A method for growing CsPbBr3 single crystals in a simple solvent system
By adding n-butanol to dimethyl sulfoxide solvent in a simple solvent system and combining it with reverse temperature crystallization, the nucleation and growth of CsPbBr3 single crystals were controlled, solving the problems of uncontrollable nucleation and defects, and obtaining high-quality CsPbBr3 single crystals suitable for optoelectronic devices such as radiation detectors.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SHANGHAI TECHN INST OF ELECTRONICS & INFORMATION
- Filing Date
- 2026-03-27
- Publication Date
- 2026-06-30
AI Technical Summary
The uncontrollable nucleation, excessively rapid local growth leading to encapsulation defects, and temperature-induced internal stress cracks during the preparation of existing CsPbBr3 single crystals affect crystal transparency and device performance consistency.
A method for growing CsPbBr3 single crystals using a simple solvent system was employed. By adding n-butanol as an additive to dimethyl sulfoxide, nucleation was controlled and stable growth was achieved at a lower temperature. Crystal growth was carried out using a reverse-temperature crystallization method, with control over the temperature rise rate and holding time.
It achieves low defect density, high transparency and structural integrity of CsPbBr3 single crystals, making them suitable for optoelectronic devices such as radiation detectors.
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Figure CN122304028A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of room temperature semiconductor radiation detector materials and device fabrication technology, specifically a method for growing CsPbBr3 single crystals in a simple solvent system. Background Technology
[0002] Metal halide perovskite single crystals have great potential applications in photoelectric detection and radiation detection due to their excellent photoelectric properties and low defect density. Among them, all-inorganic CsPbBr3 single crystals have attracted widespread attention due to their good environmental stability and device compatibility.
[0003] Existing methods for preparing CsPbBr3 single crystals mainly employ solutions-based inverted temperature crystallization, but problems such as uncontrollable nucleation, encapsulation defects caused by excessively rapid local growth, and internal stress cracks caused by temperature processes can still easily occur during the growth process, thus affecting crystal transparency, structural integrity, and device performance consistency.
[0004] Therefore, it is necessary to provide a method for preparing CsPbBr3 single crystals that can achieve controllable nucleation and stable growth under milder conditions and reduce defect generation. Summary of the Invention
[0005] To address the problems existing in the prior art, this invention provides a method for growing CsPbBr3 single crystals in a simple solvent system, specifically including the following steps: (1) Cesium bromide (CsBr) and lead bromide (PbBr2) were dissolved in dimethyl sulfoxide. After the cesium bromide (CsBr) and lead bromide (PbBr2) were completely dissolved, n-butanol was added and stirred evenly under heating. The resulting solution was filtered to obtain a transparent and homogeneous CsPbBr3 precursor solution.
[0006] (2) Place the seed crystal in a CsPbBr3 precursor solution at a temperature of 49-51℃ and keep it warm. After the seed crystal dissolves and enters a stable growth state, raise the temperature to 52-75℃ at a rate of 1℃ / day for reverse temperature crystallization growth. When the temperature reaches 52-75℃, keep it warm until the target size of CsPbBr3 single crystal is obtained. Take it out and clean it to remove the residual precursor solution on the crystal surface. The CsPbBr3 single crystal is obtained and sealed for storage.
[0007] Preferably, in step (1), the amount of dimethyl sulfoxide used is such that CsBr and PbBr2 are completely dissolved, and the volume ratio of dimethyl sulfoxide (DMSO) to n-butanol (NBA) is 3:1.
[0008] Preferably, in step (1), a polytetrafluoroethylene (PTFE) filter with a pore size of 0.22 μm is used for filtration.
[0009] Preferably, the heating temperature in step (1) is 40-50℃.
[0010] Preferably, in step (2), the crystal cleaning is performed using N,N-dimethylformamide solvent for rapid cleaning.
[0011] Compared with the prior art, the present invention has the following beneficial effects: (1) The present invention uses n-butanol additive to regulate the dimethyl sulfoxide solvent system, so that CsPbBr3 can achieve stable growth in a lower temperature range of 52-75℃, effectively reducing the growth temperature and widening the controllable growth window.
[0012] (2) n-Butanol additives can regulate the dissolution-coordination balance in the precursor solution, making the crystal growth process smoother, thereby inhibiting instantaneous nucleation and the formation of defects.
[0013] (3) The CsPbBr3 single crystal prepared by the method of the present invention has lower defect density, higher transparency and better structural integrity, which is beneficial to its application in the field of optoelectronic devices such as radiation detectors. Attached Figure Description
[0014] Figure 1 Physical image of CsPbBr3 crystals obtained from Example 1.
[0015] Figure 2 X-ray diffraction pattern of CsPbBr3 crystals grown in Example 1.
[0016] Figure 3 High-resolution X-ray rocking (XRC) of CsPbBr3 crystals grown in Example 1.
[0017] Figure 4 A photograph of the CsPbBr3 crystal obtained from Comparative Example 1.
[0018] Figure 5 High-resolution X-ray rocking (XRC) of CsPbBr3 crystals grown in Comparative Example 1.
[0019] Figure 6 Dissolution-crystallization boundary curve of CsPbBr3 in DMSO / n-butanol system in Example 1. Detailed Implementation
[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0021] Example 1 A method for preparing CsPbBr3 single crystals by growing them in a simple solvent system, specifically including the following steps: (1) Preparation: First, the 20mL growth flask for crystal growth is prepared by rinsing the inner wall of the growth flask with deionized water, then sonicating it with anhydrous ethanol for 25 minutes, washing it three times with anhydrous ethanol, and then drying it in an oven for later use. Next, the crystal growth equipment is pretreated by turning on the temperature-controlled constant temperature drying oven, starting the temperature control program, raising the temperature to 50℃, adding silicone oil to a large beaker and placing it in the drying oven to heat the silicone oil in the beaker to 50℃ and stabilize it for later use.
[0022] (2) Preparation of CsPbBr3 precursor solution: Dimethyl sulfoxide (DMSO) was added to a mixture of cesium bromide (CsBr) and lead bromide (PbBr2) in a molar ratio of 1:2 (where CsBr was 3 mmol). The addition of DMSO was stopped after the cesium bromide and lead bromide were completely dissolved. Then n-butanol (NBA) (DMS to NBA volume ratio of 3:1) was added, and the mixture was stirred in a water bath at 40 °C to obtain a mixed solution. The mixed solution was filtered through a polytetrafluoroethylene (PTFE) filter with a pore size of 0.22 μm to obtain a CsPbBr3 precursor solution.
[0023] (3) Place the seed crystal in the oil bath: Transfer the CsPbBr3 precursor solution obtained in step (3) to a pre-dried growth flask and place a seed crystal at the center of the bottom of the growth flask. Place the growth flask containing the precursor solution into the silicone oil bath prepared in step (1) so that the silicone oil in the beaker completely submerges the precursor solution in the growth flask to ensure a stable temperature field.
[0024] (4) Inverted temperature crystallization (ITC) growth: The reverse temperature crystallization method was adopted. The growth bottle containing the seed crystal was placed in a 50℃ silicone oil bath and kept at that temperature for 24 hours. After the seed crystal underwent partial dissolution and entered a stable growth state, the temperature was increased to 70℃ at a rate of 1℃ / day for growth. When the seed crystal grew to the target size (4mm×5mm×2mm), the crystal was removed and quickly cleaned with N,N-dimethylformamide (DMF) solvent. Then, the residual precursor solution on the crystal surface was removed with a lint-free cloth to obtain CsPbBr3 crystals. The sample bottle containing the CsPbBr3 single crystal was vacuum sealed using a sealing machine and stored in a dry area.
[0025] Example 2 A method for preparing CsPbBr3 single crystals by growing them in a simple solvent system, specifically including the following steps: (1) Preparation: First, the 20mL growth flask for crystal growth is prepared by rinsing the inner wall of the growth flask with deionized water, then sonicating it with anhydrous ethanol for 25 minutes, washing it three times with anhydrous ethanol, and then drying it in an oven for later use. Next, the crystal growth equipment is pretreated by turning on the temperature-controlled constant temperature drying oven, starting the temperature control program, raising the temperature to 49°C, adding silicone oil to a large beaker and placing it in the drying oven to heat the silicone oil in the beaker to 49°C and stabilize it for later use.
[0026] (2) Preparation of CsPbBr3 precursor solution: Dimethyl sulfoxide (DMSO) was added to a mixture of cesium bromide (CsBr) and lead bromide (PbBr2) in a molar ratio of 1:2 (where CsBr was 3 mmol). The addition of DMSO was stopped after the cesium bromide and lead bromide were completely dissolved. Then n-butanol (NBA) (DMS to NBA volume ratio of 3:1) was added, and the mixture was stirred evenly in a water bath at 45°C to obtain a mixed solution. The mixed solution was filtered through a polytetrafluoroethylene (PTFE) filter with a pore size of 0.22 μm to obtain a CsPbBr3 precursor solution.
[0027] (3) Place the seed crystal in the oil bath: Transfer the CsPbBr3 precursor solution obtained in step (3) to a pre-dried growth flask and place a seed crystal at the center of the bottom of the growth flask. Place the growth flask containing the precursor solution into the silicone oil bath prepared in step (1) so that the silicone oil in the beaker completely submerges the precursor solution in the growth flask to ensure a stable temperature field.
[0028] (4) Inverted temperature crystallization (ITC) growth: The reverse temperature crystallization method was adopted. The growth bottle containing the seed crystal was placed in a silicone oil bath at 49℃ and kept at that temperature for 24 hours. After the seed crystal underwent partial dissolution and entered a stable growth state, the temperature was increased to 75℃ at a rate of 1℃ / day for growth. When the seed crystal grew to the target size (4mm×5mm×2mm), the crystal was removed and quickly cleaned with N,N-dimethylformamide (DMF) solvent. Then, the residual precursor solution on the crystal surface was removed with a lint-free cloth to obtain CsPbBr3 crystals. The sample bottle containing the CsPbBr3 single crystal was vacuum sealed using a sealing machine and stored in a dry area.
[0029] Example 3 A method for preparing CsPbBr3 single crystals by growing them in a simple solvent system, specifically including the following steps: (1) Preparation: First, the 20mL growth flask for crystal growth is prepared by rinsing the inner wall of the growth flask with deionized water, then sonicating it with anhydrous ethanol for 25 minutes, washing it three times with anhydrous ethanol, and then drying it in an oven for later use. Next, the crystal growth equipment is pretreated by turning on the temperature-controlled constant temperature drying oven, starting the temperature control program, raising the temperature to 51℃, adding silicone oil to a large beaker and placing it in the drying oven to heat the silicone oil in the beaker to 51℃ and stabilize it for later use.
[0030] (2) Preparation of CsPbBr3 precursor solution: Dimethyl sulfoxide (DMSO) was added to a mixture of cesium bromide (CsBr) and lead bromide (PbBr2) in a molar ratio of 1:2 (where CsBr was 3 mmol). The addition of DMSO was stopped after the cesium bromide and lead bromide were completely dissolved. Then n-butanol (NBA) (DMS to NBA volume ratio of 3:1) was added, and the mixture was stirred evenly in a water bath at 50 °C to obtain a mixed solution. The mixed solution was filtered through a polytetrafluoroethylene (PTFE) filter with a pore size of 0.22 μm to obtain a CsPbBr3 precursor solution.
[0031] (3) Place the seed crystal in the oil bath: Transfer the CsPbBr3 precursor solution obtained in step (3) to a pre-dried growth flask and place a seed crystal at the center of the bottom of the growth flask. Place the growth flask containing the precursor solution into the silicone oil bath prepared in step (1) so that the silicone oil in the beaker completely submerges the precursor solution in the growth flask to ensure a stable temperature field.
[0032] (4) Inverted temperature crystallization (ITC) growth: The reverse temperature crystallization method was adopted. The growth bottle containing the seed crystal was placed in a silicone oil bath at 51℃ for 24 hours to allow the seed crystal to partially dissolve and enter a stable growth state. Then, the temperature was increased to 52℃ at a rate of 1℃ / day for growth. When the seed crystal grew to the target size (4mm×5mm×2mm), the crystal was removed and quickly cleaned with N,N-dimethylformamide (DMF) solvent. Then, the residual precursor solution on the crystal surface was removed with a lint-free cloth to obtain CsPbBr3 crystals. The sample bottle containing the CsPbBr3 single crystal was vacuum sealed using a sealing machine and stored in a dry area.
[0033] Comparative Example 1 CsPbBr3 single crystals were grown using a dimethyl sulfoxide / N,N-dimethylformamide / cyclohexanol mixed solvent system, specifically including the following steps: (1) Preparation: Same as Example 1.
[0034] (2) Preparation of CsPbBr3 precursor solution: A mixture of cesium bromide (CsBr) and lead bromide (PbBr2) in a molar ratio of 1:2 (where CsBr is 3 mmol) was added to a mixed solution of dimethyl sulfoxide (DMSO) and N,N-dimethylformamide (DMF) (the volume ratio of DMSO to N,N-dimethylformamide is 3:1). The addition of the mixed solution was stopped after the cesium bromide and lead bromide were completely dissolved. Cyclohexanol (the volume ratio of the mixed solution to cyclohexanol is 3:1) was then added, and the mixture was stirred continuously in a water bath at 40°C to obtain a mixed solution. The mixed solution was filtered through a polytetrafluoroethylene (PTFE) filter with a pore size of 0.22 μm to obtain a CsPbBr3 precursor solution.
[0035] (3) Place the seed crystal in the oil bath: Transfer the CsPbBr3 precursor solution obtained in step (3) to a pre-dried growth flask and place a seed crystal at the center of the bottom of the growth flask. Place the growth flask containing the precursor solution into the silicone oil bath prepared in step (1) so that the silicone oil in the beaker completely submerges the precursor solution in the growth flask to ensure a stable temperature field.
[0036] (4) Inverted temperature crystallization (ITC) growth: The reverse temperature crystallization method was adopted. The growth bottle containing the seed crystal was placed in a 50℃ silicone oil bath and kept at that temperature for 24 hours. After the seed crystal underwent partial dissolution and entered a stable growth state, the temperature was increased to 52℃ at a rate of 1℃ / day for growth. When the seed crystal grew to the target size (4mm×5mm×2mm), the crystal was removed and quickly cleaned with N,N-dimethylformamide (DMF) solvent. Then, the residual precursor solution on the crystal surface was removed with a lint-free cloth to obtain CsPbBr3 crystals. The sample bottle containing the CsPbBr3 single crystal was vacuum sealed using a sealing machine and stored in a dry area.
[0037] Performance comparison explanation: The crystal obtained in Comparative Example 1 was compared with the crystal obtained in Example 1 in terms of crystal transparency, surface integrity, XRD, XRC, and electrical properties. The physical image, X-ray diffraction (XRD) pattern, and high-resolution X-ray rocking (XRC) curve of the CsPbBr3 crystal obtained in Example 1 are shown below. Figure 1 , Figure 2 and Figure 3 As shown; the physical image of the CsPbBr3 crystal and the high-resolution X-ray rocking (XRC) curve obtained in Comparative Example 1 are shown below. Figure 4 , Figure 5 . Figure 1 The CsPbBr3 single crystals grown with the introduction of NBA additives shown have good transparency. Figure 2 The single-crystal X-ray diffraction (XRD) pattern shown indicates that the grown CsPbBr3 crystal is a phase-pure crystal; Figure 3The narrow high-resolution X-ray rocking curve (XRC) of the single crystal shown indicates that the crystal structure obtained after introducing NBA additives is more complete, has less lattice distortion, and has higher crystal quality. Figure 4 The CsPbBr3 single crystal grown in Comparative Example 1 has poor transparency. Figure 5 The broad high-resolution X-ray rocking curve (XRC) of the single crystal indicates that the crystal quality obtained by growing it in the traditional solvent system is poor. For example... Figure 6 As shown, after the introduction of NBA, CsPbBr3 exhibits a more favorable dissolution-crystallization boundary characteristic for inverted crystallization in the DMSO / n-butanol system. Therefore, the introduction of NBA broadens the temperature window for controllable growth, enabling stable crystal growth at lower temperatures. The n-butanol additive also regulates the dissolution-coordination balance in the precursor solution, making the crystal growth process smoother and reducing the probability of instantaneous nucleation and the risk of inclusion defects caused by excessively rapid local crystallization. This is beneficial for obtaining CsPbBr3 single crystals with higher transparency and more complete structure. The CsPbBr3 crystals prepared in Examples 2 and 3 have similar properties to those in Example 1.
[0038] The use of a simple solvent system of DMSO / n-butanol provides a clearer process composition and simpler operating steps, which is more conducive to demonstrating the advantages of this invention in obtaining high-quality CsPbBr3 single crystals under simple solvent system conditions.
[0039] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.
Claims
1. A method for growing CsPbBr3 single crystals in a simple solvent system, characterized in that: Specifically, the following steps are included: (1) Cesium bromide and lead bromide were dissolved in dimethyl sulfoxide. After the cesium bromide and lead bromide were completely dissolved, n-butanol was added and stirred evenly under heating. The resulting solution was filtered to obtain a transparent and homogeneous CsPbBr3 precursor solution. (2) Place the seed crystal in a CsPbBr3 precursor solution at a temperature of 49-51℃ and keep it warm so that the seed crystal can dissolve and enter a stable growth state. Then, raise the temperature to 52-75℃ at a heating rate of 1℃ / day for reverse temperature crystallization growth. When the temperature reaches 52-75℃, keep it warm until the target size of CsPbBr3 single crystal is obtained. Take it out and clean it to obtain CsPbBr3 single crystal and seal it for storage.
2. The method for growing CsPbBr3 single crystals in a simple solvent system according to claim 1, characterized in that: In step (1), the molar ratio of cesium bromide to lead bromide is 1:
2.
3. The method for growing CsPbBr3 single crystals in a simple solvent system according to claim 1, characterized in that: In step (1), the amount of dimethyl sulfoxide used should be such that CsBr and PbBr2 are completely dissolved, and the volume ratio of dimethyl sulfoxide to n-butanol is 3:
1.
4. The method for growing CsPbBr3 single crystals in a simple solvent system according to claim 1, characterized in that: In step (1), a polytetrafluoroethylene filter is used for filtration.
5. The method for growing CsPbBr3 single crystals in a simple solvent system according to claim 1, characterized in that: The heating temperature in step (1) is 40-50℃.
6. The method for growing CsPbBr3 single crystals in a simple solvent system according to claim 1, characterized in that: In step (2), the crystal is cleaned using N,N-dimethylformamide.