A method for preparing a CsPbBr X I 3-X Method for producing quantum dot microcrystalline glass material

Abstract

The present invention discloses a method for preparing CsPbBr X I 3‑X The method for preparing quantum dot microcrystalline glass material comprises the following steps: (1) weighing raw materials according to glass formula, mixing and grinding them uniformly; (2) preparing CsPbBr X I 3‑X Crude quantum dot glass-ceramics; (3) the prepared CsPbBr X I 3‑X The crude quantum dot glass-ceramics was placed in a Na2CO3 solution for magnetic stirring and ultrasonic cleaning to obtain CsPbBr after Na2CO3 cleaning. X I 3‑X Quantum dot glass-ceramics; (4) CsPbBr after cleaning with Na2CO3 X I 3‑X The quantum dot glass-ceramics was placed in a crystallization furnace for crystallization and cooled to obtain CsPbBr X I 3‑X Quantum dot glass-ceramic material. The present invention significantly improves the CsPbBr by using Na2CO3 cleaning-heat treatment strategy. X I 3‑X Luminous efficiency and stability of quantum dot glass-ceramics.

Description

Technical Field

[0001] The present invention belongs to the field of quantum dot glass-ceramics, and specifically relates to a method for preparing CsPbBr X I 3-X Methods for perovskite quantum dot glass-ceramics materials. Background Art

[0002] White light-emitting diodes (LEDs) have the advantages of high efficiency, long life, low power consumption, environmental protection, and rich colors. They are widely used in automotive lighting, medical equipment, biotechnology, agricultural lighting and other fields. However, current commercial LEDs still have shortcomings such as low light energy conversion efficiency, poor color stability, and short life. There is an urgent need to design a luminescent material with high luminous efficiency and high stability.

[0003] All-inorganic perovskite quantum dots (PQDs) offer advantages such as high luminous efficiency, ease of preparation, and high color purity, making them a promising next-generation display material. However, PQDs still have limitations. They are sensitive to water, heat, light, and oxygen, resulting in poor stability and limiting their further commercial development. Summary of the Invention

[0004] The purpose of the present invention is to overcome the shortcomings and deficiencies of the prior art and to provide a new Na2CO3 cleaning-heat treatment strategy for the preparation of CsPbBr X I 3-X A method for preparing quantum dot microcrystalline glass materials to improve the luminous efficiency and stability of the quantum dot microcrystalline glass materials.

[0005] The technical solutions adopted by the present invention are as follows:

[0006] A method for preparing CsPbBr X I 3-X Quantum dot glass-ceramic material method, the CsPbBr X I 3-X , X=0-3, the method comprises the following steps:

[0007] (1) According to CsPbBr X I 3-X Glass formula of quantum dot glass-ceramic material: weigh the raw materials, mix and grind them evenly;

[0008] (2) The mixed raw materials are quenched by melt water to obtain precursor glass powder, or the precursor glass powder is obtained by melt casting and then grinding; the precursor glass powder is then placed in a crystallization furnace for heat treatment and crystallization, and naturally cooled to room temperature to obtain CsPbBr X I 3-X Crude quantum dot glass-ceramics;

[0009] (3) The prepared CsPbBr X I 3-X The crude quantum dot glass-ceramics is placed in a Na2CO3 solution with a concentration of 1-50 g / 50 ml for magnetic stirring and ultrasonic cleaning to obtain the CsPbBr X I 3-X quantum dot glass-ceramics; wherein the CsPbBr X I 3-X The feeding ratio of the crude quantum dot glass-ceramics and the Na2CO3 solution with a concentration of 1-50 g / 50 ml is CsPbBr X I 3-X The mass ratio of the crude quantum dot glass-ceramics and the Na2CO3 is 20-60%:80-40%;

[0010] (4) The CsPbBr X I 3-X The quantum dot glass-ceramics is placed in a crystallization furnace and heated to 450-600℃ for 1-10 h to obtain the CsPbBr X I 3-X quantum dot glass-ceramics material.

[0011] In the specific embodiments of the present application, the CsPbBr X I 3-X The base glass of the quantum dot glass-ceramics material is a B-Si-Zn glass system. Other silicate glass systems are also applicable, such as a Li-Al-Si glass system. The melt water quenching method in step (2) refers to high-temperature melting of the mixed and uniform raw materials followed by water quenching and drying to obtain the precursor glass powder. As a preferred, the high-temperature melting condition in the melt water quenching method or melt casting is: heating to 1000-1700℃, and maintaining for 5-20 minutes.

[0012] As a preferred, the CsPbBr X I 3-XThe base glass of the quantum dot microcrystal glass material is a B-Si-Zn glass system, and the glass formula is composed of the following components with the following contents, wherein the raw material content is expressed in terms of molar percentage content: B2O315-40%, SiO220-50%, ZnO 0-15%, K2CO31-5%, Al2O30-10%, Cs2CO32-10%, PbBr20-10%, PbI20-10%, NaBr 0-15%, NaI 0-9%, wherein the content of PbBr2and NaBr is not 0 or the content of PbI2and NaI is not 0. It is further preferred that the glass formula is composed of the following components with the following contents, wherein the raw material content is expressed in terms of molar percentage content: B2O320-30%, SiO220-30%, ZnO 10-15%, K2CO31-5%, Al2O35-10%, Cs2CO35-10%, PbBr2+PbI22-7%, NaBr+NaI 8-13%. Since the preparation of CsPbBr X I 3-X quantum dots, therefore those skilled in the art can understand that when designing the proportion of raw materials, the molar ratio of PbBr2to PbI2and the molar ratio of NaBr to NaI should be close to x / (x-3). In the specific embodiment of the present application, X=3, then the glass formula is composed of the following components with the following contents, wherein the raw material content is expressed in terms of molar percentage content: B2O310-30%, SiO220-30%, ZnO 10-15%, K2CO31-5%, Al2O35-10%, Cs2CO35-10%, PbBr22-7%, NaBr 8-13%.

[0013] As a preferred, the CsPbBr X I 3-XThe base glass of the quantum dot glass-ceramic material is a Li-Al-Si glass system, and the glass formula is composed of the following components with the following contents, wherein the raw material content is expressed in terms of molar percentage: SiO2 20-30%, B2O3 10-20%, Li2CO3 10-20%, K2CO3 1-5%, Al2O3 1-5%, Cs2CO3 5-15%, PbBr2 0-15%, PbI2 0-15%, NaBr 0-10%, and NaI 0-10%, wherein the content of PbBr2 and NaBr is not 0 or the content of PbI2 and NaI is not 0. As a further preferred, the glass formula is composed of the following components with the following contents, wherein the raw material content is expressed in terms of molar percentage: SiO2 20-30%, B2O3 10-20%, Li2CO3 10-20%, K2CO3 1-5%, Al2O3 1-5%, Cs2CO3 5-15%, PbBr2+PbI2 10-20%, NaBr+NaI 5-15%. Since the preparation of CsPbBr X I 3-X Quantum dots, therefore, those skilled in the art can understand that when designing the proportion of raw materials, the molar ratio of PbBr2 to PbI2 and the molar ratio of NaBr to NaI should be close to x / (x-3).

[0014] As preferred, in step (1), the heat treatment crystallization conditions are: heating to 450-600°C for 4-12h.

[0015] As preferred, in step (2), the drying conditions are: drying in an oven at 40-70°C for 2-24h.

[0016] As preferred, in step (3), the magnetic stirring speed is 500-3000r / min, the stirring time is 10-50min, and the ultrasonic cleaning time is 10-50min.

[0017] As preferred, in step (3), the CsPbBr X I 3-X The feeding ratio of the quantum dot glass-ceramic crude product and the Na2CO3 solution with a mass concentration of 1-50g / 50ml is CsPbBr X I 3-X The mass ratio of the quantum dot glass-ceramic crude product and Na2CO3 is 20-40%:80-60%, and more preferably 30-20%:70-80%.

[0018] As preferred, in step (4), the temperature is raised to 480-550°C, and more preferably 500-550°C, and the holding time is 2-7h.

[0019] Compared with the prior art, the present application has the beneficial effect that the present application significantly improves the CsPbBr X I 3-X The luminescent efficiency and stability of the quantum dot microcrystal glass. BRIEF DESCRIPTION OF DRAWINGS

[0020] The drawings of the present application are used to further explain the present application. Other drawings obtained based on the following drawings still belong to the scope of the present application without paying creative labor.

[0021] Figure 1 Glass body fluorescence graph of CsPbBr3 quantum dots prepared for Examples 1-4 (365nm excitation, slit width 2.5);

[0022] Figure 2 Aging stability test graph of CsPbBr3 quantum dot glass body prepared for Examples 1-4.

[0023] Figure 3 Glass body fluorescence graph of CsPbBr1I2 quantum dots prepared for Examples 5-6 (460nm excitation, slit width 2.5)

[0024] Figure 4 Aging stability test graph of CsPbBr1I2 quantum dot glass body prepared for Examples 5-6. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical scheme and advantages of the present application more clear, the present application will be further described in detail below with reference to the drawings.

[0026] Examples 1-4

[0027] The amount of each raw material substance shown in Table 1 was weighed. Mixing and grinding were performed for 30 min, the platinum crucible was loaded, placed in a high-temperature electromagnetic oven, heated to 1200℃, and after 5 min of heat preservation, water quenching was performed, and drying was performed in a 60℃ oven for 10 h. After drying, it was placed in a crystallization furnace at 550℃ for 5 h. Then, natural cooling was performed to room temperature, the glass was taken out, and CsPbBr3 quantum dot glass was obtained, and then according to the addition amount of Table 1, it was placed in 50mL of Na2CO3 solution with different mass concentrations for magnetic stirring for 10 min (stirring speed 900r / min) and ultrasonic cleaning for 10 min. Finally, it was placed in a crystallization furnace and heated to 520℃ for 6 h. The finished product was tested for related performance, among which the aging test was to place the sample in an aging box with 60℃, 90% humidity, and blue light 5000nit irradiation, and measure the fluorescence intensity of the sample after being placed for different time. The test results are as follows Figure 1 and Figure 2The luminescence intensity and stability are increased compared with the sample without Na2CO3 cleaning-heat treatment, and the performance is best when the concentration of Na2CO3 solution is 3 g / 50 ml.

[0028] Table 1

[0029]

[0030] Table 2

[0031]

[0032]

[0033] Examples 5-6

[0034] The amounts of each raw material substance shown in Table 3 were weighed. Mixing and grinding were performed for 30 min, the mixture was loaded into a platinum crucible, placed in a high-temperature electromagnetic furnace, and heated to 1200°C, and then water-quenched after 5 min of heat preservation, and placed in a 60°C oven for drying for 10 h. After drying, it was placed in a crystallization furnace at 500°C for 10 h. Then, it was naturally cooled to room temperature, the glass was taken out, and a CsPbBrI2 quantum dot glass was obtained, and then it was placed in an 8 g / 50 mL mass concentration Na2CO3 solution according to the amount shown in Table 4 for magnetic stirring for 10 min (stirring speed 900 r / min) and ultrasonic cleaning for 10 min. Finally, it was placed in a crystallization furnace and heated to 500°C for 2 h. The finished product was tested for relevant performance, and the aging test was performed by placing the sample in an aging box with 60°C, 90% humidity, and blue light 5000 nit irradiation, and measuring the fluorescence intensity of the sample after different time periods. The test results are shown in Figure 3 and Figure 4 The luminescence intensity and stability are increased compared with the sample without Na2CO3 cleaning-heat treatment.

[0035] Table 3

[0036]

[0037] Table 4

[0038]

[0039] The above disclosure is only the preferred embodiments of the present application, and of course cannot limit the scope of the rights of the present application, so the equivalent changes made according to the claims of the present application are still within the scope covered by the present application.

Claims

1. Preparation of CsPbBr X I 3-X Quantum dot glass-ceramic material method, the CsPbBr X I 3-X wherein X=0-3, characterized in that: The method comprises the following steps: (1) According to CsPbBr X I 3-X Glass formula of quantum dot glass-ceramic material: weigh the raw materials, mix and grind them evenly; (2) The mixed raw materials are quenched by melt water to obtain precursor glass powder, or the precursor glass powder is obtained by melt casting and then grinding; the precursor glass powder is then placed in a crystallization furnace for heat treatment and crystallization, and naturally cooled to room temperature to obtain CsPbBr X I 3-X Crude quantum dot glass-ceramics; (3) Prepared CsPbBr X I 3-X The crude quantum dot glass-ceramics was placed in a Na2CO3 solution with a concentration of 1-50 g / 50 ml and subjected to magnetic stirring and ultrasonic cleaning to obtain CsPbBr after Na2CO3 cleaning. X I 3-X Quantum dot glass-ceramics; among them CsPbBr X I 3-X The feed ratio of the crude quantum dot glass-ceramics to the Na2CO3 solution with a concentration of 1-50g / 50ml is CsPbBr X I 3-X The mass ratio of the crude quantum dot glass-ceramics to Na2CO3 is 20-60%:80-40%; (4) CsPbBr after Na2CO3 cleaning X I 3-X The quantum dot glass-ceramics is placed in a crystallization furnace, heated to 450-600℃ and kept for 1-10h, and then cooled to obtain CsPbBr X I 3-X Quantum dot glass-ceramic material.

2. The method according to claim 1, wherein: In step (3), CsPbBr X I 3-X The feeding ratio of the crude quantum dot glass-ceramics and the Na2CO3 solution with a mass concentration of 1-50g / 50ml is CsPbBr X I 3-X The mass ratio of the crude quantum dot glass-ceramics to Na2CO3 is 20-40%:80-60%.

3. The method according to claim 1, wherein: In step (3), CsPbBr X I 3-X The feeding ratio of the crude quantum dot glass-ceramics and the Na2CO3 solution with a mass concentration of 1-50g / 50ml is CsPbBr X I 3-X The mass ratio of the crude quantum dot glass-ceramics to Na2CO3 is 30-20%:70-80%.

4. The method according to any one of claims 1 to 3, characterized in that: The CsPbBr X I 3-X The base glass of the quantum dot microcrystalline glass material is a B-Si-Zn glass system, and the glass formula is composed of components with the following contents, wherein the raw material contents are expressed in molar percentage: B2O3 15-40%, SiO2 20-50%, ZnO 0-15%, K2CO3 1-5%, Al2O3 0-10%, Cs2CO3 2-10%, PbBr2 0-10%, PbI2 0-10%, NaBr 0-15%, NaI 0-9%, wherein the contents of PbBr2 and NaBr are not 0 or the contents of PbI2 and NaI are not 0.

5. The method according to claim 4, wherein: The glass formula is composed of the following components, where the raw material contents are expressed in molar percentage: B2O3 20-30%, SiO2 20-30%, ZnO 10-15%, K2CO3 1-5%, Al2O3 5-10%, Cs2CO3 5-10%, PbBr2+PbI2 2-7%, and NaBr+NaI 8-13%.

6. The method according to claim 5, wherein: If X=3, the glass formula is composed of the following components, where the raw material contents are expressed in molar percentage: B2O3 20-30%, SiO2 20-30%, ZnO 10-15%, K2CO3 1-5%, Al2O3 5-10%, Cs2CO3 5-10%, PbBr2 2-7%, and NaBr 8-13%.

7. The method according to claim 1, wherein: The CsPbBr X I 3-X The base glass of the quantum dot microcrystalline glass material is a Li-Al-Si glass system, and the glass formula is composed of the following components, wherein the raw material content is expressed in molar percentage: SiO2 20-30%, B2O3 10-20%, Li2CO3 10-20%, K2CO3 1-5%, Al2O3 1-5%, Cs2CO35-15%, PbBr2 0-15%, PbI2 0-15%, NaBr 0-10%, NaI 0-10%, wherein the content of PbBr2 and NaBr is not 0 or the content of PbI2 and NaI is not 0.

8. The method according to claim 7, wherein: The glass formula is composed of the following components, where the raw material contents are expressed in molar percentage: SiO2 20-30%, B2O3 10-20%, Li2CO3 10-20%, K2CO3 1-5%, Al2O3 1-5%, Cs2CO3 5-15%, PbBr2+PbI2 10-20%, and NaBr+NaI 5-15%.

9. The method according to any one of claims 1 to 3, characterized in that: In step (1), the high-temperature melting conditions in the melt water quenching method or melt casting are: heating to 1000-1700°C and keeping warm for 5-20 minutes; the heat treatment crystallization conditions are: heating to 450-600°C and keeping warm for 4-12 hours.

10. The method according to any one of claims 1 to 3, characterized in that: In step (3), the magnetic stirring speed is 500-3000 r / min, the stirring time is 10-50 min, and the ultrasonic cleaning time is 10-50 min.

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