Perovskite single crystal diode device based on spatial position defect regulation and preparation method thereof

Abstract

The invention provides a perovskite single crystal diode device based on spatial position defect regulation and a preparation method thereof. The method comprises the following steps: dropwise adding a precursor solution on a substrate layer on which metal with a high heat conductivity coefficient is deposited, and then heating to evaporate a solvent to form a perovskite single crystal layer. As the heat conductivity coefficient of the metal of the electrode layer is relatively high, the parts close to the two ends of the gold electrode in the perovskite single crystal growth process are faster in heat conduction and easy to generate more defect accumulation, and the middle overhead part is slower in heat conduction and relatively generates fewer defects, so that the regulation and control of defect distribution are realized; and a diode rectification effect of polarity reversal along with the change of a light spot position is realized on a transverse structure of a perovskite absorption layer. Structural defects are reasonably utilized, the photoelectric property of a perovskite device is flexibly regulated and controlled to expand application, the halogen vacancy defect concentration of different areas on the perovskite single crystal is regulated and controlled through the reaction temperature of the synthetic material, the overall charge transfer mechanism is changed, and the rectification characteristic that polarity can be reversed along with the change of the light spot position is achieved.

Description

Technical Field

[0001] This invention relates to the field of optoelectronic devices, and more specifically to a perovskite single-crystal diode device based on spatial position defect modulation. Background Technology

[0002] Metal halide perovskites possess advantages such as high absorption coefficients, high photoluminescence (PL) quantum efficiency, long carrier diffusion lengths, and tunable optical band gaps, leading to their wide application in solar cells, light-emitting diodes (LEDs), photodetectors, and lasers. However, due to the inherent soft lattice characteristics of perovskites, they are susceptible to various defects caused by light, humidity, and temperature, resulting in reduced performance and efficiency of perovskite optoelectronic devices. The trap density in perovskites has been shown to be strongly dependent on the material's growth and processing, leading to inconsistent results in studies of the same material. Defects in halide perovskite materials significantly affect carrier transport within the crystal lattice; therefore, the control and utilization of defects in halide perovskite materials are crucial for the development and performance improvement of perovskite-based optoelectronic devices.

[0003] Defects are inevitably introduced during the synthesis and growth of perovskite materials. Since charge carriers readily recombine at defects, or defects provide channels for ion migration leading to phase transitions, these defects significantly impact the performance, efficiency, and stability of various optoelectronic devices such as solar cells. Current solutions for handling perovskite defects can be broadly categorized as follows: 1. Defect passivation and interface engineering: Adding additives and organic / inorganic molecular layers during synthesis to passivate deep-level defects and reduce interfacial recombination, thereby improving the photoelectric conversion efficiency of solar cells and photodetectors; 2. Utilizing and controlling defects to achieve specific photoelectric properties, such as introducing shallow-level defects by doping with different ions to achieve light responses at different wavelengths.

[0004] Chinese patent CN118263372A discloses a single-layer non-heterojunction perovskite diode rectifier device. A single-crystal CsPb2Br5 device with crystal defects is fabricated using a thermal annealing method, achieving diode rectification under external power supply bias. However, this patent uses a two-dimensional (2D) layered perovskite CsPb2Br5 structure. This perovskite is an indirect bandgap semiconductor with good thermal and water-oxygen stability. This characteristic leads to a longer heating time for the precursor and a higher thermal annealing temperature during the fabrication of the CsPb2Br5 single-crystal device, making the fabrication process more complex, extending the fabrication cycle, and increasing production costs. If the reaction temperature is lower and the reaction time is insufficient, it is difficult to affect the optical and electrical properties of the perovskite, and it can still be considered an indirect bandgap semiconductor, producing no photoresponse to 405nm excitation light. Furthermore, since CsPb2Br5 is an n-type semiconductor, this device is based on Pb... 2+The shortened carrier migration length caused by vacancy defects enables diode rectification. However, this method has strict requirements on the channel distance of the planar electrode, which limits its application range and scenarios. At the same time, the carrier migration length is related to other factors such as crystal growth quality, resulting in relatively poor rectification effect and stability.

[0005] Therefore, existing methods for controlling defects are quite complex, making it impossible to flexibly control the photoelectric performance of perovskite devices and achieve polarity reversible rectification characteristics, thus limiting the application range of perovskite devices.

[0006] In conclusion, a new technical solution is urgently needed to address the problems existing in the current technology. Summary of the Invention

[0007] Based on this, the present invention involves adding a precursor solution to a substrate layer with a high thermal conductivity metal, followed by heating to evaporate the solvent, thus forming a perovskite single crystal layer. Due to the high thermal conductivity of the electrode layer metal and the formation of a channel structure, the portion near the electrode ends conducts heat faster during perovskite single crystal growth, leading to more defect accumulation. The central, suspended portion conducts heat more slowly, resulting in fewer defects, thereby achieving defect distribution control. This invention achieves defect control through a simple heating-evaporation crystallization method, realizing a diode rectification effect with polarity reversal depending on the light spot position on the lateral structure of a single perovskite absorption layer. This invention rationally utilizes structural defects to flexibly control the optoelectronic performance of perovskite devices, expanding their applications. By controlling the halogen vacancy defect concentration in different regions of the perovskite single crystal through the reaction temperature of the synthesized material, the overall charge transport mechanism is altered, achieving rectification characteristics with polarity reversal depending on the light spot position. Simultaneously, electrical and optical characterization are used to derive a reasonable physical explanation model.

[0008] One object of the present invention is to provide a perovskite single crystal diode device based on spatial position defect control, wherein the structure of the perovskite single crystal diode device based on spatial position defect control, from top to bottom, consists of a perovskite single crystal layer, an electrode layer, and a substrate layer.

[0009] in,

[0010] The raw material for the perovskite single crystal layer is a three-dimensional perovskite material;

[0011] The electrode layer is made of a metal with high thermal conductivity.

[0012] The electrode layer is deposited on the substrate layer to form a channel structure.

[0013] Furthermore, the three-dimensional perovskite material is selected from one or more of CsPbBr3 and MAPbBr3.

[0014] Preferably, the three-dimensional perovskite material is CsPbBr3. CsPbBr3 is generally orthorhombic, consisting of [PbBr6] crystals sharing vertices. 4- A three-dimensional framework composed of octahedrons, Cs + Ions fill the cubic cavities formed by the octahedral interstices, creating a three-dimensional structure. Its absorption is around 540 nm, with a band gap of approximately 2.3 eV and a high absorption coefficient, classifying it as a direct bandgap semiconductor. Furthermore, CsPbBr3 is a p-type semiconductor. The bromine vacancy defects accumulated at the electrode terminals cause band bending, generating a built-in electric field. This makes it easy for current to pass through under forward bias but difficult to pass through under reverse bias.

[0015] Furthermore, the metal with high thermal conductivity is selected from one or more of gold, chromium, and titanium.

[0016] Furthermore, the thickness of the perovskite single crystal layer is 1-5 μm.

[0017] Furthermore, the width of the channel structure is 20-40 μm.

[0018] Another object of the present invention is to provide a method for fabricating the above-mentioned perovskite single-crystal diode device based on spatial position defect modulation, comprising the following steps:

[0019] S1. Add the perovskite precursor material to a solvent, heat and stir to dissolve, and obtain a precursor solution.

[0020] S2. The precursor solution is coated onto the substrate on which the metal electrode is deposited, and the solvent is evaporated by heating to form a perovskite single crystal layer, thereby obtaining a perovskite single crystal diode device based on spatial position defect control.

[0021] Furthermore, in step S1, the perovskite precursor material includes one or more of CsBr, PbBr2, and MABr.

[0022] Furthermore, the solvent is selected from one or more of N,N-dimethylformamide (DMF), dimethyl sulfoxide, and aqueous hydrobromic acid.

[0023] Furthermore, in step S1, the heating temperature is 90-110°C.

[0024] Furthermore, in step S2, the heating temperature is 50-70°C.

[0025] The present invention has the following beneficial effects:

[0026] (1) This invention provides a perovskite single-crystal diode device based on spatial defect control. In this invention, a precursor solution is dropped onto a substrate layer with a high thermal conductivity metal, and then the solvent is evaporated by heating to form a perovskite single-crystal layer. Because the electrode layer metal has a high thermal conductivity and forms a channel structure, the portion near the electrode ends conducts heat faster during the perovskite single-crystal growth process, easily generating more defect accumulation, while the suspended portion in the middle conducts heat slower, generating relatively fewer defects, thus achieving defect distribution control. This invention achieves defect control through a simple heating-evaporation crystallization method, realizing a diode rectification effect with polarity reversal as the light spot position changes on the lateral structure of a single perovskite absorption layer.

[0027] (2) This invention makes reasonable use of structural defects and flexibly controls the photoelectric performance of perovskite devices to expand their applications. By controlling the reaction temperature of the synthesized material, the concentration of halogen vacancy defects in different regions of the three-dimensional perovskite single crystal is controlled, thereby changing the overall charge transport mechanism and realizing the rectification characteristics that can reverse polarity with the change of the spot position. At the same time, electrical and optical characterization are used to obtain a reasonable physical explanation model. Attached Figure Description

[0028] Figure 1 A schematic diagram of the fabrication of a perovskite single-crystal diode device based on spatial position defect modulation grown by thermal annealing according to an embodiment is shown.

[0029] Figure 2 The X-ray diffraction test results and visible light absorption spectra of the embodiments and comparative examples are shown;

[0030] in,

[0031] Figure 2 (a) shows the XRD patterns of the embodiments and comparative examples;

[0032] Figure 2 (b) shows the visible light absorption spectra of the embodiments and comparative examples.

[0033] Figure 3 The image shows photocurrent test plots dependent on the spot position of the embodiments and comparative examples;

[0034] in,

[0035] Figure 3 (a) shows a schematic diagram of a photocurrent spot position-dependent test;

[0036] Figure 3 (b) illustrates the spot position-dependent photocurrent of the embodiment;

[0037] Figure 3 (c) shows a proportional spot position-dependent photocurrent.

[0038] Figure 4 The photocurrent distribution of CsPbBr3 single crystal devices in the embodiments and comparative examples is shown under a bias voltage of ±1V.

[0039] in,

[0040] Figure 4 (a) shows the photocurrent distribution of the CsPbBr3 single crystal device of the embodiment under a bias voltage of ±1V;

[0041] Figure 4 (b) shows the photocurrent distribution of a comparative CsPbBr3 single crystal device under a bias voltage of ±1V.

[0042] Figure 5 The position-dependent rectification ratio in the y-direction of the CsPbBr3 single crystal device is shown in the examples and comparative examples.

[0043] Figure 6 The embodiments and comparative examples are shown in two-dimensional spatial scanning images of photoluminescence, PL spectra, and time-resolved photoluminescence images.

[0044] in,

[0045] Figure 6 (a) shows a two-dimensional spatial scanning image of the photoluminescence of the CsPbBr3 single crystal device of the embodiment;

[0046] Figure 6 (b) shows a two-dimensional spatial scanning image of photoluminescence of a CsPbBr3 single crystal device as a comparison.

[0047] Figure 6 (c) shows the PL spectrum of the CsPbBr3 single crystal device of the embodiment;

[0048] Figure 6 (d) shows the PL spectrum of a comparative CsPbBr3 single crystal device;

[0049] Figure 6 (e) shows a time-resolved photoluminescence pattern of the CsPbBr3 single crystal device of the embodiment;

[0050] Figure 6 (f) shows a time-resolved photoluminescence pattern of a comparative CsPbBr3 single crystal device.

[0051] Figure 7 The energy band diagram and charge transport mechanism schematic diagram of the CsPbBr3 single crystal device of the embodiment are shown. Detailed Implementation

[0052] To more clearly illustrate the technical solution of the present invention, the following embodiments are provided. Unless otherwise stated, the raw materials, reactions, and post-processing methods appearing in the embodiments are all commercially available raw materials and technical methods well known to those skilled in the art.

[0053] The terms "preferred," "more preferably," and "more suitable" used in this invention refer to embodiments of the invention that provide certain beneficial effects under certain circumstances. However, other embodiments may also be preferred under the same or other circumstances. Furthermore, the description of one or more preferred embodiments does not imply that other embodiments are unavailable, nor is it intended to exclude other embodiments from the scope of this invention.

[0054] It should be understood that, except in any operational instance or otherwise indicated, the amounts or all figures representing ingredients used, for example, in the specification and claims, should be understood to be modified by the term "about" in all cases. Therefore, unless otherwise stated, the numerical parameters set forth in the following specification and appended claims are approximate values ​​varying according to the desired performance to be obtained according to the invention.

[0055] Example

[0056] A perovskite single crystal diode device based on spatial position defect modulation, wherein the structure of the perovskite single crystal diode device based on spatial position defect modulation from top to bottom is: a perovskite single crystal layer (1μm), an electrode layer (150nm), and a glass substrate layer (0.5mm);

[0057] in,

[0058] The raw material for the perovskite single crystal layer is CsPbBr3;

[0059] The electrode layer is made of gold.

[0060] The electrode layer is deposited on the substrate layer to form a channel structure, and the width of the channel structure is 30 μm.

[0061] The method for fabricating the perovskite single-crystal diode device based on spatial position defect modulation includes the following steps:

[0062] S1. Mix 0.4 mmol (0.08512 g) of CsBr and 0.4 mmol (0.1468 g) of PbBr2, add to 10 mL of DMF solvent, heat and stir at 100 °C for 2 h to ensure that the solid powder is completely dissolved in DMF; then filter using a PTFE filter with a pore size of 0.22 μm to obtain a clear CsPbBr3 precursor solution.

[0063] S2. 20 μL of the CsPbBr3 precursor solution is dropped onto the glass substrate of the vapor-deposited interdigitated gold electrode, and then heated at 60°C for 15 min on a heating stage. The precursor solution evaporates and crystallizes on the glass substrate of the vapor-deposited interdigitated gold electrode to obtain a perovskite single crystal diode device based on spatial position defect control grown by thermal annealing.

[0064] Figure 1 A schematic diagram of the fabrication of a perovskite single-crystal diode device based on spatial position defect modulation grown by thermal annealing according to an embodiment is shown.

[0065] Comparative Example

[0066] A CsPbBr3 single crystal device grown by anti-solvent method has the following structure from top to bottom: perovskite single crystal layer (1μm), electrode layer (150nm), and glass substrate layer (0.5mm).

[0067] in,

[0068] The raw material for the perovskite single crystal layer is CsPbBr3;

[0069] The electrode layer is made of gold.

[0070] The electrode layer is deposited on the substrate layer to form a channel structure, and the width of the channel structure is 30 μm.

[0071] The method for fabricating CsPbBr3 single crystal devices grown by the anti-solvent method includes the following steps:

[0072] L1. Mix 0.4 mmol (0.08512 g) of CsBr and 0.4 mmol (0.1468 g) of PbBr2, add to 10 mL of DMF (N,N-dimethylformamide) solvent, heat and stir at 100 °C for 2 h to ensure that the solid powder is completely dissolved in DMF; then filter using a PTFE filter with a pore size of 0.22 μm to obtain a CsPbBr3 precursor solution.

[0073] L2. 20 μL of the CsPbBr3 precursor solution was dropped onto the substrate of the vapor-deposited gold electrode, and then evaporated at room temperature for 24 h in a sealed container filled with an anti-solvent atmosphere (methanol: dichloromethane = 1:1, v / v) to obtain the CsPbBr3 single crystal device grown by the anti-solvent method.

[0074] Test case

[0075] 1. Material characterization.

[0076] X-ray diffraction and visible light absorption spectroscopy tests were performed on the devices obtained in the examples and comparative examples. A halogen lamp provided illumination, and the transmitted light of the sample was collected through a 100x oil immersion microscope on an Olympus microscope. The signal was transmitted to an Andor spectrometer to calculate the visible light absorption spectrum of the sample.

[0077] Test results are as follows Figure 2 As shown.

[0078] Figure 2 The X-ray diffraction test results and visible light absorption spectra of the embodiments and comparative examples are shown;

[0079] in,

[0080] Figure 2 (a) shows the XRD patterns of the embodiments and comparative examples;

[0081] Figure 2 (b) shows the visible light absorption spectra of the embodiments and comparative examples.

[0082] X-ray diffraction (XRD) is a rapid, accurate, and non-destructive material detection technique widely used for phase identification of various materials. X-rays interact with materials to produce diffraction, and their distribution is related to the size, shape, and orientation of the material's unit cell, thus characterizing the crystal structure of different materials. The XRD patterns show that the main diffraction peak positions (100), (110), and (200) of the CsPbBr3 single crystal grown by thermal annealing (example) and the single crystal grown by antisolvent method (comparative example) are consistent and unchanged, matching the reported standard samples. This indicates that the single crystals grown by both methods have consistent lattice orientations, good sample purity, and no significant changes in composition. From the absorption spectra, the absorption band gaps of the crystals grown by thermal annealing (example) and antisolvent method (comparative example) are almost identical, with a cutoff at approximately 550 nm, indicating that the band gaps of the two crystals have not changed significantly.

[0083] 2. Photoelectric performance measurement.

[0084] The optoelectronic performance of the devices obtained in the examples and comparative examples was measured.

[0085] Test method: First, the center of the crystal spanning the two gold electrodes was set as the scanning zero point. Under a certain bias voltage, the crystal was scanned point by point from the anode to the cathode at intervals of 6 μm, and the photocurrent value at each point was recorded. Then, the xy-axis displacement stage was moved to perform two-dimensional planar photocurrent scanning imaging of the crystal.

[0086] Test results are as follows Figure 3-5 As shown.

[0087] Figure 3The image shows photocurrent test plots dependent on the spot position of the embodiments and comparative examples;

[0088] in,

[0089] Figure 3 (a) shows a schematic diagram of a photocurrent spot position-dependent test;

[0090] Figure 3 (b) illustrates the spot position-dependent photocurrent of the embodiment;

[0091] Figure 3 (c) shows a proportional spot position-dependent photocurrent.

[0092] The test results above show that the current distribution trends of the positive and negative electrodes of the thermally annealed CsPbBr3 single crystal device are opposite when the light spot illuminates them. This can be understood by comparing them to two back-to-back diodes. When the light spot illuminates the positive electrode, the forward bias current value is significantly greater than the reverse bias current value, further indicating that holes are the majority carriers. Measurements at different light spot positions show a clear rectification phenomenon of forward conduction and reverse cutoff in the thermally annealed CsPbBr3 single crystal sample, while the antisolvent CsPbBr3 single crystal exhibits a clearly symmetrical current distribution.

[0093] Figure 4 The photocurrent distribution of CsPbBr3 single crystal devices in the embodiments and comparative examples is shown under a bias voltage of ±1V.

[0094] in,

[0095] Figure 4 (a) shows the photocurrent distribution of the CsPbBr3 single crystal device of the embodiment under a bias voltage of ±1V;

[0096] Figure 4 (b) shows the photocurrent distribution of a comparative CsPbBr3 single crystal device under a bias voltage of ±1V.

[0097] Figure 5 The position-dependent rectification ratio in the y-direction of the CsPbBr3 single crystal device is shown in the examples and comparative examples.

[0098] Photocurrent scanning imaging (SPCM) reflects the spatial distribution of the photoelectric response of semiconductor devices. It is a powerful measurement tool for studying the defect state distribution and mechanisms of semiconductor device structures. Figure 4It can be seen that the CsPbBr3 single-crystal device in the embodiment exhibits a clear regional distribution characteristic in photocurrent distribution under a bias voltage of ±1V. Under positive bias, the photocurrent is located near the anode, while under negative bias, the photocurrent is stronger near the cathode. In contrast, the CsPbBr3 single-crystal device in the comparative example shows a significantly more uniform photocurrent distribution within the crystal, which is consistent with the results of the aforementioned spot position-dependent test, indicating that the spatial distribution of defects has a significant impact on the current transport of the device. Figure 5 It can be seen that after the spatial distribution of defects is controlled (example), the device has a rectification ratio of up to 60 times under a 4V bias voltage. The rectification ratio of the device without defect control (comparative example) is basically around 1, indicating that there is no diode rectification effect.

[0099] 3. Spatial location testing of defects.

[0100] Test method: First, an 800nm ​​femtosecond laser was used to obtain 400nm excitation light through a frequency doubling crystal. The center of the crystal, spanning the two gold electrodes, was set as the scanning zero point. The crystal was scanned point by point every 8μm from the anode to the cathode, and the photoluminescence intensity and time-resolved photoluminescence map at each point were recorded. Then, the xy-axis displacement stage was moved to perform a two-dimensional planar photoluminescence intensity scanning image of the crystal.

[0101] Test results are as follows Figure 6 As shown.

[0102] Figure 6 The embodiments and comparative examples are shown in two-dimensional spatial scanning images of photoluminescence, PL spectra, and time-resolved photoluminescence images.

[0103] in,

[0104] Figure 6 (a) shows a two-dimensional spatial scanning image of the photoluminescence of the CsPbBr3 single crystal device of the embodiment;

[0105] Figure 6 (b) shows a two-dimensional spatial scanning image of photoluminescence of a CsPbBr3 single crystal device as a comparison.

[0106] Figure 6 (c) shows the PL spectrum of the CsPbBr3 single crystal device of the embodiment;

[0107] Figure 6 (d) shows the PL spectrum of a comparative CsPbBr3 single crystal device;

[0108] Figure 6 (e) shows a time-resolved photoluminescence pattern of the CsPbBr3 single crystal device of the embodiment;

[0109] Figure 6(f) shows a time-resolved photoluminescence pattern of a comparative CsPbBr3 single crystal device.

[0110] Figure 6 (a) Figure 6 (b) is a two-dimensional spatial scanning image of photoluminescence of CsPbBr3 crystal. The photoluminescence intensity (PL) of each point on the plane is recorded by moving the x-axis and y-axis and then normalized to reflect the spatial distribution of the photoresponse of the semiconductor device. Figure 6 (c) Figure 6 (d) is the PL spectrum. Figure 6 (e) Figure 6 (f) Time-resolved photoluminescence (TRPL) was analyzed by fitting the carrier fluorescence lifetime of the material to examine the effects of defects and the carrier recombination mechanism. Following the photocurrent testing diagram above, data was recorded point-by-point from one end of the crystal to the other. The image data shows that for thermally annealed CsPbBr3 single crystals spanning the electrodes, fluorescence quenching occurs near the gold electrodes, with decreased PL intensity and shorter fluorescence lifetime, while the middle region maintains higher PL intensity and a longer fluorescence lifetime. For crystals grown using the anti-solvent method, the spatial distribution of PL intensity in different regions is relatively uniform, with no significant decrease in intensity and a relatively consistent fluorescence lifetime.

[0111] In general, the average lifetime is shorter near the electrode ends, with nonradiative recombination dominated by defect trapping. The region of significant lifetime decrease coincides well with the photocurrent region. The sharp decrease in carrier lifetime near the electrode ends is due to the influence of accumulated vacancies on the carrier recombination process. Furthermore, in CsPbBr3 crystals grown by thermal annealing, a large number of bromine vacancy defects accumulate in the gold electrode region with high thermal conductivity, while the central region has fewer defects; in CsPbBr3 crystals grown by antisolvent method, the defect spatial distribution is more uniform. Therefore, this invention achieves perovskite single-crystal devices with controllable defect distribution under temperature regulation.

[0112] 4. Theoretical model explanation.

[0113] Figure 7 The energy band diagram and charge transport mechanism schematic diagram of the CsPbBr3 single crystal device of the embodiment are shown.

[0114] Based on the experimental data above, we propose a physical theoretical explanation model. After annealing, bromine vacancy defects accumulate near both sides of the electrode. Since these are bromine vacancies, they are positively charged. The accumulated bromine vacancies cause band bending, resulting in a depletion layer and a built-in electric field. When the laser spot is focused on the positive electrode, the laser beam focuses on the sample, generating photogenerated carriers. Electrons fill the bromine vacancy defects, alleviating the band bending on one side; therefore, only the band bending on the other side needs to be considered. Under forward bias, the built-in electric field weakens, the depletion layer thins, and holes, as majority carriers, are transported across the sample to the negative electrode. Electrons near the positive electrode are collected, and the photocurrent exhibits forward conduction. Under reverse bias, the direction of the electric field is the same as the built-in electric field. The built-in electric field strengthens, the depletion layer thickens, and photogenerated electrons, under the influence of the electric field, pass through the channel and are captured by the vacancy defects accumulated near the electrode, thus exhibiting reverse cutoff.

[0115] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

[0116] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A perovskite single-crystal diode device based on spatial position defect modulation, characterized in that, The structure of the perovskite single crystal diode device based on spatial position defect modulation, from top to bottom, consists of: a perovskite single crystal layer, an electrode layer, and a substrate layer; in, The raw material for the perovskite single crystal layer is a three-dimensional perovskite material; The electrode layer is made of a metal with high thermal conductivity. The electrode layer is deposited on the substrate layer to form a channel structure.

2. The perovskite single-crystal diode device based on spatial position defect modulation according to claim 1, characterized in that, The three-dimensional perovskite material is selected from one or more of CsPbBr3 and MAPbBr3.

3. The perovskite single-crystal diode device based on spatial position defect modulation according to claim 1, characterized in that, The metal with high thermal conductivity is selected from one or more of gold, chromium, and titanium.

4. The perovskite single-crystal diode device based on spatial position defect modulation according to claim 1, characterized in that, The thickness of the perovskite single crystal layer is 1-5 μm.

5. The perovskite single-crystal diode device based on spatial position defect modulation according to claim 1, characterized in that, The width of the channel structure is 20-40 μm.

6. The method for fabricating a perovskite single-crystal diode device based on spatial position defect modulation as described in any one of claims 1-5, characterized in that, Includes the following steps: S1. Add the perovskite precursor material to a solvent, heat and stir to dissolve, and obtain a precursor solution. S2. The precursor solution is coated onto the substrate on which the metal electrode is deposited, and the solvent is evaporated by heating to form a perovskite single crystal layer, thereby obtaining a perovskite single crystal diode device based on spatial position defect control.

7. The method for fabricating a perovskite single-crystal diode device based on spatial position defect control according to claim 6, characterized in that, In step S1, the perovskite precursor material is selected from one or more of CsBr, PbBr2, and MABr.

8. The method for fabricating a perovskite single-crystal diode device based on spatial position defect control according to claim 6, characterized in that, The solvent is selected from one or more of N,N-dimethylformamide, dimethyl sulfoxide, and aqueous hydrobromic acid.

9. The method for fabricating a perovskite single-crystal diode device based on spatial position defect control according to claim 6, characterized in that, In step S1, the heating temperature is 90-110℃.

10. The method for fabricating a perovskite single-crystal diode device based on spatial position defect control according to claim 6, characterized in that, In step S2, the heating temperature is 50-70℃.

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