A method for constructing surface patterning of an organic-inorganic hybrid perovskite single crystal thin film

Abstract

The application discloses a method for constructing a surface patterning of an organic-inorganic hybrid perovskite monocrystal thin film. The method uses a compact disc track recording layer as a master, uses PDMS as a pattern transfer stamp, and adopts a liquid phase limited growth mode to realize the patterning construction on the surface of the perovskite monocrystal thin film. The finally prepared patterned perovskite monocrystal thin film has the advantages of good material crystallinity, controllable pattern size and shape, and the like, and the method is simple in process, low in cost and universally applicable to various materials. In addition, the prepared patterned organic-inorganic hybrid perovskite monocrystal thin film can be applied to a polarized photoelectric detector.

Description

Technical Field

[0001] This invention belongs to the field of patterned thin film preparation technology, and in particular, it is a method for constructing surface patterning of organic-inorganic hybrid perovskite single crystal thin films. Background Technology

[0002] Organic-inorganic hybrid perovskite materials, as an emerging semiconductor material, have been widely studied in functional devices such as photoelectric detection, solar cells, and lasers due to their advantages such as strong light absorption, tunable bandgap, long carrier lifetime, and high mobility. Despite continuous development and optimization, the numerous grain boundaries and defects within polycrystalline perovskite films inevitably lead to problems such as unnecessary recombination and scattering of carriers, IV curve hysteresis, and internal ion migration. In contrast, single-crystal perovskite films, with fewer grain boundaries and defects, exhibit higher carrier mobility, resulting in devices with superior photoelectric performance and higher stability. Surface array patterning based on single-crystal perovskite films is crucial for promoting the application of perovskite materials in polarization detection, physical anti-counterfeiting, and the integration of micro / nano optoelectronic devices.

[0003] Commonly used methods for preparing perovskite single-crystal thin films include the spatial confinement method (Nature Communications, 2017, 8(1): 1890-1896) and the wire cutting method (Journal of Materials Chemistry C 2018, 6(16): 4464-4470). The spatial confinement method restricts the growth space of the perovskite material, allowing it to grow into a specific target shape. The wire cutting method involves physical cutting and etching steps on a three-dimensional bulk single crystal to prepare perovskite material into individual single-crystal thin films.

[0004] Currently, commonly used surface patterning technologies include photolithography (Nano Letters 202020(5):3710-3717), laser direct writing (Nanoscale,2021,13:14450-14459), and stencil transfer (PhysicalChemistryChemicalPhysics,2017,19(10):7204-7214). Photolithography uses selective photoresist to prepare etching masks for target patterning and is a widely used micro-nano fabrication method. Laser direct writing uses lasers to directly act on the material surface and achieves patterning through photochemical reactions and directional ablation. Stencil transfer uses the principle of nanoimprint technology to press the target pattern onto the surface of the thin film material using a template stamp. Most existing perovskite surface patterning processes require precision instruments for pattern construction and are mostly designed for polycrystalline perovskite materials, resulting in complex processing, high costs, and poor crystallinity and stability of the obtained perovskite materials. However, no patterned construction of single-crystal thin films has been observed to date. Summary of the Invention

[0005] The purpose of this invention is to address the problems existing in the prior art by providing a method for patterning the surface of organic-inorganic hybrid perovskite single crystal thin films.

[0006] The technical solution to achieve the objective of this invention is: a method for patterning the surface of an organic-inorganic hybrid perovskite single crystal thin film, the method comprising the following steps:

[0007] Step 1: Remove the protective layer of the optical disc, rinse the organic dye on the surface of the optical track recording layer with ethanol, and then ultrasonically clean the optical track recording layer in isopropanol to obtain the grating structure template.

[0008] Step 2: Thoroughly mix the main agent and curing agent of the mixed polydimethylsiloxane PDMS, coat it onto the grating structure template, put it into a water-heated oven, and after drying, demold to obtain a PDMS template with a grating structure.

[0009] Step 3: Under a nitrogen atmosphere, add equimolar amounts of metal halide and methylamine halide dissolved in solvent and stir thoroughly to obtain an inorganic-inorganic hybrid perovskite precursor solution.

[0010] Step 4: Clean the hard substrate with deionized water, acetone, and isopropanol respectively, and dry it in a nitrogen atmosphere.

[0011] Step 5: Immerse the clean rigid substrate obtained in Step 4 in a hydrophobic solution, then remove it and let it air dry. Rinse it with anhydrous ethanol and blow it dry with nitrogen to obtain a hydrophobic rigid substrate.

[0012] Step 6: Place the hydrophobic rigid substrate on the heating stage, drop an organic-inorganic hybrid perovskite precursor solution onto it, and cover it with another hydrophobic rigid substrate inverted. Apply pressure and keep it warm for a certain period of time to grow an organic-inorganic hybrid perovskite single crystal thin film between the substrates.

[0013] Step 7: Remove the upper hydrophobic hard substrate to expose the metal halide perovskite single crystal film, press the PDMS template onto the single crystal film, and apply a certain pressure.

[0014] Step 8: Add a metal halide perovskite precursor solution to the edge of the PDMS template. The solution is drawn in by capillary action. Keep the temperature for a period of time. After the growth is completed, a surface-patterned organic-inorganic hybrid perovskite single crystal film is obtained.

[0015] Furthermore, in step 1, the optical disc is selected as a non-rewritable CD-ROM or DVD-ROM, and the ultrasonic cleaning time of the optical track recording layer is 15 min to 20 min.

[0016] Furthermore, in step 2, the mixing mass ratio of polydimethylsiloxane PDMS main agent to curing agent is 10:1, the temperature of the water-heated oven is set to 60℃, and the temperature is maintained for 8 hours.

[0017] Further, in step 3, the metal halide is lead bromide or lead iodide, the methylamine halide is methylamine iodine or methylamine bromide, and the organic-inorganic hybrid perovskite is CH3NH3PbX3, where X is a halogen element I or Br; the solvent is N,N-dimethylformamide solution DMF, the precursor solution concentration is 0.8 mol / L, the stirring temperature is 30℃, and the time is 3h.

[0018] Furthermore, the rigid substrate in step 4 is an electronic-grade glass sheet or ITO glass, and the rigid substrate is ultrasonicated with deionized water, acetone, and isopropanol for 15 min to 20 min respectively.

[0019] Furthermore, the hydrophobic solution in step 5 is obtained by adding 12 mL of dimethyldimethoxysilane and 600 μL of sulfuric acid to 200 mL of isopropanol, stirring until homogeneous, and then letting it stand for 30 min.

[0020] Furthermore, in step 6, the hydrophobic rigid substrate is pressurized at 0 kPa to 6 kPa, the temperature is set at 45°C to 55°C, and the heat preservation time is 24h to 30h.

[0021] Furthermore, in step 7, the pressure applied between the PDMS template and the hydrophobic rigid substrate ranges from 4 kPa to 14 kPa.

[0022] Furthermore, in step 8, the heat preservation temperature is 45℃~55℃, and the heat preservation time is 12h~18h.

[0023] Compared with the prior art, the significant advantages of this invention are:

[0024] 1) This invention employs a simple and low-cost method that uses the optical track recording layer of a commercially available optical disc as a master to achieve patterned construction on the surface of an organic-inorganic hybrid perovskite single crystal thin film. This avoids the complex operations and expensive equipment required by commonly used methods such as photolithography. The resulting pattern perfectly replicates the structure on the master and is applicable to various perovskite materials and different pattern constructions, thus possessing universality.

[0025] 2) The surface-patterned organic-inorganic hybrid perovskite single crystal thin film constructed in this invention inherits many excellent properties of perovskite single crystal thin films, such as fewer grain boundaries, lower internal defects, better crystallinity, etc., and has good resistance to water and oxygen erosion.

[0026] 3) The surface-patterned organic-inorganic hybrid perovskite single-crystal thin film constructed in this invention can be used to realize polarization photodetectors.

[0027] The present invention will now be described in further detail with reference to the accompanying drawings. Attached Figure Description

[0028] Figure 1 The images shown are the AFM diagram of the CD-ROM optical disc recording layer surface pattern and the cross-sectional height distribution diagram of the channel pattern in Embodiment 1 of the present invention. Figure 1 (a) is an AFM image. Figure 1 (b) is a diagram showing the height distribution of the cross-section of the channel pattern.

[0029] Figure 2 The images shown are AFM and SEM images of the PDMS-CD template surface in Embodiment 1 of the present invention. Figure 2 (a) is an AFM image. Figure 2 (b) is the SEM image.

[0030] Figure 3 This is a SEM image of the surface of the CH3NH3PbBr3 single crystal thin film after surface patterning using a PDMS-CD template in Embodiment 1 of the present invention.

[0031] Figure 4 The images shown are AFM images of the patterned perovskite single-crystal thin film surface prepared in Example 1 of this invention, and a cross-sectional height distribution diagram of its channel pattern. Figure 4 (a) is an AFM image. Figure 4 (b) is a diagram showing the height distribution of the cross-section of the channel pattern.

[0032] Figure 5 This is an X-ray diffraction pattern of the CH3NH3PbBr3 single crystal thin film after surface patterning using a PDMS-CD template in Embodiment 1 of the present invention.

[0033] Figure 6 The images shown are AFM images of the PDMS-DVD template surface and a cross-sectional height distribution diagram of the channel pattern in Embodiment 2 of the present invention. Figure 6 (a) is an AFM image. Figure 6 (b) is a diagram showing the height distribution of the cross-section of the channel pattern.

[0034] Figure 7 The images shown are AFM and SEM images of the PDMS-DVD template surface in Embodiment 2 of the present invention. Figure 7 (a) is an AFM image. Figure 7 (b) is the SEM image.

[0035] Figure 8 This is a SEM image of the surface of the CH3NH3PbBr3 single crystal thin film after surface patterning using a PDMS-DVD template in Embodiment 2 of the present invention.

[0036] Figure 9 The images shown are AFM images of the patterned CH3NH3PbBr3 single crystal thin film surface prepared in Example 2 of this invention, and a cross-sectional height distribution diagram of its channel pattern. Figure 9 (a) is an AFM image. Figure 9 (b) is a diagram showing the height distribution of the cross-section of the channel pattern.

[0037] Figure 10 This is an X-ray diffraction pattern of the CH3NH3PbBr3 single crystal thin film after surface patterning using a PDMS-CD template in Embodiment 2 of the present invention.

[0038] Figure 11 The images shown are AFM images of the patterned CH3NH3PbI3 single crystal thin film surface prepared in Example 3 of this invention, and a cross-sectional height distribution diagram of its channel pattern. Figure 11 (a) is an AFM image. Figure 11 (b) is a diagram showing the height distribution of the cross-section of the channel pattern.

[0039] Figure 12 This is a SEM image of the surface of the CH3NH3PbI3 single crystal thin film after surface patterning using a PDMS-CD template in Embodiment 3 of the present invention.

[0040] Figure 13 This is an X-ray diffraction pattern of the CH3NH3PbI3 single crystal thin film after surface patterning using a PDMS-CD template in Embodiment 3 of the present invention.

[0041] Figure 14 The IV curve is the patterned CH3NH3PbBr3 single-crystal thin-film photodetector constructed in Embodiment 4 of the present invention.

[0042] Figure 15 The EQE diagram is shown for the patterned CH3NH3PbBr3 single-crystal thin-film photodetector constructed in Embodiment 4 of the present invention. Detailed Implementation

[0043] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0044] This invention proposes a method for surface patterning of organic-inorganic hybrid perovskite single-crystal thin films, the method comprising the following steps:

[0045] Step 1: Remove the protective layer of the optical disc, rinse the organic dye on the surface of the optical track recording layer with ethanol, and then ultrasonically clean the optical track recording layer in isopropanol to obtain the grating structure template.

[0046] Step 2: Thoroughly mix the main agent and curing agent of the mixed polydimethylsiloxane PDMS, coat it onto the grating structure template, put it into a water-heated oven, and after drying, demold to obtain a PDMS template with a grating structure.

[0047] Step 3: Under a nitrogen atmosphere, add equimolar amounts of metal halide and methylamine halide dissolved in solvent and stir thoroughly to obtain an inorganic-inorganic hybrid perovskite precursor solution.

[0048] Step 4: Clean the hard substrate with deionized water, acetone, and isopropanol respectively, and dry it in a nitrogen atmosphere.

[0049] Step 5: Immerse the clean rigid substrate obtained in Step 4 in a hydrophobic solution, then remove it and let it air dry. Rinse it with anhydrous ethanol and blow it dry with nitrogen to obtain a hydrophobic rigid substrate.

[0050] Step 6: Place the hydrophobic rigid substrate on the heating stage, drop an organic-inorganic hybrid perovskite precursor solution onto it, and cover it with another hydrophobic rigid substrate inverted. Apply pressure and keep it warm for a certain period of time to grow an organic-inorganic hybrid perovskite single crystal thin film between the substrates.

[0051] Step 7: Remove the upper hydrophobic hard substrate to expose the metal halide perovskite single crystal film, press the PDMS template onto the single crystal film, and apply a certain pressure.

[0052] Step 8: Add a metal halide perovskite precursor solution to the edge of the PDMS template. The solution is drawn in by capillary action. Keep the temperature for a period of time. After the growth is completed, a surface-patterned organic-inorganic hybrid perovskite single crystal film is obtained.

[0053] The present invention will now be described in further detail with reference to specific embodiments.

[0054] Example 1

[0055] This embodiment describes a method for patterning a CH3NH3PbBr3 single-crystal thin film surface, specifically including the following steps:

[0056] Step 1: Cut the CD-ROM disc into 1cm×1cm squares, stick them with transparent tape and peel off the disc's protective layer. Place the exposed optical track recording layer in anhydrous ethanol to rinse off the green organic dye on the surface, and sonicate for 15 minutes. After removing it, blow it dry with nitrogen to obtain a master plate with linear grooves.

[0057] Step 2: Weigh 10g of PDMS main agent, add 1g of curing agent, stir thoroughly, and then apply it to the optical disc track recording layer. Then place it in a water-heated oven, keep it at 60℃ for 8 hours to cure, and then demold to obtain a PDMS-CD template with a linear groove structure printed on the optical disc track recording layer.

[0058] Step 3: In a nitrogen atmosphere, take 0.08957g CH3NH3Br and 0.2936g PbBr2 and place them in a 4ml reagent bottle. Add 1ml of DMF as a solvent to the bottle and stir at 30℃ for 180min using a magnetic stirrer to obtain a CH3NH3PbBr3 precursor solution with a concentration of 0.8mol / L.

[0059] Step 4: Add 12 ml of dimethyldimethoxysilane and 600 μL of sulfuric acid to 200 ml of isopropanol, stir well, and let stand for 30 min to obtain a hydrophobic solution.

[0060] Step 5: Take a 5cm×5cm electronic-grade glass slide, and place it in cleaning agent, deionized water, acetone and isopropanol in sequence, sonicate for 15 minutes each, then soak it in a hydrophobic solution, take it out and let it air dry, rinse the substrate with ethanol and blow it dry in nitrogen to obtain a hydrophobic substrate.

[0061] Step 6: Place the hydrophobic substrate on the heating stage, add 125 μL of CH3NH3PbBr3 precursor solution, and cover it with another hydrophobic substrate inverted. Apply pressure of 6 kPa and maintain at 50°C for 24 h to grow CH3NH3PbBr3 single crystal thin film.

[0062] Step 7: Open the upper hydrophobic substrate, press the PDMS-CD template onto the CH3NH3PbBr3 single crystal thin film, and apply a pressure of 14 kPa to it.

[0063] Step 8: Drop 5 μL of CH3NH3PbBr3 precursor solution onto the edge of the PDMS template. The solution is then drawn into the gap between the template and the single crystal by capillary action. Keep the solution at 50°C for 12 h. After growth, remove the solution to obtain a patterned CH3NH3PbBr3 single crystal film.

[0064] The prepared product was then analyzed and characterized, such as... Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 As shown. The results show that, according to the method of Example 1, the surface pattern of the CD optical disc recording layer can be completely copied onto the surface of the CH3NH3PbBr3 single crystal thin film to achieve surface patterning, and no obvious defects are observed. The surface patterned structure is a groove array structure with a height of 200 nm and a periodic distribution of 1600 nm spacing. The XRD pattern shows that the crystal quality of the CH3NH3PbBr3 single crystal thin film after surface patterning is high.

[0065] Example 2

[0066] This embodiment describes a method for patterning a CH3NH3PbBr3 single-crystal thin film surface, specifically including the following steps:

[0067] Step 1: Cut the DVD-ROM disc into 1cm×1cm squares, stick them with transparent tape and peel off the disc's protective layer. Place the exposed optical track recording layer in anhydrous ethanol to rinse off the purple organic dye on the surface, and sonicate for 15 minutes. After removing it, blow it dry with nitrogen to obtain a master plate with linear grooves.

[0068] Step 2: Weigh 10g of PDMS main agent, add 1g of curing agent, stir thoroughly, and then apply it to the optical disc track recording layer. Then place it in a water-heated oven, keep it at 60℃ for 8 hours to cure, and then demold to obtain a PDMS-DVD template with a linear groove structure printed on the optical disc track recording layer.

[0069] Step 3: In a nitrogen atmosphere, take 0.08957g CH3NH3Br and 0.2936g PbBr2 and place them in a 4ml reagent bottle. Add 1ml of DMF as a solvent to the bottle and stir at 30℃ for 180min using a magnetic stirrer to obtain a CH3NH3PbBr3 precursor solution with a concentration of 0.8mol / L.

[0070] Step 4: Add 12 ml of dimethyldimethoxysilane and 600 μL of sulfuric acid to 200 ml of isopropanol, stir well and let stand for 30 min to obtain a hydrophobic solution;

[0071] Step 5: Take a 5cm×5cm electronic-grade glass slide, and place it in cleaning agent, deionized water, acetone and isopropanol in sequence, sonicate for 15 minutes each, then soak it in a hydrophobic solution, take it out and let it air dry, rinse the substrate with ethanol and blow it dry in nitrogen to obtain a hydrophobic substrate.

[0072] Step 6: Place the hydrophobic substrate on the heating stage, add 125 μL of CH3NH3PbBr3 precursor solution, and cover it with another hydrophobic substrate inverted. Apply pressure of 6 kPa and maintain at 50°C for 24 h to grow CH3NH3PbBr3 single crystal thin film.

[0073] Step 7: Open the upper hydrophobic substrate, press the PDMS-DVD template onto the CH3NH3PbBr3 single crystal thin film, and apply a pressure of 14 kPa to it;

[0074] Step 8: Drop 5 μL of CH3NH3PbBr3 precursor solution onto the edge of the PDMS template. The solution is then drawn into the gap between the template and the single crystal by capillary action. Keep the solution at 50°C for 12 h. After growth, remove the solution to obtain a patterned CH3NH3PbBr3 single crystal film.

[0075] The prepared product was then analyzed and characterized, such as... Figure 6 , Figure 7 , Figure 8 , Figure 9 , Figure 10 As shown. The results show that, according to the method of Example 2, the surface pattern of the DVD disc recording layer can be completely copied onto the surface of the CH3NH3PbBr3 single crystal thin film. The surface patterned structure is a groove array structure with a height of 100 nm and a periodic distribution of 750 nm spacing. The XRD pattern shows that the crystal quality of the CH3NH3PbBr3 single crystal thin film is still high after surface patterning.

[0076] Example 3

[0077] This embodiment describes a method for patterning a CH3NH3PbI3 single-crystal thin film, specifically including the following steps:

[0078] Step 1: Cut the CD-ROM disc into 1cm×1cm squares, stick them with transparent tape and peel off the disc's protective layer. Place the exposed optical track recording layer in anhydrous ethanol to rinse off the green organic dye on the surface, and sonicate for 15 minutes. After removing it, blow it dry with nitrogen to obtain a master plate with linear grooves.

[0079] Step 2: Weigh 10g of PDMS main agent, add 1g of curing agent, stir thoroughly, and then apply it to the optical disc track recording layer. Then place it in a water-heated oven, keep it at 60℃ for 8 hours to cure, and then demold to obtain a PDMS-CD template with a linear groove structure printed on the optical disc track recording layer.

[0080] Step 3: In a nitrogen atmosphere, take 0.1271g CH3NH3I and 0.3688g PbI2 and place them in a 4ml reagent bottle. Add 1ml of DMF as a solvent to the bottle and stir at 30℃ for 180min using a magnetic stirrer to obtain a CH3NH3PbI3 precursor solution with a concentration of 0.8mol / L.

[0081] Step 4: Add 12 ml of dimethyldimethoxysilane and 600 μL of sulfuric acid to 200 ml of isopropanol, stir well and let stand for 30 min to obtain a hydrophobic solution;

[0082] Step 5: Take a 5cm×5cm electronic-grade glass slide, and place it in cleaning agent, deionized water, acetone and isopropanol in sequence, sonicate for 15 minutes each, then soak it in a hydrophobic solution, take it out and let it air dry, rinse the substrate with ethanol and blow it dry in nitrogen to obtain a hydrophobic substrate.

[0083] Step 6: Place the hydrophobic substrate on the heating stage, add 125 μL of CH3NH3PbI3 precursor solution, and cover it with another hydrophobic substrate inverted. Apply pressure of 6 kPa and maintain at 50°C for 24 h to grow CH3NH3PbBr3 single crystal thin film.

[0084] Step 7: Open the upper hydrophobic substrate, press the PDMS-CD template onto the CH3NH3PbI3 single crystal thin film, and apply a pressure of 14 kPa to it;

[0085] Step 8: Drop 5 μL of CH3NH3PbI3 precursor solution onto the edge of the PDMS template. The solution is then drawn into the gap between the template and the single crystal by capillary action. Keep the solution at 50°C for 12 h. After growth, remove the solution to obtain a patterned CH3NH3PbI3 single crystal film.

[0086] The prepared product was then analyzed and characterized, such as... Figure 11 , Figure 12 , Figure 13 As shown. The results show that, following the method of Example 3, a complete replication of the CD optical disc recording layer surface pattern on the CH3NH3PbI3 single crystal thin film was achieved. No obvious defects were observed in the SEM image, and the XRD pattern shows that the CH3NH3PbI3 single crystal thin film still retains a near-single crystal quality after surface patterning.

[0087] Example 4

[0088] This embodiment describes a method for patterning and fabricating a photodetector on the surface of a CH3NH3PbBr3 single-crystal thin film, specifically including the following steps:

[0089] Step 1: Cut the CD-ROM disc into 1cm×1cm squares, stick them with transparent tape and peel off the disc's protective layer. Place the exposed optical track recording layer in anhydrous ethanol to rinse off the green organic dye on the surface, and sonicate for 15 minutes. After removing it, blow it dry with nitrogen to obtain a master plate with linear grooves.

[0090] Step 2: Weigh 10g of PDMS main agent, add 1g of curing agent, stir thoroughly, and then apply it to the optical disc track recording layer. Then place it in a water-heated oven, keep it at 60℃ for 8 hours to cure, and then demold to obtain a PDMS-CD template with a linear groove structure printed on the optical disc track recording layer.

[0091] Step 3: In a nitrogen atmosphere, take 0.08957g CH3NH3Br and 0.2936g PbBr2 and place them in a 4ml reagent bottle. Add 1ml of DMF as a solvent to the bottle and stir at 30℃ for 180min using a magnetic stirrer to obtain a CH3NH3PbBr3 precursor solution with a concentration of 0.8mol / L.

[0092] Step 4: Add 12 ml of dimethyldimethoxysilane and 600 μL of sulfuric acid to 200 ml of isopropanol, stir well and let stand for 30 min to obtain a hydrophobic solution;

[0093] Step 5: Take a 3cm×3cm ITO electrode glass with a channel of 50μm, put it into cleaning agent, deionized water, acetone and isopropanol in sequence and sonicate for 15min each. Then soak it in a hydrophobic solution, take it out and let it dry naturally. Rinse the substrate with ethanol and blow it dry in nitrogen to obtain a hydrophobic ITO substrate.

[0094] Step 6: Place the hydrophobic ITO substrate on the heating stage, add 125 μL of CH3NH3PbBr3 precursor solution, and cover it with another hydrophobic ITO substrate. Apply pressure of 6 kPa and maintain at 50°C for 24 h to grow CH3NH3PbBr3 single crystal thin film.

[0095] Step 7: Open the upper hydrophobic substrate, select a CH3NH3PbBr3 single crystal thin film that is in contact with both ITO electrodes, press the PDMS-CD template on it, and apply a pressure of 14 kPa to it.

[0096] Step 8: Drop 5 μL of CH3NH3PbBr3 precursor solution onto the edge of the PDMS template. The solution is then drawn into the gap between the template and the single crystal by capillary action. Keep the solution at 50°C for 12 hours. After growth, remove the solution to obtain a photodetector based on a patterned CH3NH3PbBr3 single crystal thin film.

[0097] The prepared photodetector was then characterized by electrical analysis, such as... Figure 14 , Figure 15 As shown in the figure, the results demonstrate that a photodetector based on a patterned CH3NH3PbBr3 single-crystal thin film was successfully fabricated according to the method described in Example 4. The figure shows that this detector exhibits significant photoresponse characteristics, responding to light in the 300nm-560nm range, and achieving an external quantum efficiency as high as 42% under a 3V bias voltage.

[0098] The patterned perovskite single-crystal thin films prepared by this invention have advantages such as good material crystallinity and controllable pattern size and shape. Furthermore, the process is simple, low-cost, and widely applicable to various materials. In addition, the resulting patterned organic-inorganic hybrid perovskite single-crystal thin films can be used in polarization photodetectors.

[0099] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention without departing from its spirit and scope should be included within the protection scope of the present invention.

Claims

1. A method for patterning the surface of an organic-inorganic hybrid perovskite single-crystal thin film, characterized in that, The method includes the following steps: Step 1: Remove the protective layer of the optical disc, rinse the organic dye on the surface of the optical track recording layer with ethanol, and then ultrasonically clean the optical track recording layer in isopropanol to obtain the grating structure template. Step 2: Thoroughly mix the main agent and curing agent of the mixed polydimethylsiloxane PDMS, coat it onto the grating structure template, put it into a water-heated oven, and after drying, demold to obtain a PDMS template with a grating structure. Step 3: Under a nitrogen atmosphere, add equimolar amounts of metal halide and methylamine halide dissolved in solvent and stir thoroughly to obtain an inorganic-inorganic hybrid perovskite precursor solution. Step 4: Clean the hard substrate with deionized water, acetone, and isopropanol respectively, and dry it in a nitrogen atmosphere. Step 5: Immerse the clean rigid substrate obtained in Step 4 in a hydrophobic solution, then remove it and let it air dry. Rinse it with anhydrous ethanol and blow it dry with nitrogen to obtain a hydrophobic rigid substrate. Step 6: Place the hydrophobic rigid substrate on the heating stage, drop an organic-inorganic hybrid perovskite precursor solution onto it, and cover it with another hydrophobic rigid substrate inverted. Apply pressure and keep it warm for a certain period of time to grow an organic-inorganic hybrid perovskite single crystal thin film between the substrates. Step 7: Remove the upper hydrophobic hard substrate to expose the metal halide perovskite single crystal film, press the PDMS template onto the single crystal film, and apply a certain pressure. Step 8: Add a metal halide perovskite precursor solution to the edge of the PDMS template. The solution is drawn in by capillary action. Keep the temperature for a period of time. After the growth is completed, a surface-patterned organic-inorganic hybrid perovskite single crystal film is obtained.

2. The method for surface patterning of organic-inorganic hybrid perovskite single crystal thin films according to claim 1, characterized in that, In step 1, non-rewritable CD-ROMs and DVD-ROMs are selected for optical discs, and the ultrasonic cleaning time for the optical track recording layer is 15 min to 20 min.

3. The method for surface patterning of organic-inorganic hybrid perovskite single crystal thin films according to claim 1, characterized in that, In step 2, the mixing mass ratio of polydimethylsiloxane (PDMS) main agent to curing agent is 10:1, the water-heated oven temperature is set to 60℃, and the temperature is maintained for 8 hours.

4. The method for surface patterning of organic-inorganic hybrid perovskite single crystal thin films according to claim 1, characterized in that, The metal halide mentioned in step 3 is lead bromide or lead iodide, the methylamine halide is methylamine iodine or methylamine bromide, and the organic-inorganic hybrid perovskite is CH3NH3PbX3, where X is a halogen element I or Br; the solvent is N,N-dimethylformamide solution DMF, the precursor solution concentration is 0.8 mol / L, the stirring temperature is 30℃, and the time is 3h.

5. The method for surface patterning of organic-inorganic hybrid perovskite single crystal thin films according to claim 1, characterized in that, The rigid substrate in step 4 is an electronic-grade glass sheet or ITO glass. The rigid substrate is ultrasonicated with deionized water, acetone, and isopropanol for 15 to 20 minutes respectively.

6. The method for surface patterning of organic-inorganic hybrid perovskite single crystal thin films according to claim 1, characterized in that, The hydrophobic solution in step 5 was obtained by adding 12 mL of dimethyldimethoxysilane and 600 μL of sulfuric acid to 200 mL of isopropanol, stirring until homogeneous, and then letting it stand for 30 min.

7. The method for surface patterning of organic-inorganic hybrid perovskite single crystal thin films according to claim 1, characterized in that, In step 6, the hydrophobic rigid substrate is pressurized at 0 kPa to 6 kPa, the temperature is set at 45℃ to 55℃, and the heat preservation time is 24h to 30h.

8. The method for surface patterning of organic-inorganic hybrid perovskite single crystal thin films according to claim 1, characterized in that, In step 7, the pressure applied between the PDMS template and the hydrophobic rigid substrate ranges from 4 kPa to 14 kPa.

9. The method for surface patterning of organic-inorganic hybrid perovskite single crystal thin films according to claim 1, characterized in that, In step 8, the heat preservation temperature is 45℃~55℃, and the heat preservation time is 12h~18h.

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