CsPbBr3 perovskite quantum dot germanoborate glass material, preparation method and application thereof

Abstract

The application relates to the technical field of solid light-emitting materials, in particular to a CsPbBr3 perovskite quantum dot germanoborate glass material and a preparation method and application thereof. The CsPbBr3 perovskite quantum dot germanoborate glass material provided by the application comprises, in terms of the mass fraction, GeO2 25-29 parts, H3BO3 100-108 parts, ZnO 2-6 parts, SrCO3 1-4 parts, Cs2CO3 3-8 parts, PbO 2-7 parts and NaBr 1-8 parts. The perovskite quantum dots are embedded in the germanoborate glass, the environmental stability of the perovskite quantum dots is improved, and the application prospect of the perovskite quantum dots in photoelectric devices is expanded. Further, by introducing LiF into the perovskite quantum dot germanoborate glass material, the fluorescence quantum yield of the perovskite quantum dot glass is improved, and the environmental stability of the perovskite quantum dots is further improved.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of solid light-emitting materials, in particular to a CsPbBr3 perovskite quantum dot germanate glass material and a preparation method and application thereof. BACKGROUND

[0002] Perovskite quantum dots refer to semiconductor nanoparticles with a perovskite crystal structure (cubic crystal structure with a structural formula of ABX3), and the nanoparticles exhibit quantum confinement effect, that is, the optical and electrical properties thereof are affected by the size and shape thereof. Perovskite quantum dot materials have been widely concerned in the fields of optoelectronic devices, light-emitting diodes (LEDs), photovoltaic cells and optical sensing due to their excellent photoelectric properties (such as high optical absorption coefficient, narrow emission spectral line width, high fluorescence quantum yield and adjustable spectral range). However, the existing perovskite quantum dot materials are susceptible to environmental factors such as humidity, heat and oxygen, and have poor environmental stability, which seriously limits their application in practice. SUMMARY

[0003] Therefore, the purpose of the application is to provide a CsPbBr3 perovskite quantum dot germanate glass material and a preparation method and application thereof. The CsPbBr3 perovskite quantum dot germanate glass material provided by the application has good environmental stability of perovskite quantum dots.

[0004] In order to achieve the above-mentioned purpose of the application, the application provides the following technical solutions.

[0005] The application provides a CsPbBr3 perovskite quantum dot germanate glass material, and the chemical composition of the CsPbBr3 perovskite quantum dot germanate glass material includes, in terms of the amount of substance, 25-29 parts of GeO2, 100-108 parts of H3BO3, 2-6 parts of ZnO, 1-4 parts of SrCO3, 3-8 parts of Cs2CO3, 2-7 parts of PbO and 1-8 parts of NaBr.

[0006] Preferably, the chemical composition of the CsPbBr3 perovskite quantum dot germanate glass material further includes 0-4 parts of LiF in terms of the amount of substance, and the amount of LiF is not 0.

[0007] Preferably, the chemical composition of the CsPbBr3 perovskite quantum dot germanate glass material includes, in terms of the amount of substance, 25-29 parts of GeO2, 100-108 parts of H3BO3, 4 parts of ZnO, 2 parts of SrCO3, 6 parts of Cs2CO3, 4 parts of PbO, 5 parts of NaBr and 0-4 parts of LiF.

[0008] The application provides a preparation method of the CsPbBr3 perovskite quantum dot germanate glass material.

[0009] According to the chemical composition of the CsPbBr3 perovskite quantum dot germanate glass material, the raw materials are mixed and melted to obtain a glass melt;

[0010] The glass melt is subjected to casting forming and annealing to obtain the CsPbBr3 perovskite quantum dot germanate glass material.

[0011] Preferably, the melting temperature is 950-1050℃, and the time is 10-30min.

[0012] Preferably, the annealing temperature is 300-400℃, and the time is 2-4h.

[0013] Preferably, the casting forming time is <6min.

[0014] Preferably, the casting forming comprises: pouring the glass melt onto a preheated preheating plate and standing.

[0015] Preferably, the temperature of the preheated preheating plate is 300-450℃; and the pouring time is <1min.

[0016] The application provides application of the CsPbBr3 perovskite quantum dot germanate glass material in photoelectric devices or photovoltaic cells.

[0017] The application provides a CsPbBr3 perovskite quantum dot germanate glass material, which has a chemical composition comprising, in terms of mole fraction, 25-29 parts of GeO2, 100-108 parts of H3BO3, 2-6 parts of ZnO, 1-4 parts of SrCO3, 3-8 parts of Cs2CO3, 2-7 parts of PbO and 1-8 parts of NaBr.

[0018] Further, by introducing LiF (lithium fluoride) into the CsPbBr3 perovskite quantum dot germanate glass material, the application not only improves the luminescence performance of the perovskite quantum dot and the fluorescence quantum yield of the perovskite quantum dot glass, but also further improves the environmental stability of the perovskite quantum dot.

[0019] The preparation method of the CsPbBr3 perovskite quantum dot germanate glass material provided in the technical scheme has the advantages that the germanate glass is prepared by using a traditional melt quenching method, the CsPbBr3 perovskite quantum dot is successfully prepared in the germanate glass by using a self-crystallization method, and the CsPbBr3 perovskite quantum dot has excellent environmental stability; in addition, the preparation method is simple in operation, low in cost, small in environmental pollution, and suitable for industrialized production. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 The (a) emission spectrum and (b) fluorescence quantum dot yield spectrum of the CsPbBr3 perovskite quantum dot germanate glass material prepared for Examples 1-5 are shown in the figure;

[0021] Figure 2 The (a) XRD diffraction pattern and (b) high-resolution transmission electron microscopy pattern of the CsPbBr3 perovskite quantum dot germanate glass material prepared for Examples 1-5 are shown in the figure;

[0022] Figure 3 The (a) Raman spectrum and (b) Fourier infrared spectrum of the CsPbBr3 perovskite quantum dot germanate glass material prepared for Examples 1-5 are shown in the figure;

[0023] Figure 4 The luminescence results of the CsPbBr3 perovskite quantum dot germanate glass material prepared for Examples 1-5 soaked in water for 1-30 days are shown in the figure;

[0024] Figure 5 The photoluminescence intensity of PG2 prepared for Example 3 soaked in water for 1-30 days is shown in the figure;

[0025] Figure 6 The stability test results of the traditional colloidal perovskite quantum dots prepared for Comparative Example 1 soaked in water for 30 days are shown in the figure;

[0026] Figure 7 The photoluminescence intensity of PG2 prepared for Example 3 in the temperature range of 300 to 420K is shown in the figure;

[0027] Figure 8 The photoluminescence intensity of the PG2 sample prepared for Example 3 continuously irradiated under a 365nm ultraviolet lamp for 30 days is shown in the figure. DETAILED DESCRIPTION

[0028] The application provides a CsPbBr3 perovskite quantum dot germanate glass material, and the chemical composition comprises, in terms of the number of substance parts, GeO2 25-29 parts, H3BO3 100-108 parts, ZnO 2-6 parts, SrCO3 1-4 parts, Cs2CO3 3-8 parts, PbO 2-7 parts and NaBr 1-8 parts.

[0029] The CsPbBr3 perovskite quantum dot germanate glass material provided by the application has a chemical composition including GeO2 25-29 parts by mass, and in specific embodiments, the amount of GeO2 can be 25 parts by mass, 26 parts by mass, 27 parts by mass, 28 parts by mass or 29 parts by mass.

[0030] The CsPbBr3 perovskite quantum dot germanate glass material provided by the application has a chemical composition including H3BO3 100-108 parts by mass, and in specific embodiments, the amount of H3BO3 can be 100 parts by mass, 101 parts by mass, 102 parts by mass, 103 parts by mass, 104 parts by mass, 105 parts by mass, 106 parts by mass, 107 parts by mass or 108 parts by mass, based on the amount of GeO2.

[0031] The CsPbBr3 perovskite quantum dot germanate glass material provided by the application has a chemical composition including ZnO 2-6 parts by mass, and in specific embodiments, the amount of ZnO can be 2 parts by mass, 3 parts by mass, 4 parts by mass, 5 parts by mass or 6 parts by mass, based on the amount of GeO2.

[0032] The CsPbBr3 perovskite quantum dot germanate glass material provided by the application has a chemical composition including SrCO3 1-4 parts by mass, and in specific embodiments, the amount of SrCO3 can be 1 part by mass, 2 parts by mass, 3 parts by mass or 4 parts by mass, based on the amount of GeO2.

[0033] The CsPbBr3 perovskite quantum dot germanate glass material provided by the application has a chemical composition including Cs2CO3 3-8 parts by mass, and in specific embodiments, the amount of Cs2CO3 can be 3 parts by mass, 4 parts by mass, 5 parts by mass, 6 parts by mass, 7 parts by mass or 8 parts by mass, based on the amount of GeO2.

[0034] The CsPbBr3 perovskite quantum dot germanate glass material provided by the application has a chemical composition including PbO 2-7 parts by mass, and in specific embodiments, the amount of PbO can be 2 parts by mass, 3 parts by mass, 4 parts by mass, 5 parts by mass, 6 parts by mass or 7 parts by mass, based on the amount of GeO2.

[0035] The CsPbBr3 perovskite quantum dot germanate glass material provided by the application has a chemical composition including NaBr 1-8 parts by mass, and in specific embodiments, the amount of NaBr can be 1 part by mass, 2 parts by mass, 3 parts by mass, 4 parts by mass, 5 parts by mass, 6 parts by mass, 7 parts by mass or 8 parts by mass, based on the amount of GeO2.

[0036] The CsPbBr3 perovskite quantum dot germanate glass material provided by the application can further comprise 0-4 parts of LiF based on the parts by mass of GeO2, and the amount of LiF is not 0, and in specific embodiments, the parts by mass of LiF can be 1 part, 2 parts, 3 parts or 4 parts.

[0037] In the application, the chemical composition of the CsPbBr3 perovskite quantum dot germanate glass material can comprise 25-29 parts by mass of GeO2, 100-108 parts by mass of H3BO3, 4 parts of ZnO, 2 parts of SrCO3, 6 parts of Cs2CO3, 4 parts of PbO, 5 parts of NaBr and 0-4 parts of LiF.

[0038] The application provides a preparation method of the CsPbBr3 perovskite quantum dot germanate glass material, comprising the following steps:

[0039] According to the chemical composition of the CsPbBr3 perovskite quantum dot germanate glass material, the preparation raw materials are mixed and melted to obtain a glass melt.

[0040] The glass melt is subjected to casting forming and annealing to obtain the CsPbBr3 perovskite quantum dot germanate glass material.

[0041] Unless otherwise specified, the materials and equipment used in the application are commercially available in the art.

[0042] According to the chemical composition of the CsPbBr3 perovskite quantum dot germanate glass material, the preparation raw materials are mixed and melted to obtain a glass melt. In the application, the parts by mass of the optional preparation raw materials can be the same as the parts by mass of the chemical composition of the prepared CsPbBr3 perovskite quantum dot germanate glass material, which will not be described here.

[0043] In the application, the melting temperature can be 950-1050℃, and in specific embodiments, the melting temperature can be 950℃, 980℃, 1000℃, 1020℃ or 1050℃; the melting time can be 10-30 min, and in specific embodiments, the melting time can be 10 min, 15 min, 20 min, 25 min or 30 min. In specific embodiments, the mixing can comprise grinding mixing; the application does not have special limitations on the time of grinding mixing and the particle size of the mixed material obtained by grinding mixing, and the preparation raw materials can be completely mixed. In the application, the particle size of the mixed material obtained by grinding mixing can be 1-5 μm, and in specific embodiments, it can be 1 μm, 2 μm, 3 μm, 4 μm or 5 μm.

[0044] The obtained mixture is placed in a crucible, and the crucible is placed in a muffle furnace for melting, wherein the crucible can be an alumina crucible, and the muffle furnace can be a silicon carbide muffle furnace.

[0045] After obtaining the glass melt, the glass melt is subjected to isothermal annealing to obtain the CsPbBr3 perovskite quantum dot germanoborate glass material.

[0046] In the present application, the time for isothermal annealing can be 2-4 h, and in specific embodiments, the time for isothermal annealing can be 2 h, 2.5 h, 3 h, 3.5 h or 4 h.

[0047] In specific embodiments, the isothermal annealing can be performed in an annealing furnace.

[0048] In specific embodiments, the temperature for isothermal annealing can be the same as that of the preheated preheating plate, which is not described herein again. The preheated preheating plate after pouring is subjected to isothermal annealing to prevent the glass block from being broken due to rapid temperature drop of the glass melt.

[0049] In the present application, the temperature for isothermal annealing can be 300-400℃, and in specific embodiments, the temperature for isothermal annealing can be 300℃, 320℃, 350℃, 370℃ or 400℃; the time for isothermal annealing can be 2-4 h, and in specific embodiments, the time for isothermal annealing can be 2 h, 2.5 h, 3 h, 3.5 h or 4 h. In specific embodiments, the isothermal annealing can be performed in an annealing furnace.

[0050] After the isothermal annealing is completed, the obtained annealed glass can be cooled to room temperature to obtain the CsPbBr3 perovskite quantum dot germanoborate glass material. In specific embodiments, the cooling can include cooling with the annealing furnace. The annealed glass obtained by annealing is cooled to room temperature with the furnace, which eliminates the internal stress of the glass and improves the environmental stability of the obtained CsPbBr3 perovskite quantum dot germanoborate glass material.

[0051] The application provides application of the CsPbBr3 perovskite quantum dot germanate glass material in a photoelectric device or a photovoltaic cell. In specific embodiments, the photoelectric device can be a light-emitting diode. The CsPbBr3 perovskite quantum dot germanate glass material provided by the application has good environmental stability, and can maintain strong light emission in different environments when applied in a photoelectric device or a photovoltaic cell.

[0052] In order to further illustrate the application, a CsPbBr3 perovskite quantum dot germanate glass material provided by the application, a preparation method and application thereof are described in detail below in combination with examples, but they should not be understood as limiting the protection scope of the application.

[0053] Example 1

[0054] The preparation raw materials of GeO2 27 parts, H3BO3 104 parts, ZnO 4 parts, SrCO3 2 parts, Cs2CO3 6 parts, PbO 4 parts and NaBr 5 parts are ground and mixed to a particle size of about 2 μm, loaded into an alumina crucible, placed in a muffle furnace, and melted at 1000℃ for 20 min to obtain a glass melt.

[0055] The obtained glass melt is poured onto a preheated plate preheated to 400℃ within 1 min, placed for 5 min, then transferred to an annealing furnace, annealed at 350℃ for 3 h, and cooled to room temperature with the annealing furnace to obtain a CsPbBr3 perovskite quantum dot germanate glass material (denoted as PG0).

[0056] Example 2

[0057] The CsPbBr3 perovskite quantum dot germanate glass material (denoted as PG1) is prepared according to the preparation method in Example 1, and the only difference from Example 1 is that the preparation raw materials are GeO2 27 parts, H3BO3 104 parts, ZnO 4 parts, SrCO3 2 parts, Cs2CO3 6 parts, PbO 4 parts, NaBr 5 parts and LiF 1 part in terms of substance amount.

[0058] Example 3

[0059] The CsPbBr3 perovskite quantum dot germanate glass material (denoted as PG2) is prepared according to the preparation method in Example 1, and the only difference from Example 1 is that the preparation raw materials are GeO2 27 parts, H3BO3 104 parts, ZnO 4 parts, SrCO3 2 parts, Cs2CO3 6 parts, PbO 4 parts, NaBr 5 parts and LiF 2 parts in terms of substance amount.

[0060] Example 4

[0061] CsPbBr3perovskite quantum dot germanoborosilicate glass material (denoted as PG3) was prepared according to the preparation method in Example 1, the only difference from Example 1 is that the preparation raw materials are: GeO227 parts, H3BO3104 parts, ZnO 4 parts, SrCO32 parts, Cs2CO36 parts, PbO 4 parts, NaBr 5 parts and LiF 3 parts in terms of the amount of substance.

[0062] Example 5

[0063] CsPbBr3perovskite quantum dot germanoborosilicate glass material (denoted as PG4) was prepared according to the preparation method in Example 1, the only difference from Example 1 is that the preparation raw materials are: GeO227 parts, H3BO3104 parts, ZnO 4 parts, SrCO32 parts, Cs2CO36 parts, PbO 4 parts, NaBr 5 parts and LiF 4 parts in terms of the amount of substance.

[0064] Comparative Example 1

[0065] The traditional colloidal perovskite quantum dots were prepared according to the literature (Daqin Chen, Shuo Yuan, Jiangkun Chen, et al. Robust CsPbX3(X = Cl, Br, and I) perovskite quantum dot embedded glasses: nanocrystallization, improved stability and visible full-spectral tunable. [J] Journal of Materials Chemistry C, 2018, 6, 12864).

[0066] Figure 1 The (a) emission spectrum and (b) fluorescence quantum dot yield spectrum of the CsPbBr3perovskite quantum dot germanoborosilicate glass material (a) prepared in Examples 1-5. It can be seen from Figure 1 (a) that LiF doping can improve the photoluminescence intensity of the CsPbBr3perovskite quantum dot germanoborosilicate glass material, when the doping concentration of LiF is 2 mol%, the photoluminescence intensity of the CsPbBr3perovskite quantum dot reaches the strongest, further increasing the doping concentration of LiF will reduce the photoluminescence intensity of the CsPbBr3perovskite quantum dot (may be caused by concentration quenching phenomenon). From Figure 1 (b), it can be seen that LiF doping can improve the photoluminescence intensity of the CsPbBr3perovskite quantum dot germanoborosilicate glass material from 10.5% to 49.3%.

[0067] Figure 2 The images show (a) XRD diffraction patterns and (b) high-resolution transmission electron microscopy (TEM) images of the CsPbBr3 perovskite quantum dot germanium borate glass materials prepared in Examples 1-5. Figure 2 As shown in (a), because the self-crystallized glass cannot provide high-energy thermal energy, and the size of the CsPbBr3 perovskite quantum dots is small, no XRD diffraction peaks corresponding to the CsPbBr3 perovskite quantum dots can be detected. Figure 2 The black spheres can be observed using a high-resolution transmission electron microscope in (b), and the interplanar spacing can be calculated to be... The (223) crystal plane of the CsPbBr3 perovskite quantum dots indicates that CsPbBr3 perovskite quantum dots were precipitated in the prepared CsPbBr3 perovskite quantum dot germanoborate glass material.

[0068] Figure 3 The images show (a) Raman and (b) Fourier transform infrared spectra of the CsPbBr3 perovskite quantum dot germanium borate glass materials prepared in Examples 1-5. Figure 3 It can be seen that with the increase of LiF doping concentration, the intensity of the symmetric stretching vibration band corresponding to the BOB bond and the bending vibration of the boron-oxygen ring increases. This is because some [BO] 4] The transformation from tetrahedrons to [BO3]trigonal structures causes the network structure of glass materials to change from a three-dimensional framework structure to a two-dimensional layered structure. This also makes the glass materials more loose, promoting the migration of cesium ions, lead ions and bromide ions, and thus promoting the generation of CsPbBr3 perovskite quantum dots.

[0069] Figure 4 The images show the luminescence results of the CsPbBr3 perovskite quantum dot germanium borate glass materials prepared in Examples 1-5 after immersion in water for 1-30 days. Figure 4 It can be seen that after being soaked in water for 30 days, the CsPbBr3 perovskite quantum dot germanium borate glass material still exhibits strong luminescence, indicating that the prepared CsPbBr3 perovskite quantum dot germanium borate glass material has excellent water stability.

[0070] Taking PG2 as an example, Figure 5 The image shows the photoluminescence intensity of PG2 obtained in Example 3 after immersion in water for 1–30 days. Figure 5 It can be seen that after soaking in water for 30 days, the photoluminescence intensity of the PG2 sample remained at 79.7% of the initial value, indicating that the CsPbBr3 perovskite quantum dot glass material prepared in this invention has good water stability.

[0071] Figure 6 The results of the stability test of the traditional colloidal perovskite quantum dots prepared in Comparative Example 1 after immersion in water for 30 days are provided by [the relevant authority / organization].Figure 6 It can be seen that the CsPbBr3 perovskite quantum dot glass material prepared in the application still has strong luminescence after being soaked in water for 30 days, while the traditional colloidal perovskite quantum dots prepared in Comparative Example 1 lose luminescence after being soaked in water for several hours.

[0072] Figure 7 The photoluminescence intensity of PG2 prepared in Example 3 in the temperature range of 300 to 420 K is shown in the figure. Figure 7 It can be seen that the luminescence intensity of PG2 decreases during the temperature rise, which is due to the increase of non-radiative transition probability caused by temperature rise. When the temperature gradually decreases to 300 K, the luminescence intensity of PG2 remains above 80% of the luminescence intensity before temperature rise, which indicates that the CsPbBr3 perovskite quantum dot glass material prepared in the application has good temperature resilience (thermal stability).

[0073] Figure 8 The photoluminescence intensity of the PG2 sample prepared in Example 3 under continuous irradiation of 365 nm ultraviolet light for 30 days is shown in the figure. Figure 8 It can be seen that the photoluminescence intensity of PG2 is 85.9% of the original value after continuous irradiation under ultraviolet light for 30 days, which indicates that the CsPbBr3 perovskite quantum dot glass material prepared in the application has good light stability.

[0074] In summary, the CsPbBr3 perovskite quantum dot germanate glass material provided in the application has excellent water stability, light stability and thermal stability, and excellent environmental stability. Moreover, through LiF doping and self-crystallization, the CsPbBr3 perovskite quantum dot glass material with high luminescence intensity and high water stability can be prepared in the germanate glass.

[0075] The above only describes the preferred embodiments of the application, and it should be noted that those skilled in the art can make several improvements and refinements without departing from the principles of the application, and these improvements and refinements should also be considered as the protection scope of the application.

Claims

1. A CsPbBr3perovskite quantum dot germanoborate glass material, the chemical composition comprising, in terms of mole fraction: GeO2 25~29 parts, H3BO3 100~108 parts, ZnO 2~6 parts, SrCO3 1~4 parts, Cs2CO3 3~8 parts, PbO 2~7 parts and NaBr 1~8 parts; The CsPbBr3 perovskite quantum dot germanate glass material has a chemical composition including, in terms of the amount of substance, GeO2 25~29 parts, H3BO3 100~108 parts, ZnO 4 parts, SrCO3 2 parts, Cs2CO3 6 parts, PbO 4 parts, NaBr 5 parts and LiF 0~4 parts.

2. The CsPbBr3perovskite quantum dot germanoborosilicate glass material of claim 1, wherein, The CsPbBr3 perovskite quantum dot germanate glass material has a chemical composition including, in terms of the amount of substance, GeO2 25~29 parts, H3BO3 100~108 parts, ZnO 4 parts, SrCO3 2 parts, Cs2CO3 6 parts, PbO 4 parts, NaBr 5 parts and LiF 0~4 parts.

3. The method for preparing CsPbBr3 perovskite quantum dot germanoborate glass material according to any one of claims 1-2, characterized in that, The method comprises the following steps: According to the chemical composition of the CsPbBr3 perovskite quantum dot germanate glass material, the raw materials are mixed and melted to obtain a glass melt. The glass melt is subjected to annealing after casting forming to obtain the CsPbBr3 perovskite quantum dot germanate glass material.

4. The production method according to claim 3, characterized by, The melting temperature is 950~1050℃, and the time is 10~30 min.

5. The preparation method according to claim 3, characterized in that, The annealing temperature is 300~400℃, and the time is 2~4 h.

6. The preparation method according to claim 3, characterized in that, The casting forming time is <6 min.

7. The production method according to claim 3 or 6, characterized by, The casting forming comprises: pouring the glass melt onto a preheated preheating plate and standing.

8. The method of claim 7, wherein, The temperature of the preheated preheating plate is 300~450℃, and the pouring time is <1 min.

9. Use of the CsPbBr3 perovskite quantum dot germanate glass material of any one of claims 1~2 or the CsPbBr3 perovskite quantum dot germanate glass material prepared by the method of any one of claims 3~8 in an optoelectronic device or a photovoltaic cell.

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