High-performance two-dimensional perovskite photodetector and preparation method thereof
By using the ZnO quantum dot antisolvent method in perovskite photodetectors, ZnO quantum dot/(PEA)2PbI4 nanosheet thin films were prepared, solving the problems of dark noise and lattice mismatch in photodetectors, improving photoelectric performance and stability, and achieving high photocurrent, responsivity and detectivity.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- YANGTZE DELTA REGION INST OF UNIV OF ELECTRONICS SCI & TECH OF CHINE (HUZHOU)
- Filing Date
- 2022-10-18
- Publication Date
- 2026-05-29
AI Technical Summary
Existing methods for improving the preparation of perovskite photoactive thin films suffer from lattice mismatch issues in dark noise and hybrid photoactive layers, which affect the performance of photodetectors.
The ZnO quantum dot antisolvent method was used to spin-coat a ZnO quantum dot/(PEA)2PbI4 nanosheet thin film by incorporating ZnO quantum dots into a precursor solution, followed by annealing treatment. Electrodes were then prepared by vacuum evaporation to improve carrier migration rate and photoelectric response.
This improved the photocurrent magnitude, responsivity, and detectivity of the photodetector, enhanced the stability and response time of the device, simplified the fabrication process, and improved repeatability.
Smart Images
Figure CN115835747B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of photodetector technology, and particularly relates to a high-performance two-dimensional perovskite photodetector and its fabrication method. Background Technology
[0002] Currently, perovskite, as a novel semiconductor material, has become a highly promising optoelectronic material due to its advantages such as easy solution processing, large absorption coefficient, long carrier diffusion length, and high carrier mobility.
[0003] Two-dimensional perovskites inherit the excellent photoelectric properties of three-dimensional (3D) crystals due to their closed hydrophobic organic chain spacer layers [MX6]. 4－ The protection provided by metal halide octahedrons significantly improves atmospheric stability and is considered a savior for long-term stable photodetectors based on perovskites. However, as a typical RP-phase perovskite, the van der Waals interactions between the nanosheets of (PEA)₂PbI₄ restrict charge carrier transport, posing a significant challenge to its performance compared to 3D perovskite photodetectors.
[0004] Various methods exist for preparing perovskite photoactive thin films, including chemical vapor deposition, mechanical exfoliation, and spinning. Introducing external low-dimensional materials to construct heterostructures can enhance the photoelectric response of the resulting perovskite films; or directly adding highly conductive low-dimensional materials can effectively balance fabrication simplicity and efficient charge transfer. However, this often inevitably involves complex issues such as dark noise and lattice mismatch in hybrid photoactive layers. Meanwhile, ZnO quantum dots possess advantages such as high dark resistance, high electron mobility, and a wurtzite structure. Blending ZnO quantum dots with these materials has resulted in improved film crystallinity, providing sufficient support for the fabrication of high-performance photodetectors.
[0005] Based on the above analysis, the problems and defects of the existing technology are as follows: the existing methods for preparing perovskite photoactive thin films suffer from lattice mismatch in dark noise and hybrid photoactive layers. Summary of the Invention
[0006] To address the problems existing in the prior art, this invention provides a high-performance two-dimensional perovskite photodetector and its fabrication method.
[0007] This invention is achieved as follows: A method for fabricating a high-performance two-dimensional perovskite photodetector includes:
[0008] Step 1: Clean the SiO2 glass substrate;
[0009] Step 2: Drop the precursor solution onto the surface of the glass substrate;
[0010] Step 3: Add a chloroform antisolvent solution containing ZnO quantum dots dropwise onto the precursor solution;
[0011] Step 4: Place the cleaned glass substrate on a spin coater to spin coat a ZnO quantum dot / (PEA)2PbI4 nanosheet film, and anneal the film. Repeat the above steps multiple times to obtain a uniform film.
[0012] Step 5: Gold is deposited onto the glass substrate with a uniform thin film using vacuum evaporation to obtain the electrode.
[0013] Furthermore, the precursor solution in step two is prepared as follows:
[0014] Phenethylamine iodide and PbI2 are mixed at a molar ratio of 2:1, and DMF solution is added at a concentration of 0.1 mol / L. The mixture is sonicated for at least 20 minutes and then placed in a dry environment for later use.
[0015] Furthermore, the chloroform antisolvent solution doped with ZnO quantum dots in step three is prepared by the following method:
[0016] Zinc acetate solution and potassium hydroxide solution were prepared by using zinc acetate dihydrate and KOH as solutes and methanol as solvent, respectively. The temperature was raised to 50-70℃ under continuous stirring. Then, KOH solution was added dropwise to zinc acetate solution. The mass ratio of zinc acetate dihydrate to potassium hydroxide was 1:0.4-0.5. After keeping at this temperature for 2-3 hours, the solution was allowed to cool naturally and allow ZnO quantum dots to settle under gravity. The ZnO quantum dots were then washed 2-3 times with methanol solution. Finally, the ZnO quantum dots were dispersed in chloroform solution.
[0017] Furthermore, the ZnO quantum dot concentrations in step three were 0 mg / mL, 0.032 mg / mL, 0.048 mg / mL, 0.097 mg / mL, 0.194 mg / mL, 0.388 mg / mL, and 0.776 mg / mL, respectively.
[0018] Furthermore, in step three, the volume of the precursor solution added is 100 μL, and the volume of the chloroform antisolvent solution containing the ZnO quantum dot solution added is 100 μL. After the two solutions are mixed, the reaction is allowed to proceed for 1 minute.
[0019] Furthermore, in step four, the spin coater speed is selected as 800 rpm for 20 seconds, then changed to 2000 rpm for 30 seconds.
[0020] Furthermore, in step four, the annealing temperature is 120℃ and the annealing time is 1 minute. After spin coating, anneal for 10 minutes.
[0021] Furthermore, the specific steps for cleaning the SiO2 glass substrate in step one are as follows:
[0022] Clean the oil stains on the glass surface with dish soap, then rinse the surface completely with deionized water and treat it with ultrasound. Next, soak it in ethanol and treat it with ultrasound. Finally, soak it in acetone and treat it with ultrasound. After cleaning, dry the glass substrate with nitrogen and store it.
[0023] Furthermore, the ultrasonic treatment time is 10 minutes.
[0024] Another objective of this invention is to provide a high-performance two-dimensional perovskite photodetector, which is prepared using the aforementioned method for preparing a high-performance two-dimensional perovskite photodetector.
[0025] Based on the above technical solutions and the technical problems solved, the advantages and positive effects of the technical solution to be protected by this invention are as follows:
[0026] This invention provides a method for preparing high-performance two-dimensional perovskite photodetectors based on ZnO quantum dots as an antisolvent, improving their performance and stability in the field of photodetectors. By increasing the concentration of ZnO quantum dots, the carrier migration rate is enhanced, the photocurrent is increased, and higher responsivity and detectivity are obtained, along with a shorter response time. Most perovskite solutions are very fragile and difficult to preserve under normal temperature, pressure, and humidity conditions. The antisolvent method not only obtains large-area continuous and uniform thin films, but the incorporation of ZnO quantum dots also passivates defects on the nanosheet surface, accelerates the electron transfer rate, and achieves excellent photoelectric response.
[0027] The present invention has a simple and highly repeatable manufacturing process; it features high photocurrent, high responsivity, and high detection sensitivity; it selects a suitable ZnO quantum dot concentration; it can be prepared in an air environment and has strong stability.
[0028] The zero-dimensional quantum dot / two-dimensional nanosheet perovskite photodetector provided in this application has advantages such as high stability, high photocurrent magnitude, high responsivity, and high detectivity. Attached Figure Description
[0029] Figure 1 This is a flowchart of the fabrication method of the high-performance two-dimensional perovskite photodetector provided in the embodiments of the present invention;
[0030] Figure 2 These are scanning electron microscope images of thin film surfaces provided in embodiments of the present invention;
[0031] Figure 3 This is a comparison chart of responsivity and detectivity provided in an embodiment of the present invention;
[0032] Figure 4 This is a highly stable image provided by an embodiment of the present invention. Detailed Implementation
[0033] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.
[0034] To enable those skilled in the art to fully understand how the present invention is specifically implemented, this section provides an explanatory description of the embodiments that expand upon the technical solutions of the claims.
[0035] like Figure 1 As shown, the fabrication method of the high-performance two-dimensional perovskite photodetector provided in this embodiment of the invention includes:
[0036] S101, Cleaning the SiO2 glass substrate;
[0037] S102, the precursor solution is dropped onto the surface of the glass substrate;
[0038] S103, a chloroform antisolvent solution doped with ZnO quantum dots was dropped onto the precursor solution;
[0039] S104. Place the cleaned glass substrate on a spin coater and spin coat to form a ZnO quantum dot / (PEA)2PbI4 nanosheet film. Then anneal the film and repeat the above steps multiple times to obtain a uniform film.
[0040] S105, an electrode is obtained by vacuum evaporation of gold onto a glass substrate with a uniform thin film.
[0041] The precursor solution in step S102 of this embodiment of the invention is prepared by the following method:
[0042] Phenethylamine iodide and PbI2 are mixed at a molar ratio of 2:1, and DMF solution is added at a concentration of 0.1 mol / L. The mixture is sonicated for at least 20 minutes and then placed in a dry environment for later use.
[0043] The chloroform antisolvent solution doped with ZnO quantum dots in step S103 of this embodiment of the invention is prepared by the following method:
[0044] Zinc acetate solution and potassium hydroxide solution were prepared by using zinc acetate dihydrate and KOH as solutes and methanol as solvent, respectively. The temperature was raised to 50-70℃ under continuous stirring. Then, KOH solution was added dropwise to zinc acetate solution. The mass ratio of zinc acetate dihydrate to potassium hydroxide was 1:0.4-0.5. After keeping at this temperature for 2-3 hours, the solution was allowed to cool naturally and allow ZnO quantum dots to settle under gravity. The ZnO quantum dots were then washed 2-3 times with methanol solution. Finally, the ZnO quantum dots were dispersed in chloroform solution.
[0045] In step S103 of this embodiment of the invention, the concentrations of ZnO quantum dots are 0 mg / mL, 0.032 mg / mL, 0.048 mg / mL, 0.097 mg / mL, 0.194 mg / mL, 0.388 mg / mL and 0.776 mg / mL, respectively.
[0046] In step S103 of this embodiment of the invention, the volume of the precursor solution added is 100 μL, and the volume of the chloroform antisolvent solution containing the ZnO quantum dot solution added is 100 μL. After the two solutions are mixed, the reaction is allowed to proceed for 1 minute.
[0047] In step S104 of this embodiment of the invention, the spin coater speed is selected as 800 rpm for 20 seconds, then changed to 2000 rpm for 30 seconds.
[0048] In step S104 of this embodiment of the invention, the annealing temperature is 120°C, the annealing time is 1 minute, and after spin coating, the annealing time is 10 minutes.
[0049] The specific steps for cleaning the SiO2 glass substrate in step S101 of this embodiment of the invention are as follows:
[0050] The glass surface was cleaned of oil stains with dish soap, then rinsed thoroughly with deionized water. It was then subjected to ultrasonic treatment, followed by immersion in ethanol and ultrasonic treatment, and finally immersion in acetone and ultrasonic treatment. The cleaned glass substrate was dried with nitrogen gas and then stored. The ultrasonic treatment time was 10 minutes.
[0051] The embodiments of the present invention have achieved some positive results during the research and development or use process, and have indeed great advantages compared with the prior art. The following content describes the experimental process with data, charts and other information.
[0052] Example 1:
[0053] 1) Preparation of precursor solution: Under nitrogen glove box environment, add 2 mmol (0.498 g) of PEAI granule powder and 1 mmol (0.46 g) of PbI2 powder to a glass bottle in sequence, then add 10 mL of DMF solution, and sonicate for more than 20 minutes to obtain a precursor solution with a concentration of 0.1 mol / L.
[0054] 2) Cleaning of SiO2 glass substrate: Clean the oil stains on the 2.5×2.5cm glass surface with dish soap, then rinse the surface with deionized water to remove the dish soap, and then treat it with ultrasound for 10 minutes. Next, soak it in ethanol and treat it with ultrasound for 10 minutes. Finally, soak it in acetone and treat it with ultrasound for 10 minutes. After cleaning, dry the glass substrate with nitrogen and store it.
[0055] 3) Preparation of two-dimensional perovskite thin films: A clean glass substrate was placed on a spin coater with rotation speeds of 800 r / min and 2000 r / min, and spin coating times of 20 sec and 30 sec, respectively. 100 μL of the precursor solution was first added to the glass substrate, followed by 100 μL of chloroform antisolvent solution. After the two solutions reacted for approximately 1 min, spin coating began. After spin coating, the substrate was annealed at 120 °C for 1 min. This process was repeated three times. After the final spin coating, the substrate was annealed at 120 °C for 10 min.
[0056] 4) A gold electrode with a thickness of 80 nm was deposited on the thin film surface using a vacuum evaporation method. The electrode spacing was 200 μm and the length was 8000 μm.
[0057] The perovskite photodetector prepared in this experiment was tested under the following conditions: a light source with variable wavelength and a constant optical power of 1.97 mW / m². 2 The test area is 0.016 cm². 2 The results showed that the optimal response wavelength was 500 nm, the optimal responsivity was 14.21 μA / W, and the optimal detectivity was 1.32 × 10⁻⁶. 9 Jones.
[0058] Example 2:
[0059] 1) Preparation of precursor solution: Under nitrogen glove box environment, add 2 mmol (0.498 g) of PEAI granule powder and 1 mmol (0.46 g) of PbI2 powder to a glass bottle in sequence, then add 10 mL of DMF solution, and sonicate for more than 20 minutes to obtain a precursor solution with a concentration of 0.1 mol / L.
[0060] 2) Cleaning of SiO2 glass substrate: Clean the oil stains on the 2.5×2.5cm glass surface with dish soap, then rinse the surface with deionized water to remove the dish soap, and then treat it with ultrasound for 10 minutes. Next, soak it in ethanol and treat it with ultrasound for 10 minutes. Finally, soak it in acetone and treat it with ultrasound for 10 minutes. After cleaning, dry the glass substrate with nitrogen and store it.
[0061] 3) Preparation of two-dimensional perovskite thin films doped with ZnO quantum dots: A clean glass substrate was placed on a spin coater with spin speeds set to 800 r / min and 2000 r / min, and spin coating times of 20 sec and 30 sec, respectively. 100 μL of a precursor solution was first added to the glass substrate, followed by 100 μL of a chloroform antisolvent solution containing 0.032 mg / mL ZnO quantum dots. After the two solutions reacted for approximately 1 min, spin coating began. After spin coating, the substrate was annealed at 120 °C for 1 min. This process was repeated three times, with the final spin coating followed by annealing at 120 °C for 10 min.
[0062] 4) A gold electrode with a thickness of 80 nm was deposited on the thin film surface using a vacuum evaporation method. The electrode spacing was 200 μm and the length was 8000 μm.
[0063] The perovskite photodetector prepared in this experiment was tested under the following conditions: a light source with variable wavelength and a constant optical power of 1.97 mW / m². 2 The test area is 0.016 cm². 2 The results showed that the optimal response wavelength was 500 nm, the optimal responsivity was 100.73 μA / W, and the optimal detectivity was 9.48 × 10⁻⁶. 9 Jones.
[0064] Example 3:
[0065] 1) Preparation of precursor solution: Under nitrogen glove box environment, add 2 mmol (0.498 g) of PEAI granule powder and 1 mmol (0.46 g) of PbI2 powder to a glass bottle in sequence, then add 10 mL of DMF solution, and sonicate for more than 20 minutes to obtain a precursor solution with a concentration of 0.1 mol / L.
[0066] 2) Cleaning of SiO2 glass substrate: Clean the oil stains on the 2.5×2.5cm glass surface with dish soap, then rinse the surface with deionized water to remove the dish soap, and then treat it with ultrasound for 10 minutes. Next, soak it in ethanol and treat it with ultrasound for 10 minutes. Finally, soak it in acetone and treat it with ultrasound for 10 minutes. After cleaning, dry the glass substrate with nitrogen and store it.
[0067] 3) Preparation of two-dimensional perovskite thin films doped with ZnO quantum dots: A clean glass substrate was placed on a spin coater with rotation speeds of 800 r / min and 2000 r / min, and spin coating times of 20 sec and 30 sec, respectively. First, 100 μL of a precursor solution was dropped onto the glass substrate, followed by 100 μL of a chloroform antisolvent solution containing 0.048 mg / mL ZnO quantum dots. After waiting for the two solutions to react for approximately 1 min, spin coating began. After spin coating, the substrate was annealed at 120 °C for 1 min. This process was repeated three times, with the final spin coating followed by annealing at 120 °C for 10 min.
[0068] 4) A gold electrode with a thickness of 80 nm was deposited on the thin film surface using a vacuum evaporation method. The electrode spacing was 200 μm and the length was 8000 μm.
[0069] The perovskite photodetector prepared in this experiment was tested under the following conditions: a light source with variable wavelength and a constant optical power of 1.97 mW / m. 2 The test area is 0.016 cm². 2 The results showed that the optimal response wavelength was 500 nm, the optimal responsivity was 142.40 μA / W, and the optimal detectivity was 13.50 × 10⁻⁶. 9 Jones.
[0070] Example 4:
[0071] 1) Preparation of precursor solution: Under nitrogen glove box environment, add 2 mmol (0.498 g) of PEAI granule powder and 1 mmol (0.46 g) of PbI2 powder to a glass bottle in sequence, then add 10 mL of DMF solution, and sonicate for more than 20 minutes to obtain a precursor solution with a concentration of 0.1 mol / L.
[0072] 2) Cleaning of SiO2 glass substrate: Clean the oil stains on the 2.5×2.5cm glass surface with dish soap, then rinse the surface with deionized water to remove the dish soap, and then treat it with ultrasound for 10 minutes. Next, soak it in ethanol and treat it with ultrasound for 10 minutes. Finally, soak it in acetone and treat it with ultrasound for 10 minutes. After cleaning, dry the glass substrate with nitrogen and store it.
[0073] 3) Preparation of two-dimensional perovskite thin films doped with ZnO quantum dots: A clean glass substrate was placed on a spin coater with spin speeds set to 800 r / min and 2000 r / min, and spin coating times of 20 sec and 30 sec, respectively. 100 μL of a precursor solution was first added to the glass substrate, followed by 100 μL of a chloroform antisolvent solution containing 0.097 mg / mL ZnO quantum dots. After the two solutions reacted for approximately 1 min, spin coating began. After spin coating, the substrate was annealed at 120 °C for 1 min. This process was repeated three times, with the final spin coating followed by annealing at 120 °C for 10 min.
[0074] 4) A gold electrode with a thickness of 80 nm was deposited on the thin film surface using a vacuum evaporation method. The electrode spacing was 200 μm and the length was 8000 μm.
[0075] The perovskite photodetector prepared in this experiment was tested under the following conditions: a light source with variable wavelength and a constant optical power of 1.97 mW / m. 2 The test area is 0.016 cm². 2 The results showed that the optimal response wavelength was 500 nm, the optimal responsivity was 143.94 μA / W, and the optimal detectivity was 15.40 × 10⁻⁶. 9 Jones.
[0076] Example 5:
[0077] 1) Preparation of precursor solution: Under nitrogen glove box environment, add 2 mmol (0.498 g) of PEAI granule powder and 1 mmol (0.46 g) of PbI2 powder to a glass bottle in sequence, then add 10 mL of DMF solution, and sonicate for more than 20 minutes to obtain a precursor solution with a concentration of 0.1 mol / L.
[0078] 2) Cleaning of SiO2 glass substrate: Clean the oil stains on the 2.5×2.5cm glass surface with dish soap, then rinse the surface with deionized water to remove the dish soap, and then treat it with ultrasound for 10 minutes. Next, soak it in ethanol and treat it with ultrasound for 10 minutes. Finally, soak it in acetone and treat it with ultrasound for 10 minutes. After cleaning, dry the glass substrate with nitrogen and store it.
[0079] 3) Preparation of two-dimensional perovskite thin films doped with ZnO quantum dots: A clean glass substrate was placed on a spin coater with spin speeds set to 800 r / min and 2000 r / min, and spin coating times of 20 sec and 30 sec, respectively. 100 μL of a precursor solution was first added to the glass substrate, followed by 100 μL of a chloroform antisolvent solution containing 0.194 mg / mL ZnO quantum dots. After the two solutions reacted for approximately 1 min, spin coating began. After spin coating, the substrate was annealed at 120 °C for 1 min. This process was repeated three times, with the final spin coating followed by annealing at 120 °C for 10 min.
[0080] 4) A gold electrode with a thickness of 80 nm was deposited on the thin film surface using a vacuum evaporation method. The electrode spacing was 200 μm and the length was 8000 μm.
[0081] The perovskite photodetector prepared in this experiment was tested under the following conditions: a light source with variable wavelength and a constant optical power of 1.97 mW / m. 2 The test area is 0.016 cm². 2 The results showed that the optimal response wavelength was 500 nm, the optimal responsivity was 67.45 μA / W, and the optimal detectivity was 6.82 × 10⁻⁶. 9 Jones.
[0082] Example 6:
[0083] 1) Preparation of precursor solution: Under nitrogen glove box environment, add 2 mmol (0.498 g) of PEAI granule powder and 1 mmol (0.46 g) of PbI2 powder to a glass bottle in sequence, then add 10 mL of DMF solution, and sonicate for more than 20 minutes to obtain a precursor solution with a concentration of 0.1 mol / L.
[0084] 2) Cleaning of SiO2 glass substrate: Clean the oil stains on the 2.5×2.5cm glass surface with dish soap, then rinse the surface with deionized water to remove the dish soap, and then treat it with ultrasound for 10 minutes. Next, soak it in ethanol and treat it with ultrasound for 10 minutes. Finally, soak it in acetone and treat it with ultrasound for 10 minutes. After cleaning, dry the glass substrate with nitrogen and store it.
[0085] 3) Preparation of two-dimensional perovskite thin films doped with ZnO quantum dots: A clean glass substrate was placed on a spin coater with rotation speeds of 800 r / min and 2000 r / min, and spin coating times of 20 sec and 30 sec, respectively. First, 100 μL of a precursor solution was dropped onto the glass substrate, followed by 100 μL of a chloroform antisolvent solution containing 0.388 mg / mL ZnO quantum dots. After waiting for the two solutions to react for approximately 1 min, spin coating began. After spin coating, the substrate was annealed at 120 °C for 1 min. This process was repeated three times, with the final spin coating followed by annealing at 120 °C for 10 min.
[0086] 4) A gold electrode with a thickness of 80 nm was deposited on the thin film surface using a vacuum evaporation method. The electrode spacing was 200 μm and the length was 8000 μm.
[0087] The perovskite photodetector prepared in this experiment was tested under the following conditions: a light source with variable wavelength and a constant optical power of 1.97 mW / m. 2 The test area is 0.016 cm². 2 The results showed that the optimal response wavelength was 500 nm, the optimal responsivity was 100.73 μA / W, and the optimal detectivity was 3.93 × 10⁻⁶. 9 Jones.
[0088] Example 7:
[0089] 1) Preparation of precursor solution: Under nitrogen glove box environment, add 2 mmol (0.498 g) of PEAI granule powder and 1 mmol (0.46 g) of PbI2 powder to a glass bottle in sequence, then add 10 mL of DMF solution, and sonicate for more than 20 minutes to obtain a precursor solution with a concentration of 0.1 mol / L.
[0090] 2) Cleaning of SiO2 glass substrate: Clean the oil stains on the 2.5×2.5cm glass surface with dish soap, then rinse the surface with deionized water to remove the dish soap, and then treat it with ultrasound for 10 minutes. Next, soak it in ethanol and treat it with ultrasound for 10 minutes. Finally, soak it in acetone and treat it with ultrasound for 10 minutes. After cleaning, dry the glass substrate with nitrogen and store it.
[0091] 3) Preparation of two-dimensional perovskite thin films doped with ZnO quantum dots: A clean glass substrate was placed on a spin coater with spin speeds set to 800 r / min and 2000 r / min, and spin coating times of 20 sec and 30 sec, respectively. 100 μL of a precursor solution was first added to the glass substrate, followed by 100 μL of a chloroform antisolvent solution containing 0.776 mg / mL ZnO quantum dots. After the two solutions reacted for approximately 1 min, spin coating began. After spin coating, the substrate was annealed at 120 °C for 1 min. This process was repeated three times, with the final spin coating followed by annealing at 120 °C for 10 min.
[0092] 4) A gold electrode with a thickness of 80 nm was deposited on the thin film surface using a vacuum evaporation method. The electrode spacing was 200 μm and the length was 8000 μm.
[0093] The perovskite photodetector prepared in this experiment was tested under the following conditions: a light source with variable wavelength and a constant optical power of 1.97 mW / m. 2 The test area is 0.016 cm². 2 The results showed that the optimal response wavelength was 500 nm, the optimal responsivity was 100.73 μA / W, and the optimal detectivity was 2.46 × 10⁻⁶. 9 Jones.
[0094] The embodiments of the present invention have achieved some positive results during the research and development or use process, and have indeed great advantages compared with the prior art. The following content describes the experimental process with data, charts and other information.
[0095] Figure 2 The resulting scanning electron microscope (SEM) image of the thin film surface after using this process shows a smooth thin film surface morphology.
[0096] Figure 3 This is a comparison chart of responsivity and detectivity for Examples 1 to 7.
[0097] Figure 4 The image shown is an example of an image that maintains high stability even after multiple cycle tests at 500nm.
[0098] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications, equivalent substitutions, and improvements made by those skilled in the art within the scope of the technology disclosed in the present invention, and within the spirit and principles of the present invention, should be covered within the scope of protection of the present invention.
Claims
1. A method for fabricating a high-performance two-dimensional perovskite photodetector, characterized in that, The fabrication method of the high-performance two-dimensional perovskite photodetector includes: Step 1: Clean the SiO2 glass substrate; Step 2: Drop the precursor solution onto the surface of the glass substrate; Step 3: Add a chloroform antisolvent solution containing ZnO quantum dots dropwise onto the precursor solution; Step 4: Place the cleaned glass substrate on a spin coater to spin coat a ZnO quantum dot / (PEA)2PbI4 nanosheet film, and anneal the film. Repeat the above steps multiple times to obtain a uniform film. Step 5: Gold is deposited onto the glass substrate with a uniform thin film using vacuum evaporation to obtain the electrode; The precursor solution in step two is prepared as follows: Phenethylamine iodide and PbI2 are mixed at a molar ratio of 2:1, and DMF solution is added at a concentration of 0.1 mol / L. The mixture is sonicated for at least 20 minutes and then placed in a dry environment for later use. The chloroform antisolvent solution doped with ZnO quantum dots in step three is prepared by the following method: Zinc acetate solution and potassium hydroxide solution were prepared by using zinc acetate dihydrate and KOH as solutes and methanol as solvent, respectively. The temperature was raised to 50-70℃ under continuous stirring. Then, KOH solution was added dropwise to zinc acetate solution. The mass ratio of zinc acetate dihydrate to potassium hydroxide was 1:0.4-0.
5. After keeping at this temperature for 2-3 hours, the solution was allowed to cool naturally and allow ZnO quantum dots to settle under gravity. The ZnO quantum dots were then washed 2-3 times with methanol solution. Finally, the ZnO quantum dots were dispersed in chloroform solution. In step three, the concentrations of ZnO quantum dots are: 0.032 mg / mL, 0.048 mg / mL, 0.097 mg / mL, 0.194 mg / mL, 0.388 mg / mL, or 0.776 mg / mL.
2. The method for fabricating a high-performance two-dimensional perovskite photodetector as described in claim 1, characterized in that, In step three, the volume of the precursor solution added is 100 μL, and the volume of the chloroform antisolvent solution containing the ZnO quantum dot solution added is 100 μL. After the two solutions are mixed, the reaction is allowed to proceed for 1 minute.
3. The method for fabricating a high-performance two-dimensional perovskite photodetector as described in claim 1, characterized in that, In step four, the spin coater speed is set to 800 RPM for 20 seconds, then changed to 2000 RPM for 30 seconds.
4. The method for fabricating a high-performance two-dimensional perovskite photodetector as described in claim 1, characterized in that, In step four, the annealing temperature is 120℃ and the annealing time is 1 minute. After spin coating, anneal for 10 minutes.
5. The method for fabricating a high-performance two-dimensional perovskite photodetector as described in claim 1, characterized in that, The specific steps for cleaning the SiO2 glass substrate in step one are as follows: Clean the oil stains on the glass surface with dish soap, then rinse the surface completely with deionized water and treat it with ultrasound. Next, soak it in ethanol and treat it with ultrasound. Finally, soak it in acetone and treat it with ultrasound. After cleaning, dry the glass substrate with nitrogen and store it.
6. The method for fabricating a high-performance two-dimensional perovskite photodetector as described in claim 5, characterized in that, The ultrasonic treatment time is 10 minutes.
7. A high-performance two-dimensional perovskite photodetector, characterized in that, The high-performance two-dimensional perovskite photodetector is prepared using the preparation method of the high-performance two-dimensional perovskite photodetector according to any one of claims 1 to 6.