CN117684248A - Method for promoting perovskite monocrystal growth by breathable flexible container and X-ray detector - Google Patents

Abstract

The invention relates to the technical field of semiconductors, and discloses a method for promoting perovskite monocrystal growth by using a breathable flexible container and an X-ray detector, wherein the method comprises the following steps: transferring the perovskite precursor liquid to a flexible container, and sealing the outlet at the top of the flexible silica gel container with polydimethylsiloxane liquid; standing the flexible container, accelerating the airflow transmission speed at the bottom of the flexible silica gel container, and promoting the self-driven nucleation growth of perovskite single crystals in the container; the flexible container is made of flexible materials, and the side wall is sealed by using adhesive tape. According to the invention, the flexible container is utilized to selectively control the diffusion of the organic solvent, prevent the permeation of perovskite raw materials, promote the spontaneous increase of nucleation driving force in the flexible container, and realize the room-temperature self-driven growth of perovskite single crystals; the introduction of mechanical stress and thermal stress caused by a hard container and temperature rise and reduction is avoided, the growth rate and crystallization quality of single crystals are obviously improved, and the method can be used for preparing a detection device with more excellent on-off ratio.

Description

A method of promoting perovskite single crystal growth in a breathable flexible container, X-ray detector

Technical field

The invention relates to the field of semiconductor technology, and specifically relates to a method for promoting the growth of perovskite single crystals in a breathable flexible container and an X-ray detector.

Background technique

Perovskite is a semiconductor optoelectronic material with excellent performance. Its application fields include solar cells, light-emitting diodes (LEDs), lasers, photodetectors, and radiation detectors. Among them, organic-inorganic hybrid perovskite crystals have the advantages of traditional organic and inorganic semiconductors: diverse crystal growth methods, low preparation costs, strong photoelectric conversion capabilities, and great development potential. The classic organic-inorganic hybrid perovskite single crystal growth vessel uses glass material, which is stable and hard in texture. Mechanical stress exists at the interface between the single crystal and the glass, causing the single crystal to adhere to the container wall and introducing additional defect damage, which will reduce the quality of the grown single crystal and thus affect the performance of the optoelectronic device.

The inversion growth method is a common method for preparing organic-inorganic mixed perovskite single crystals, which utilizes the difference in solubility of perovskite solutes in organic solvents at different temperatures for crystallization. This method controls the nucleation and growth rate of crystals through temperature. Single crystals usually need to experience a temperature difference of 30 to 100°C when harvested. Thermal stress causes the quality of single crystals to decrease. The anti-solvent method can avoid the formation of temperature differences and induce rapid growth of single crystals by extracting organic solvents. Commonly used reagents are highly toxic substances such as dichloromethane (DCM), which is not conducive to environmental protection and health requirements. At the same time, this method is harmful to single crystal growth. The speed controllability is poor and the quality of the grown crystals is low.

Invention patent CN112071989A discloses an improved method for slowly raising the temperature to prepare perovskite single crystals. This method first prepares seed crystal grains, then screens and transfers the seed crystals, and continues to grow in a new solution. Based on the X-rays prepared by this single crystal The detector exhibits good sensitivity and stability. However, the steps of this method are relatively cumbersome, requiring manual screening of seed crystals and subsequent growth, and the labor cost is high.

Invention patent CN115787059A discloses a method of using dual flexible polymer film interfaces to limit the growth of perovskite single crystals. This method can achieve supersaturated nucleation of the perovskite precursor solution through organic matter diffusion and grow into a perovskite single crystal film. The photodetector prepared based on this method achieves excellent performance. However, this method is limited to the preparation of thin film single crystals and cannot grow millimeter-sized single crystals that meet the requirements of radiation detection devices. At the same time, the confinement method inevitably introduces mechanical stress on the surface of the single crystal, and the surface morphology of the single crystal is relatively rough.

Contents of the invention

In order to solve the problem of single crystal defects caused by mechanical stress and thermal stress in the preparation method of perovskite single crystal in the prior art, the present invention provides a method for promoting the growth of perovskite single crystal in a breathable flexible container, which can automatically grow at room temperature. Drive the growth of high-quality single crystals, effectively avoid defect damage caused by mechanical stress or thermal stress, and improve the growth rate and quality of single crystals.

In order to achieve the above objects, the technical solution adopted by the present invention is:

A method for promoting the growth of perovskite single crystals in a breathable flexible container, including the steps:

Step 1: Dissolve the perovskite raw materials in an organic solvent to form a perovskite precursor solution;

Step 2: Transfer the perovskite precursor liquid to a flexible container, and seal the top outlet of the flexible silica gel container with polydimethylsiloxane;

Step 3: Leave the flexible container to stand still, accelerate the air flow transmission speed at the bottom of the flexible silicone container, and promote the self-driven nucleation and growth of perovskite single crystals in the container;

The flexible container is made of flexible material, and the side walls are sealed with tape.

The present invention uses flexible containers to replace glass containers to grow perovskite single crystals. Compared with glass containers, flexible containers can not only promote the diffusion of organic solvent gases, block the penetration of perovskite raw materials, promote the stable increase of internal nucleation driving force, and achieve High-quality self-driven growth of perovskite single crystals at room temperature, and the flexible contact between the container and the single crystal interface can reduce defect damage during the growth process. The method of the present invention not only avoids the thermal stress introduced during the heating and cooling process, but also avoids the inevitable introduction of mechanical stress on the single crystal surface by the confinement method. At the same time, it simplifies the growth process, is easy to operate, and significantly improves the single crystal growth rate and crystallization quality. The prepared single crystal can be used to prepare better detection devices.

The material of the flexible container includes at least one of silicone, rubber, latex, polyethylene, polypropylene, polyvinyl chloride, polystyrene, polyethylene terephthalate, gelatin, starch, and cellulose. ; These material containers can realize the vaporization and diffusion of organic solvents from the bottom. At the same time, they are softer than glass containers and other materials, avoiding the introduction of mechanical stress during the growth of single crystals.

The organic solvent includes at least one of γ-butyrolactone (GBL), N,N-dimethylformamide (DMF), and dimethyl sulfoxide (DMSO).

The general chemical formula of the perovskite precursor liquid is _Am BX _n , where m is a natural number from 1 to 4, and n is a natural number from 3 to 6;

The method of the present invention can be used to prepare a variety of perovskite single crystals, including zero-dimensional perovskite, one-dimensional perovskite, two-dimensional perovskite, and three-dimensional perovskite single crystals.

When preparing zero-dimensional perovskite, the general chemical formula is A ₄ BX ₆ , the general chemical formula for one-dimensional perovskite is A ₃ BX ₅ , the general chemical formula for two-dimensional perovskite is A 2 BX 4 , and the general chemical formula for three-dimensional perovskite is A ₂ BX ₄ The general chemical formula of titanium ore is ABX ₃ .

A in the general chemical formula includes positive monovalent lithium ions (Li ⁺ ), positive monovalent sodium ions (Na ⁺ ), positive monovalent potassium ions (K + ), positive monovalent cesium ions (Cs + ), positive monovalent cesium ions (Cs + ), positive monovalent sodium ions (Na ⁺ ), positive monovalent potassium ions (K + ), positive monovalent cesium ions (Cs ⁺ ), Valent rubidium ion (Rb ⁺ ), positive monovalent silver ion (Ag ⁺ ), methylamine ion (CH ₃ NH ₃ ⁺ ), formamidine ion (CH(NH ₂ ) ₂ ⁺ ), phenylethylamine ion (C ₆ H ₅ CH ₂ NH ₃ ⁺ ), ethylamine ion (CH ₃ CH ₂ NH ₃ ⁺ ), propylamine ion (CH ₃ (CH ₂ ) ₂ NH ₃ ⁺ ), butylamine ion (CH ₃ (CH ₂ ) ₃ NH ₃ ⁺ ), one or more of hexamethylenediamine ion (NH ₃ (CH ₂ ) ₆ NH ₃ ²⁺ ), amantadine ion (C ₁₀ H ₁₈ N ⁺ );

B in the general formula includes positive divalent lead ions (Pb ²⁺ ), positive divalent germanium ions (Ge ²⁺ ), positive divalent tin ions (Sn ²⁺ ), positive trivalent aluminum ions (Al ³⁺ ), positive trivalent bismuth ions ( Bi ³⁺ ), one or more of positive trivalent antimony ions (Sb ³⁺ ), positive trivalent gallium ions (Ga ³⁺ ), and positive trivalent indium ions (In ³⁺ );

^{In the} general chemical ^{formula ,} Kind or variety.

In step 1, the perovskite raw material includes at least one of AX, BX, BX ₂ and BX ₃ , where A, B and X are as described above.

In step 1, the perovskite raw materials are dissolved at -30~20°C and stirred for 8-20 hours to fully dissolve. It has been studied that the perovskite raw materials dissolve faster at low temperatures and can be more fully and quickly dissolved in the solvent. Shorten the exposure time of the precursor in the air, avoid oxidation, and improve the nucleation quality of subsequent single crystals.

The method of cooling and dissolving may include using the following refrigerators for refrigeration, such as at least one of refrigeration and freezing, ice bath, dry ice cooling, liquid nitrogen cooling, and liquid helium cooling;

In step 1, the molar concentrations of the perovskite raw materials in the perovskite precursor solution are 0.8-2.6 mol/L respectively; concentration deviations from this range will weaken the crystal quality, and in severe cases, lead to segregation of impurities.

The methods of accelerating the air flow transmission speed include adding any one or more of fans, air conditioners, ovens, and air circulation machines; by changing the air circulation rate around the flexible container, controlling the organic solvent diffusion rate, and regulating the organic-inorganic perovskite Single crystal growth rate.

The tape includes at least one of copper tape, BOPP tape, cloth tape, kraft paper tape, masking tape, fiber tape, PVC tape, and PE foam tape. By wrapping the side wall of the flexible container with tape, the organic solvent diffusion channel on the side is closed, and the nucleation of the single crystal side wall is suppressed, thereby achieving high-quality nucleation and growth of organic-inorganic mixed perovskite single crystals.

Preferably, the flexible container is sequentially cleaned with isopropyl alcohol, acetone, and propanol before use and then dried.

Further preferably, the flexible container is ultrasonically cleaned with isopropyl alcohol, acetone and propanol for 10-30 minutes respectively before use to remove dust, oil and other impurities on the inner wall of the container;

Further preferably, the cleaned flexible container is dried at 20-40°C for more than 24 hours. Since solvents such as water, isopropyl alcohol, propanol, and acetone have an impact on single crystal growth, the container should be dried as much as possible before use. Clean and dry.

Preferably, the bottom wall thickness of the flexible container is 1-5 mm; the bottom wall thickness determines the diffusion speed of the solution in the container and should not be too thick or too thin.

Preferably, the inner bottom wall of the flexible container should be flat.

The height of the flexible container is not less than 10mm, and the diameter is not less than 10mm.

The growth time of the perovskite single crystal in step 3 is 1-9 days; the growth environment is at room temperature; such as 0-40°C. The method of the present invention has a fast single crystal growth rate, and the organic solvent selectively passes through the flexible container at room temperature. The concentration of the perovskite precursor liquid inside the container increases, and the crystal nucleation driving force exceeds the potential barrier and then self-drives nucleation and growth. The nucleation time of single crystal is 1-5 days, and the growth time is 1-4 days.

Further preferably, when the perovskite precursor liquid is transferred to the flexible container in step 2, an organic filter head is used for transfer. The pore size of the organic filter head is 0.2-0.5 mm, and the filter diameter is above 10 mm.

The thickness of the perovskite single crystal grown by the method of the present invention is 0.1-20mm. Compared with the existing technology, the contact angle between the flexible container and the perovskite precursor liquid of this method is larger, which is beneficial to the growth process of the solute in the perovskite single crystal. The single crystal has a high base area/thickness ratio and crystallizes uniformly along the thickness direction.

The preparation method of the present invention uses a flexible container to grow organic-inorganic mixed perovskite single crystals, and utilizes the selective permeability of the flexible container to organic solvents and perovskite precursor liquids to promote the vaporization and diffusion of organic solvents. The perovskite precursor liquid in the container The concentration exceeds the critical nucleation range, enabling automatic growth of millimeter-thick single crystals at room temperature. This preparation method is automatic, simple and efficient. The single crystal is in flexible contact with the substrate at room temperature, avoiding the introduction of thermal stress and mechanical stress inside the single crystal, and promoting the preparation of high-quality single crystals. By designing an air flow transmission system (including an air flow blocking device and an air flow guiding device) at the bottom of the flexible container, the nucleation position and growth rate of the single crystal can be controlled, further improving the quality of the organic-inorganic mixed perovskite single crystal. Based on this single crystal The constructed ray detector has excellent on-off ratio, carrier mobility-lifetime product and stability.

The invention also provides an X-ray detector, including a single crystal grown by the method of the invention. The process of using this single crystal to prepare X-ray detectors includes:

After the single crystal is grown in step 3, use disposable medical sterilized tweezers to take out the single crystal. Dust-free gauze quickly absorbs the residual perovskite precursor solution on the surface of the single crystal. Use a nitrogen gun to clean the surface of the single crystal and store it in a glove box. . Electrodes are processed on the surface of the perovskite single crystal to prepare detection devices. The thickness of the electrodes is more than 10 nm and the spacing is more than 1 nm.

The electrodes are conventional conductive materials in this field, such as carbon electrode (C), indium tin oxide (ITO), gold (Au), platinum (Pt), silver (Ag), copper (Cu), aluminum (Al), chromium (Cr) ), at least one of lead (Pb), tin (Sn), indium (In), gallium (Ga), titanium (Ti) or chromium (Cr).

The electrode processing method is a conventional manufacturing method in this field, such as at least one of evaporation, sputtering, spray coating, printing, spin coating, hot pressing or cold pressing.

Compared with the prior art, the present invention has the following beneficial effects:

The present invention uses a flexible container as an environment, and places the perovskite precursor solution therein to perform self-driven growth at room temperature. The flexible container can selectively control the diffusion of organic solvents, block the penetration of perovskite raw materials, promote the spontaneous increase of nucleation driving force inside the flexible container, and realize the self-driven growth of perovskite single crystal at room temperature; not only because of the flexibility of the interface between the container and the single crystal Contact can also reduce defect damage during the growth process, avoid the introduction of thermal stress caused by heating and cooling, significantly improve the single crystal growth rate and crystal quality, and obtain single crystal finished products with fewer defects and larger sizes. It can be used to prepare detection devices with better switching ratio.

Description of the drawings

Figure 1 is a scanning electron microscope photograph of the surface of a single crystal grown on a flexible container in Example 1.

Figure 2 is a scanning electron microscope photo of the surface of a single crystal grown in a glass container in Comparative Example 1.

Figure 3 shows the Vickers hardness distribution on the surface of a single crystal grown in a flexible container in Example 1.

Figure 4 shows the Vickers hardness distribution on the surface of a single crystal grown in a glass container in Comparative Example 1.

Figure 5 is a comparison chart of the transmission spectra of two single crystals grown in Example 1 and Comparative Example 1.

Figure 6 is the result of carrier mobility-lifetime product of single crystal grown in a flexible container in Example 1.

Figure 7 shows the carrier mobility-lifetime product results of single crystal grown in a glass container in Comparative Example 1.

Figure 8 is a comparison chart of the switching ratio of detection devices prepared from two types of single crystals grown in Example 1 and Comparative Example 1.

Figure 9 is a rocking curve of a single crystal grown in a flexible container in Example 1.

Figure 10 is the rocking curve of a single crystal grown in a glass container of Comparative Example 1.

Figure 11 is a comparison chart of the growth speed of single crystals in Example 1 and Comparative Example 1, where 1 refers to the flexible container, 2 refers to the glass container, 3 refers to the single crystal grown in the flexible container of Example 1, and 4 refers to the glass container of Comparative Example 1. grown single crystal.

Figure 12 is a morphological distribution diagram of the single crystal grown in Comparative Example 2.

Figure 13 is a morphological distribution diagram of the single crystal grown in Comparative Example 3.

Detailed ways

In order to make the purpose, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with examples. It should be understood that the specific embodiments described here are only used to explain the present invention and are not intended to limit the present invention. Modifications or equivalent substitutions made by those skilled in the art on the basis of understanding the technical solutions of the present invention, without departing from the spirit and scope of the technical solutions of the present invention, shall be covered by the protection scope of the present invention.

The raw materials used in the following specific embodiments were all purchased from the market.

Example 1

In this example, silica gel is used as a flexible container to grow MAPbBr ₃ perovskite single crystal. The diameter of the container is 40mm, the height is 25mm, and the thickness is 2mm (including the bottom). The side walls are wrapped and sealed with copper tape. The specific steps to promote the growth of perovskite single crystals are:

Step 1: According to the order of adding 800mL isopropyl alcohol, 8000mL acetone, and 800mL propanol, place the silica gel container in the above liquid for ultrasonic cleaning for 15 minutes, 20 minutes, and 15 minutes respectively. The three cleaning times total 50 minutes. Pour the cleaned liquid into the waste liquid bucket, and place the silica gel container in the oven to dry for 24 hours. Set the temperature to 25°C.

Step 2: In the organic solvent DMF, mix 1.57g of methylamine bromide (MABr) and 4.11g of lead bromide (PbBr ₂ ) into 10mL of MAPbBr ₃ perovskite precursor solution, and stir magnetically at 0°C for 12 hours. Mix and set speed to 900 rpm.

Step 3: Filter the MAPbBr ₃ perovskite precursor liquid through a polytetrafluoroethylene filter head and transfer it to a silica gel container. The pore size of the filter head is 0.2-0.5mm, and the filter diameter is not less than 10mm. Use polydimethylsiloxane liquid. Seal the top outlet of the flexible silicone container.

Step 4: Let the flexible container stand still and use a fan to guide the airflow at the bottom of the container. The organic solvent DMF selectively passes through the silica gel container at room temperature. The concentration of MAPbBr ₃ perovskite precursor liquid inside the container increases, and the driving force for MAPbBr ₃ crystal nucleation exceeds the potential. After the barrier, the nucleation and growth are self-driven. The nucleation time of MAPbBr ₃ single crystal is 3 days, and the growth time is 1 day.

Step 5: Use disposable medical sterilized tweezers to take out the single crystal. Quickly absorb the residual MAPbBr ₃ perovskite precursor solution on the surface of the single crystal with dust-free gauze. Clean the surface of the single crystal with a nitrogen gun and store it in a glove box.

The prepared MAPbBr ₃ perovskite single crystal was double-sided evaporated to process an Au electrode, and the bottom was led out with carbon glue (C) on ITO glass to prepare a longitudinal detection device. The thickness of the Au electrode was 80nm and the spacing was 1.5mm to obtain the detection device.

Comparative example 1

According to the preparation method of Example 1, a glass container was used to grow perovskite single crystal as Comparative Example 1. The preparation process was the same as that of Example 1, except that the flexible container was replaced with a glass container.

1. Analysis of single crystal morphology and growth rate

Characterize the growth rates of the single crystals of Example 1 and Comparative Example 1 under the same crystal growth conditions. The single crystal in Example 1 is recorded as a silica gel (flexible) grown single crystal, and the single crystal in Comparative Example 1 is recorded as a glass grown single crystal.

According to the scanning electron micrograph of the embodiment in Figure 1, it can be seen that the single crystal crystal of the flexible container is smooth, the surface morphology of the single crystal is good, and the size of the single crystal is 10×10×2 mm. In Figure 2, the scanning electron micrograph of the comparative example shows a glass container-grown single crystal with a rough surface and poor uniformity.

2. Single crystal quality

Characterize the crystal quality of the single crystals of Example 1 and Comparative Example 1 under the same crystal growth conditions. The single crystal in the Example is recorded as a silica gel (flexible) grown single crystal, and the single crystal in the Comparative Example is recorded as a glass grown single crystal.

(1) Single crystal surface hardness comparison

According to Figures 3 and 4, the average Vickers hardness of single crystals grown on silica gel (flexible) is 14.08, and the hardness at each point is more uniform, proving that the crystal quality and surface uniformity of the crystal are better. The average Vickers hardness of the glass-grown single crystal is 12.97, and the hardness deviation at each point is large, proving that the crystallization quality and surface uniformity of the crystal are poor.

(2) Single crystal light transmittance comparison

According to Figure 5, the transmittance of silicone (flexible) grown single crystal at a wavelength of 600-800nm is >70%, which proves that the crystal has fewer internal defects and cracks and has high transparency. The transmittance of glass-grown single crystal at a wavelength of 600-800nm is less than 30%, which proves that there are many internal defects and cracks in the crystal and the transparency is low.

(3) Single crystal carrier mobility-lifetime product comparison

According to Figure 6 and Figure 7, the carrier mobility-lifetime product of single crystal grown on silica gel (flexible) is 1.1×10 ^-3 cm ² /V, which proves that the single crystal has higher crystal quality and stronger carrier collection energy. The carrier mobility-lifetime product of glass-grown single crystal is 2.3×10 ^-4 cm ² /V, which proves that the single crystal has low crystal quality and poor carrier collection energy.

3. Optoelectronic properties

Characterize the photoelectric properties of the single crystals of Example 1 and Comparative Example 1 under the same crystal growth conditions. The single crystal in the Example is recorded as a silica gel (flexible) grown single crystal, and the single crystal in the Comparative Example is recorded as a glass grown single crystal. According to Figure 8, the photocurrent of single crystal grown on silicone (flexible) is higher, the detection switch ratio is larger, and the sensitivity of detecting X-ray photons is higher. The photocurrent of single crystal grown on glass is lower, the detection switch is relatively poor, and the sensitivity of detecting X-rays is higher. Photons are less sensitive. According to Figure 9, the full width at half maximum of the (200) crystal plane in the rocking curve test of silicone (flexible) single crystal growth reaches an extremely low 0.00529°, and the performance has reached almost the top level among the methods currently reported. According to Figure 10, the full width at half maximum of the (200) crystal plane tested by the rocking curve of the glass grown single crystal is 0.01161°, and the quality of the single crystal is obviously low.

4. Single crystal growth rate

During the single crystal growth process of Example 1 and Comparative Example 1, the single crystal growth was recorded regularly. The single crystal growth rate comparison in the two environments is shown in Figure 11. It can be seen that the time for growing single crystals on silica gel (flexible) is 4 days, and on glass. It takes 40 days to grow a single crystal, which has significant advantages in growth efficiency.

Comparative example 2

The preparation method of Example 1 was followed, but no fan was added at the bottom to guide the air flow. The crystallization position of the growing crystal is uncontrollable, the surface morphology is poor, and there is a tendency to form polycrystals. The crystallization situation is shown in Figure 12.

Comparative example 3

According to the preparation method of Example 1, the side walls are not sealed, and the single crystal nucleation sites are concentrated in the annular area at the interface between the bottom of the container and the side walls, inducing the formation and expansion of single crystal defects and cracks, and reducing the crystal quality. The crystallization situation is shown in Figure 13.

Example 2

According to the preparation method of Example 1, the precursor is dissolved at normal temperature, the dissolution time is prolonged, the nucleation sites are increased, and the average size of the single crystal is reduced.

Claims (10)

1. A method for promoting the growth of perovskite single crystals by a gas-permeable flexible container, comprising the steps of:

step 1, dissolving a perovskite raw material in an organic solvent to form a perovskite precursor liquid;

step 2, transferring the perovskite precursor liquid to a flexible container, and sealing the outlet at the top of the flexible silica gel container with polydimethylsiloxane liquid;

step 3, standing the flexible container, accelerating the airflow transmission speed at the bottom of the flexible silica gel container, and promoting the self-driven nucleation growth of perovskite single crystals in the container;

the flexible container is made of flexible materials, and the side wall is sealed by using adhesive tape.

2. The method of claim 1, wherein the flexible container comprises at least one of silica gel, rubber, latex, polyethylene, polypropylene, polyvinyl chloride, polystyrene, polyethylene terephthalate, gelatin, starch, cellulose;

and/or the organic solvent comprises at least one of gamma-butyrolactone, N-dimethylformamide and dimethyl sulfoxide.

3. The method of claim 1, wherein the perovskite precursor liquid is of the general formula a _m BX _n Wherein m is a natural number of 1 to 4, and n is a natural number of 3 to 6; in step 1, the perovskite raw material comprises AX, BX ₂ 、BX ₃ At least one of (a) and (b);

the A in the chemical general formula comprises one or more of positive monovalent lithium ions, positive monovalent sodium ions, positive monovalent potassium ions, positive monovalent cesium ions, positive monovalent rubidium ions, positive monovalent silver ions, methylamine ions, formamidine ions, phenethylamine ions, ethylamine ions, propylamine ions, butylamine ions, hexamethylenediamine ions and amantadine ions;

wherein B in the general formula comprises one or more of positive divalent lead ion, positive divalent germanium ion, positive divalent tin ion, positive trivalent aluminum ion, positive trivalent bismuth ion, positive trivalent antimony ion, positive trivalent gallium ion and positive trivalent indium ion;

and X in the chemical general formula is one or more selected from negative monovalent fluoride ions, negative monovalent chloride ions, negative monovalent bromide ions and negative monovalent iodide ions.

4. The method for promoting the growth of a perovskite single crystal by using a gas-permeable flexible container according to claim 1, wherein in the step 1, the perovskite raw material is dissolved at-30 to 20 ℃.

5. A method of promoting the growth of a single crystal perovskite according to claim 1 or claim 3, wherein the molar concentration of each perovskite raw material in the perovskite precursor solution in step 1 is 0.8 to 2.6mol/L respectively.

6. The method of claim 1, wherein the means for increasing the rate of air flow delivery comprises any one or more of a fan, an air conditioner, an oven, and an air circulator;

the adhesive tape comprises at least one of copper adhesive tape, BOPP adhesive tape, cloth-based adhesive tape, kraft paper adhesive tape, textured paper adhesive tape, fiber adhesive tape, PVC adhesive tape and PE foam adhesive tape.

7. The method for promoting the growth of perovskite single crystals by using the breathable flexible container according to claim 1, wherein the flexible container is washed with isopropanol, acetone and propanol in sequence before use and then dried.

8. The method of promoting perovskite single crystal growth by a gas permeable flexible container according to claim 1 wherein the flexible container bottom wall thickness is 1-5mm.

9. The method for promoting the growth of a perovskite single crystal by using the breathable flexible container according to claim 1, wherein the growth time of the perovskite single crystal in the step 3 is 1-9 days; and/or the thickness of the obtained perovskite single crystal is 0.1-20mm.

10. An X-ray detector comprising a perovskite single crystal obtained according to the method of any one of claims 1-9.