursor mixture powder, which are base materials, are melted at a high temperature of 1000 ° C. or higher, followed by casting, and then an annealing process to relieve residual thermal stress is performed, thereby forming perovskite crystals are precipitated Thereafter, a process of preparing a perovskite/ceramic composite through heat treatment at 420 to 460 °C for about 10 hours was required.

However, the melting-quenching process had a problem of having to go through the melting-quenching-annealing-cooling process, so in the present invention, not only can the melting-quenching process be simplified, but also green fluorescence characteristics and water resistance A method for preparing this excellent CsPbBr ₃ /Glass composite was developed.

Specifically, the manufacturing method of the CsPbBr ₃ /Glass composite includes 1) mixing glass frits, CsBr and PbBr ₂ , which are precursors of CsPbBr ₃ , in an alumina mortar and grinding for 15 to 20 minutes; 2) pressurizing the mixed powder to prepare a powder molded body; and 3) a sintering step of sintering the powder compact.

Meanwhile, CsBr and PbBr ₂ , precursors of the CsPbBr ₃ , may be aggregated with each other during the recrystallization process to form a bulk CsPbBr ₃ structure. In this case, the metal-halide is formed by the low exciton binding energy of the perovskite material. There is a problem that it is difficult to express the unique optical properties of perovskite.

Accordingly, preferably, in the present invention, in order to suppress aggregation of CsPbBr ₃ embedded in the glass frits used as a glass matrix, ceramic powder particles as an additive may be added.

The ceramic powder particles added as the additive serve as a dispersion medium for CsPbBr ₃ , and may be selected from the group consisting of aluminum oxide (Al ₂ O ₃ ), silicon dioxide (SiO ₂ ), fumed silica, and mixtures thereof. Preferably, the ceramic powder particles may be fumed silica.

The aluminum oxide (Al ₂ O ₃ ) is a compound of oxygen and aluminum and is also called Illumina. It has a molecular weight of 101.94 and a melting point of 2090 °C. It is a hard, colorless crystalline powder with a high melting point and is used as a raw material for making aluminum. Corundum is pure alumina from nature, and ruby and sapphire are alumina with red and blue colors due to impurities. On the other hand, the aluminum oxide (Al ₂ O ₃ ) is also calculated as a main component of bauxite. It is insoluble in water and is an amphoteric oxide, but is also insoluble in acid when strongly degraded. The aluminum oxide (Al ₂ O ₃ ) has various uses, and specifically, it can be used in catalysts, catalyst carriers, and abrasives, as well as used in IC packages, ceramic wiring boards, and the like.

The silicon dioxide (SiO ₂ ) is a silicon oxide, also called silicic acid anhydride, and can be easily found in quartz or various living organisms. Silicon dioxide is one of the most abundant materials worldwide as a major component of sand. It can be made and used in the form of fused quartz, silica gel and airgel, and is widely used in structural materials, electrical insulators, food and pharmaceutical industries.

On the other hand, inhaling finely pulverized crystalline silicon dioxide is harmful to the human body and can cause silicosis, bronchitis, lung cancer, rheumatoid arthritis, etc. accompanied by severe inflammation. In addition, amorphous silicon dioxide also causes inflammation when ingested in high concentrations. In the case of silicon dioxide, the main component of sand, 95% is used not only in the construction industry, such as in concrete production, but also in the casting of metal parts that can be used in engineering devices and other applications due to its very high melting point.

The fumed silica is a fine particle that has a very large surface area and high purity, and tends to form chains in a chemical manufacturing process. It is prepared by injecting chlorosilanes into a flame of oxygen and hydrogen above 1000 °C. The chlorosilane as a raw material may be synthesized through a reaction between metallurgical silicon obtained by reducing mineral silicon dioxide (SiO ₂ ) with coke and hydrogen chloride.

On the other hand, the fumed silica powder is used for laminating and gel coat applications, and is used as a drying agent like silica gel. It is also used in cosmetics for its light diffusing properties, and is also used as a light abrasive in products such as toothpaste. Furthermore, it is used to adjust the viscosity of fillers of silicone elastomers and paints, coatings, printing inks, adhesives, cosmetics, sealants, toiletries, foods, beverages and unsaturated polyester resins.

Preferably, the method for preparing the CsPbBr ₃ /Glass composite includes: 1) a first mixed powder preparation step of mixing glass frits, CsBr, and PbBr ₂ in an alumina mortar and grinding for 15 to 20 minutes; 2) preparing a second mixed powder by adding fumed silica to the first mixed powder and grinding for 10 to 15 minutes; 3) pressurizing the second mixed powder to prepare a molded body; and 4) a sintering step of sintering the powder compact.

That is, in the manufacturing process, by adding the additive, CsBr and PbBr ₂ are prevented from aggregating with each other to form a bulk structure in the recrystallization process, thereby improving the optical properties unique to metal-halide perovskite There are advantages.

More preferably, the glass frit, precursor (CsBr+PbBr ₂ ) and ceramic powder particles included in the manufacturing method of the CsPbBr ₃ /Glass composite are 3 to 6 parts by weight of the precursor and ceramic powder particles 3 based on 100 parts by weight of the glass frit. to 12 parts by weight.

In the case of the above weight range, there is an advantage of exhibiting excellent green fluorescence characteristics or excellent water resistance according to the mixing of the components.

However, if it is less than the above weight range, there is a problem in that the green fluorescence property is insignificant, and if it exceeds the above weight range, excessive CsPbBr ₃ aggregates to form a bulk state, resulting in insignificant green fluorescence property and poor sintering completeness. there is

The sintering step may be to slowly cool the powder molded body after maintaining it under conditions of 450 to 700 °C.

The above salpin melt-quenching process goes through three main heat treatment routes, including heat treatment under high temperature conditions of 1000 ° C or higher. Accordingly, the present invention not only has the advantage of simplifying the existing complex melt-quenching process through the manufacturing method of the CsPbBr ₃ /Glass composite, but also uses a glass frit capable of low-temperature sintering without using a solvent at low temperature conditions. It has the advantage of being able to manufacture a CsPbBr ₃ /Glass composite with high sintering perfection.

Therefore, the sintering step may be to put the powder compact in an electric furnace and maintain it within 1 hour at 450 to 700 ° C., and then slowly cool it, more preferably, slowly cool it after maintaining it at 650 ° C. for 10 minutes. it could be

The CsPbBr ₃ /Glass composite according to another embodiment of the present invention is prepared by the above manufacturing method,

The CsPbBr ₃ /Glass composite has excellent green fluorescence characteristics and water resistance.

The CsPbBr ₃ , which is one of the inorganic perovskites, exhibits a high light absorption coefficient and carrier mobility, has a long electron diffusion lenth, and has a low exciton binding energy (exiton binding energy) and has excellent optoelectronic properties.

Accordingly, CsPbBr ₃ is utilized in fields such as solar cells, diodes, photodetectors, and photoelectric materials by utilizing the excellent optoelectronic and fluorescent properties.

However, the inorganic perovskite CsPbBr ₃ exhibits unique ionicity, and thus has poor water resistance, and thus has a low possibility of utilization in all fields where water exists.

To overcome this, water resistance is improved by using zwitterions, organic and inorganic hybrid ion pairs, organic Lewis bases such as thiophene and pyridine, and metal oxides such as SiO ₂ , Al ₂ O ₃ , and Ta ₂ O ₅ Research has been conducted to do this, but the effect is insignificant.

Accordingly, the present invention has the advantage of not only improving green fluorescence characteristics by embedding CsPbBr ₃ in a glass matrix through the manufacturing method of the CsPbBr ₃ /Glass composite, but also manufacturing a CsPbBr ₃ /Glass composite with improved water resistance. there is.

The CsPbBr ₃ /Glass composite may show a peak in the range of 500 to 550 nm when measuring a photoluminescence spectrum.

Luminescence is a phenomenon in which a specific material emits light of a wavelength corresponding to an energy difference between them while falling from an unstable state of high energy to a stable state of low energy. Therefore, in order to emit such light, it is necessary to make a specific material into an unstable excited state with high energy. For this, various methods such as light, chemical reaction, electricity, heat, or electrons from a cathode can be used. Therefore, depending on the method of creating an excited state, emission is classified by adding photo-, chemical (chemi-), heat (thermo-), electricity (electro-), and cathode (cathodo-) in front of light emission.

More specifically, photoluminescence includes fluorescence and phosphorescence. Fluorescence is when light is emitted while returning to a lower energy state from an initially excited state, and light is emitted when converted to a lower energy state after being converted to another excited state. It is phosphorescent.

The CsPbBr ₃ /Glass complex may exhibit excellent fluorescence characteristics, and more specifically, may exhibit green fluorescence characteristics.

Accordingly, the green fluorescence characteristic may be measured using photoluminescence spectroscopy, and may exhibit a peak in the range of 500 to 550 nm when measured by the spectroscopy method. That is, it can be confirmed that the green fluorescence characteristic exists by confirming that a peak is displayed in the wavelength range of the visible ray region.

The CsPbBr ₃ /Glass complex may exhibit a full width at half maximum (FWHM) of 15 to 25 nm.

The full width at half maximum (FWHM) is also referred to as the full width at half maximum, and may mean a wavelength width corresponding to 1/2 of the maximum value of a curve representing a wavelength. A narrow half-width means that a range of colors that can be implemented is wide, which may mean that colors closer to natural colors can be implemented.

Quantum dots, which are known as conventional light emitting materials in the visible ray region, are known to have a half width of about 30 to 55 nm, but the CsPbBr ₃ /Glass composite of the present invention is characterized by a narrow half width of 15 to 20 nm, through which It has the advantage of being able to show a better color gamut.

Furthermore, the CsPbBr ₃ /Glass composite of the present invention may exhibit excellent photoluminescence quantum yield (PLQY).

The CsPbBr3/Glass complex may be included in a light emitting device, etc., and the photoluminescence quantum yield (PLQY) is a physical property directly related to the light emitting ability of a dopant included in a light emitting layer in a light emitting device. That is, if the light emitting quantum yield (PLQY) of the dopant included in the light emitting layer is low, the light emitting efficiency of the light emitting device is lowered, so that the light emitting device has to be driven under a high current to obtain a predetermined luminance. It may cause a decrease in life span.

Accordingly, the CsPbBr ₃ /Glass composite exhibits an excellent photoluminescence quantum yield (PLQY), thereby having an advantage of solving the problem of reducing the lifetime of a light emitting device including the CsPbBr ₃ /Glass composite.

More specifically, the photoluminescence quantum yield (PLQY) of the CsPbBr ₃ /Glass composite may represent a measured value of 10 to 20%.

A light emitting device according to another embodiment of the present invention may include the CsPbBr ₃ /Glass composite.

By including the CsPbBr ₃ /Glass complex in the light emitting device, the light emitting device can exhibit excellent green fluorescence characteristics and water resistance, and can exhibit excellent color gamut due to a narrow half width.

More specifically, the light emitting device may be selected from the group consisting of a light-emitting diode, a light-emitting transistor, a laser, and a polarized light emitting device, but is not limited thereto.

According to the manufacturing method of the novel CsPbBr ₃ /Glass composite of the present invention and the CsPbBr ₃ /Glass composite prepared thereby, the precursor of CsPbBr ₃ is recrystallized in a glass frit capable of low-temperature sintering without using a solvent. It has the effect of simplifying the complicated melt-quenching process.

Meanwhile, the CsPbBr ₃ /Glass composite prepared by the above manufacturing method not only exhibits excellent green fluorescence characteristics, but also has an effect of maximizing water resistance by embedding CsPbBr ₃ in an organic matrix.

1 shows a method for preparing a CsPbBr ₃ /Glass composite according to an embodiment of the present invention.
2 is an experimental result of verifying a sintering temperature condition of a glass frit according to an embodiment of the present invention.
3 is an experimental result showing the fluorescence characteristics of the CsPbBr ₃ /Glass composite according to an embodiment of the present invention through fluorescence images.
4 is a measurement result of a light emission spectrum (PL spectra) of a CsPbBr ₃ /Glass composite according to an embodiment of the present invention.
5 is a CsPbBr ₃ particle analysis test result of a CsPbBr ₃ /Glass composite according to an embodiment of the present invention.
6 is a water resistance test result of a CsPbBr ₃ /Glass composite according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail so that those skilled in the art can easily implement the present invention. However, the present invention may be embodied in many different forms and is not limited to the embodiments set forth herein.

Verification of materials and sintering temperature conditions

Cesium(I) bromide (CsBr, 99.9%) was purchased from Alfa Aesar, lead(II) bromide (PbBr ₂ , 99%) was purchased from Kojundo korea, and fumed silica (aggregated particle size: 0.2 to 0.3 μm) was purchased from Sigma Aldrich and used. Meanwhile, a Zn-B-Al-Si-based glass frit was purchased from Ferro (product code: EG 3046) and used.

In order to determine the sintering temperature conditions of the glass frit used as the base material, an experiment was performed under each condition shown in FIG. 2 to determine the optimal sintering temperature and holding time. Specifically, the sintering temperature was 650 ° C., The holding time was determined to be 10 minutes.

manufacturing example

1) After fixing CsBr and PbBr ₂ in a molar ratio of 1:1 to a glass frit (GF) and adding them, grinding in an alumina mortar for 20 minutes to prepare a mixed powder (first mixed powder), 2) A powder compact was obtained by pressing with a press (1t) equipment using a stainless mold having a size of 17 Φ. 3) Finally, the powder compact was put into an electric furnace (Hantech C-22p), maintained at 650 ° C for 10 minutes, and then subjected to a sintering step of slow cooling to prepare a CsPbBr ₃ /Glass composite (T1).

On the other hand, after step 1), 2) fumed silica was added to the prepared mixed powder (first mixed powder) and ground for 10 minutes to prepare a mixed powder (second mixed powder), 3) The second mixed powder was pressed with a press (1t) equipment using a stainless mold having a size of 17 Φ to obtain a compacted powder. 4) Finally, the powder compact was placed in an electric furnace (Hantech C-22p), maintained at 650 ° C for 10 minutes, and then subjected to a sintering step of slow cooling to prepare a CsPbBr ₃ /Glass composite (T2 to T6).

The weight ranges of glass frit, precursor (CsBr+PbBr ₂ ) and fumed silica (FS), which are materials used in the manufacturing process of the CsPbBr ₃ /Glass composite, are shown in Table 1 below.

T1 T2 T3 T4 T5 T6 Glass Frit (GF) 100 100 100 100 100 100 Precursor (CsBr+PbBr ₂ ) 6 1.5 3 4.5 6 7.5 Fumed Silica (FS) - 1.5 3 7.5 12 13.5

(unit: parts by weight)

Experimental example

1. Fluorescence characterization experiment

The optical properties of the CsPbBr ₃ /Glass composite prepared according to the above Preparation Example were measured by photoluminescence (PL), Full width at half maximum (FWHM) and photoluminescence quantum yield (PLQY) were evaluated.

1-1. Fluorescence image verification experiment

First, the emission characteristics of the T1 to T6 samples in the state of irradiation with the ultraviolet rays could be observed with the naked eye through the fluorescence images of the samples, and the results are shown in FIG. 3 .

Specifically, FIG. 3(a) shows a fluorescence image of the T1 sample. As the excess CsPbBr ₃ aggregates with each other to form a bulk structure, weak fluorescence with colors of various wavelengths is observed throughout the sample. can confirm that it is.

Meanwhile, FIG. 3(b) shows a fluorescence image of the T2 sample, and it can be seen that green fluorescence is observed only in a localized portion of the sample by adding a very small amount of the precursor.

3(c) to 3(e) show fluorescence images for the T3 to T5 samples, respectively, and it can be seen that not only the sintering completeness is high, but also the green fluorescence characteristics are excellent, especially in the case of the T5 In the case of , it can be seen that the effect is maximized.

3(f) shows a fluorescence image of the T6 sample, and it can be confirmed that some green fluorescence characteristics appear, but there is a problem of poor sintering completeness.

1-2. Photoluminescence spectrum (PL spectra) experiment

Meanwhile, the PL spectra measurement results for the T4 and T5 samples exhibiting excellent sintering completeness and green fluorescence characteristics are shown in FIG. 4 .

According to FIG. 4, it can be seen that a peak appears at 515 nm for the T4 sample, and a peak appears at 519 nm for the T5 sample.

In the case of full width at half maximum (FWHM) and photoluminescence quantum yield (PLQY), the full width at half maximum (FWHM) and photoluminescence quantum yield (PLQY) of the T4 sample were measured to be 17 nm and 10.3%, respectively, and the T5 sample had a full width at half maximum (FWHM) and photoluminescence quantum yield (PLQY) of The luminescence quantum yield (PLQY) was measured as 17 nm and 17.7%, respectively.

Through this, in the case of the CsPbBr ₃ /Glass composite of the present invention, it can be confirmed that the light emitting property is excellent, and it can be seen that the color purity is excellent because it exhibits a narrow half width.

2. CsPbBr embedded in glass matrix ₃ particle analysis experiment

CsPbBr ₃ particles embedded in the glass matrix were identified through SEM (Hitachi SU-70) and EDS mapping analysis.

Specifically, the cross-sectional microstructure of the T5 sample was shown through SEM images and EDS qualitative analysis, and in order to more clearly identify CsPbBr ₃ particles having a relatively high electron density, a back-scattered electrons (BSE) detector was used. image was observed. The result is shown in FIG. 5 .

According to FIG. 5 (a), it was observed that CsPbBr ₃ particles having a size of about 1 to 3 μm were embedded in a glass matrix with almost no pinholes, and further, by FIG. 5 (b), Cs, Pb , Br elements and Si, the main element forming the glass frit, were subjected to qualitative analysis through EDS mapping, confirming that the CsPbBr ₃ particles were clear.

3. Water resistance test

In order to verify the water resistance performance, the CsPbBr ₃ /Glass composite sample (T5) was completely immersed in water for 4 days, and the photoluminescence quantum yield (PLQY) measurement value and UV (365 nm) were irradiated. Fluorescence images were monitored over time The results are shown in FIG. 6 .

Meanwhile, the images inserted in FIG. 6 show the state in which the CsPbBr ₃ /Glass composite sample (T5) completely submerged in water is exposed to incandescent light and ultraviolet light, respectively.

According to FIG. 6, even when the sample is completely submerged in water, a green fluorescence image emitted by being excited by ultraviolet rays can be confirmed, and each measured value of the photoluminescence quantum yield (PLQY) is ±1.1pp (percentage point) or less compared to the initial value. It was confirmed that the PLQY change rate of Through this, it can be seen that the CsPbBr ₃ /Glass composite sample of the present invention has excellent water resistance.

Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concept of the present invention defined in the following claims are also made according to the present invention. falls within the scope of the rights of

Claims (7)

1) Mixed powder manufacturing step of mixing and grinding glass frits, CsBr and PbBr ₂ in an alumina mortar;
2) pressurizing the mixed powder to prepare a powder molded body; and
3) comprising a sintering step of sintering the powder compact
Manufacturing method of CsPbBr ₃ /Glass composite. According to claim 1,
The sintering step is to slowly cool the powder compact after maintaining it under conditions of 450 to 700 ° C.
Manufacturing method of CsPbBr ₃ /Glass composite. delete delete delete delete delete

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