Self-powered photodetector based on one-dimensional and three-dimensional hybrid perovskite ferroelectric film / P3HT heterojunction and its preparation method

Abstract

The present invention provides a self-powered photodetector based on a one-dimensional and three-dimensional hybrid perovskite ferroelectric film / P3HT heterojunction and a preparation method thereof. The self-powered photodetector provided by the present invention comprises, from bottom to top, a conductive substrate layer, a one-dimensional and three-dimensional hybrid perovskite ferroelectric film layer, a P3HT layer and a metal top electrode layer. The present invention realizes self-powered light detection by constructing a self-powered photodetector based on a one-dimensional and three-dimensional hybrid perovskite ferroelectric film / poly (3-hexylthiophene) heterojunction and utilizing the ferroelectric-pyroelectric optoelectronic effect of the one-dimensional and three-dimensional hybrid perovskite ferroelectric film. The present invention can solve the problem in the prior art that three-dimensional metal halide perovskite photodetectors rely on external power supply. The one-dimensional and three-dimensional hybrid perovskite ferroelectric film in the present invention has the advantages of high quality and good stability, and can be prepared into a flexible photodetector with good mechanical flexibility.

Description

Technical Field

[0001] The present invention relates to the technical field of photoelectric detectors, and in particular to a self-powered photoelectric detector based on a one-dimensional and three-dimensional mixed perovskite ferroelectric film / P3HT heterojunction and a preparation method thereof. Background Art

[0002] Photodetectors play a vital role in military detection, environmental monitoring, life sciences, flame warning, and aerospace. Photodetectors are primarily based on semiconductor materials such as GaN, Si, and InGaAs. However, practical applications still face challenges such as demanding preparation conditions and high costs. In recent years, three-dimensional metal halide perovskites, due to their excellent properties, have become ideal materials for constructing photodetectors. However, these materials suffer from limitations such as poor stability and the need for external power supply, significantly hindering their practical applications. Recently, the team of Academician Wang Zhonglin proposed the concept of the pyroelectric photoelectric effect, a ternary coupling effect based on the semiconductor-photoexcitation-pyroelectric properties. This effect utilizes the pyroelectric polarization charge generated by illumination to modulate the interfacial band structure of a pn or Schottky junction, thereby regulating the generation, separation, transport, and recombination of carriers, enabling highly sensitive, self-powered photodetection. However, to date, research on self-powered photodetectors based on the pyroelectric photoelectric effect remains limited. Summary of the Invention

[0003] The purpose of the present invention is to provide a self-powered photodetector based on a one-dimensional and three-dimensional hybrid perovskite ferroelectric film / P3HT heterojunction and a preparation method thereof. The present invention utilizes the pyroelectric photoelectronic effect of the one-dimensional and three-dimensional hybrid perovskite ferroelectric film material to achieve self-powered light detection; the preparation method of the photodetector is simple and low in cost.

[0004] The present invention is achieved in that:

[0005] A self-powered photodetector based on a 1D / 3D hybrid perovskite ferroelectric film / P3HT heterojunction consists, from bottom to top, of a conductive substrate, a 1D / 3D hybrid perovskite ferroelectric film layer (which also serves as a light-absorbing layer), a P3HT layer, and a metal top electrode layer. The 1D / 3D hybrid perovskite ferroelectric film is prepared by heated spin coating. After further cleaning and repair, the resulting film is low in defects and highly stable.

[0006] Furthermore, in the one-dimensional and three-dimensional mixed perovskite ferroelectric film, the one-dimensional metal halide perovskite is TMIMPbI3[(CH3)3NCH2IPbI3, (iodomethyl)trimethylammonium lead iodide], and the three-dimensional metal halide perovskite is MAPbI3(CH3NH3PbI3, methylammonium lead iodide), FA x MA y Cs1-x-y PbI3 (0 < x < 1, 0 < y < 1, x + y < 1), MA x Cs 1-x Any one of PbI3 (0 < x < 1). TMIM refers to (iodomethyl) trimethylammonium, MA refers to methylammonium, and FA refers to formamidine.

[0007] In a preferred embodiment, the specific preparation process of the one-dimensional and three-dimensional hybrid perovskite ferroelectric thin film is as follows:

[0008] 1) Prepare the perovskite precursor solution: Add a lead salt with a molar ratio of 9:1 of 0.5 - 0.6 M PbI2 (lead iodide) and Pb(SCN)2 (lead thiocyanate), 0.5 - 0.6 M iodide cation salt (such as MAI, CsI, FAI), and 3 - 3.6 mM TMIMI [(iodomethyl) trimethylammonium iodide] to MAAc (methylacetamide), and stir at 50 - 60 °C for 10 - 12 h. Further add a 1,3 - diamino propane (1,3 - DAP) solution with a mass fraction of 0.02 - 0.025 wt% to the above solution to obtain the perovskite precursor solution.

[0009] 2) Preparation of the one-dimensional and three-dimensional hybrid perovskite ferroelectric thin film: Fix a clean and hydrophilized conductive substrate with a size of 1×1 cm 2 - 5×5 cm 2 on a heating spin coater, heat to 90 - 100 °C and keep it constant. Take 20 - 25 μL of the perovskite precursor solution and drop it onto the conductive substrate, and spin coat at a speed of 4000 rpm for 20 - 30 s. Anneal at 60 - 65 °C and 100 - 110 °C for 1 - 5 min and 1 - 5 min respectively to obtain the one-dimensional and three-dimensional hybrid perovskite ferroelectric thin film. To reduce the defects of the material and improve the stability of the thin film, further perform surface cleaning on the thin film with a mixed solution of cyclohexane and tert-amyl alcohol with a volume ratio of 4:1, and then repair it with a mixed solution of 0.2 - 0.3 mg / mL MAI and 0.2 - 0.3 mg / mL TEA (tetraethylammonium iodide) to obtain a one-dimensional and three-dimensional hybrid perovskite ferroelectric thin film with low defects and high stability.

[0010] 3) Spin coat P3HT in a chlorobenzene solution (10 - 15 mg / mL) onto the one-dimensional and three-dimensional hybrid perovskite ferroelectric thin film with low defects and high stability to obtain a one-dimensional and three-dimensional hybrid perovskite ferroelectric thin film / P3HT heterojunction.

[0011] In a preferred embodiment, the thickness of the one-dimensional and three-dimensional hybrid perovskite ferroelectric thin film is 450 - 550 nm.

[0012] In a preferred embodiment, the purity of MAAc is not less than 99.99%.

[0013] In a preferred embodiment, the substrate is an ITO rigid substrate or an ITO / PEN flexible substrate.

[0014] In a more preferred embodiment, the conductive substrate is first soaked in a 0.4 wt% PEIE aqueous solution for 30 seconds before sample preparation, then washed in deionized water for 3 seconds, and finally thermally annealed at 100° C. for 10 minutes to improve the wettability of the substrate to MAAc.

[0015] This invention proposes a self-powered photodetector based on a one-dimensional, three-dimensional hybrid perovskite ferroelectric film / P3HT (poly (3-hexylthiophene)) heterojunction. The device is simple and inexpensive to prepare, requiring only simple methods such as chemical synthesis to produce the ferroelectric film. Further cleaning and repair of the one-dimensional, three-dimensional hybrid perovskite ferroelectric film significantly reduces film defects and improves film stability. By constructing a self-powered photodetector based on a one-dimensional, three-dimensional hybrid perovskite ferroelectric film / poly (3-hexylthiophene) heterojunction, the invention utilizes the ferroelectric-pyroelectric optoelectronic effect of the one-dimensional, three-dimensional hybrid perovskite ferroelectric film to achieve self-powered optical detection.

[0016] Compared with the prior art, the advantages of the present invention are:

[0017] 1. The one-dimensional and three-dimensional hybrid perovskite ferroelectric thin film prepared by the present invention has a uniform surface free of pinholes and high crystalline quality, as shown by scanning electron microscopy (SEM) and X-ray diffraction (XRD) patterns. Furthermore, the film is prepared in a single step using a heated spin coating method, simplifying the preparation process.

[0018] 2. This invention utilizes the ferroelectric-pyroelectric photoelectric effect of a one-dimensional (1D) and three-dimensional (3D) hybrid perovskite ferroelectric thin film to achieve self-powered photodetection. The key principle is that, under zero bias, in the dark, the one-dimensional (3D) hybrid perovskite ferroelectric film spontaneously polarizes along the normal direction, generating positive charges at the perovskite-ITO interface and negative charges at the pn junction interface. Consequently, opposite free charges are generated in the ITO electrode and P3HT. Upon laser irradiation, photoinduced carriers are generated and separated by the pn junction and the ferroelectrically induced built-in electric field, generating a photocurrent. Furthermore, due to increased thermal vibrations, the light-induced temperature rise disrupts the random oscillations of the electric dipoles in the one-dimensional (3D) hybrid perovskite film, resulting in a reduction in the ferroelectric polarization charge. Consequently, the free charge flow generates a positive output pyroelectric current. This positive current is defined as the pyroelectric + photocurrent. When the temperature remains constant, the pyroelectric current disappears, leaving only a stable photocurrent plateau. When the laser is turned off, the temperature of the photodetector decreases, causing an increase in bound charge and generating a reverse pyroelectric current. This photoinduced change in ferroelectric polarization modulates the photoelectric process of interface carriers, enabling self-powered photodetection while improving photoelectric performance.

[0019] 3. The photodetector based on one-dimensional and three-dimensional hybrid perovskite ferroelectric film / P3HT heterojunction exhibits high moisture resistance and stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Schematic diagram of the structure of the photoelectric detector of the present invention.

[0021] Figure 2 Flowchart for preparing the photodetector of the present invention.

[0022] Figure 3 (a) SEM image, (b) XRD image and (c) TEM image of the one-dimensional and three-dimensional hybrid perovskite ferroelectric thin film prepared in Example 1 of the present invention.

[0023] Figure 4 This is a cross-sectional SEM image of the photodetector based on the one-dimensional and three-dimensional hybrid perovskite ferroelectric film / P3HT heterojunction in Example 1 of the present invention.

[0024] Figure 5 This is a current-time (It) curve (fourth-order response) diagram of the self-powered photodetector based on one-dimensional and three-dimensional hybrid perovskite ferroelectric film / P3HT heterojunction in Example 1 of the present invention.

[0025] Figure 6 This is a stability diagram of the self-powered photodetector in Example 1 of the present invention under high humidity (relative humidity of 80±10%) conditions.

[0026] Figure 7 This is a graph showing the It characteristic of the flexible photodetector after the anti-bending test in Example 2 of the present invention. DETAILED DESCRIPTION

[0027] The present invention is described in detail below with reference to the accompanying drawings.

[0028] In the present invention, both the rigid photodetector and the flexible photodetector are characterized by using a Stanford SRS current preamplifier (SR570) and a Stanford SRS function generator (DS345) system to characterize their working performance characteristics.

[0029] Reference Figure 1 The present invention is a self-powered photodetector based on a one-dimensional and three-dimensional mixed perovskite ferroelectric film / P3HT heterojunction, which comprises, from bottom to top, a conductive substrate layer (1), a one-dimensional and three-dimensional mixed perovskite ferroelectric film layer (2), a P3HT layer (3) and a metal top electrode layer (4).

[0030] The heterojunction is composed of a one-dimensional and three-dimensional mixed perovskite ferroelectric thin film layer (2) and a P3HT layer (3).

[0031] The described conductive base layer (1) refers to a conductive layer provided on a substrate. The conductive layer is any one of indium tin oxide (ITO), fluorine-doped tin dioxide (FTO), silicon, etc., with a size of 1×1 cm 2 -5×5 cm 2 .

[0032] The thickness of the described one-dimensional and three-dimensional hybrid perovskite ferroelectric thin film layer (2) is 450 - 550 nm.

[0033] The one-dimensional and three-dimensional hybrid perovskite ferroelectric thin film is composed of a mixture of one-dimensional metal halide perovskite and three-dimensional metal halide perovskite. Among them, the one-dimensional metal halide perovskite is the ferroelectric material TMIMPbI3, and the three-dimensional metal halide perovskite is MAPbI3, FA x MA y Cs 1-x-y PbI3 (0 < x < 1, 0 < y < 1, x + y < 1) or MA x Cs 1-x PbI3 (0 < x < 1), etc.

[0034] The described metal top electrode layer (4) is located on the P3HT layer (3), and it uses one of gold, platinum, and nickel electrodes, with a thickness of 60 - 300 nm.

[0035] Referring to Figure 2 , the method for preparing a self-powered photodetector based on a one-dimensional and three-dimensional hybrid perovskite ferroelectric thin film / P3HT heterojunction in the present invention is given as the following five examples.

[0036] Example 1

[0037] Prepare an ITO glass conductive substrate, a one-dimensional TMIMPbI3 and three-dimensional MAPbI3 hybrid perovskite ferroelectric thin film / P3HT heterojunction, and a self-powered pyroelectric photodetector with a gold metal top electrode.

[0038] 1) First, ultrasonically clean an ITO conductive substrate with a size of 1×1 cm 2 successively in acetone, ethanol, and deionized water for 15 min, then blow it dry with a dry nitrogen stream, and then treat it with 80 W of oxygen plasma for 10 min. Further, fully immerse the substrate in a 0.4 wt% aqueous solution of PEIE (polyethyleneimine) for 30 s, then wash it in deionized water for 3 s, and finally perform thermal annealing at 100 °C for 10 min to improve the wettability of the substrate to MAAc.

[0039] 2) Preparation of a perovskite precursor solution: 0.56 M (0.56 M refers to the concentration of PbI2 and Pb(SCN)2) of a lead salt with a molar ratio of 9:1 (PbI2:Pb(SCN)2), 0.56 M MAI, and 3.6 mM TMIMI were added to MAAc and stirred at 60°C for 12 hours. A 0.025 wt% 1,3-DAP solution was then added to the solution to obtain a perovskite precursor solution.

[0040] 3) Preparation of one-dimensional and three-dimensional mixed perovskite ferroelectric thin film: Fix the substrate on a heated spin coater, heat to 90°C and keep it constant, take 25μL of perovskite precursor solution and drop it on the conductive substrate, and spin coat it at 4000rpm for 20s. Anneal at 60°C and 100°C for 2min and 2min respectively, and finally obtain a one-dimensional and three-dimensional mixed perovskite ferroelectric thin film through chemical reaction. In order to reduce the defects of the material and improve the stability of the film, the surface of the film is further cleaned with a mixed solution of cyclohexane and tert-amyl alcohol with a volume ratio of 4:1, and then repaired with a mixed solution of MAI and TEA with a concentration of 0.2mg / mL to obtain a low-defect, high-stability one-dimensional and three-dimensional mixed perovskite ferroelectric film (the one-dimensional metal halide perovskite is TMIMPbI3, and the three-dimensional metal halide perovskite is MAPbI3). The corresponding SEM images, XRD images, and TEM images are shown in Figure 2. Figure 3 (a), (b), and (c) in the middle. The SEM image shows that the surface morphology of the one-dimensional and three-dimensional hybrid perovskite ferroelectric film is uniform and pinhole-free. The XRD image shows that the two main diffraction peaks at 14.2° and 28.5° correspond to the (110) and (220) crystal planes of MAPbI3, respectively, indicating that the perovskite film has a good crystal orientation and a tetragonal structure. Since the amount of one-dimensional perovskite added is too small, the one-dimensional phase cannot be seen in the XRD image. Further TEM images show the coexistence of one-dimensional and three-dimensional phases.

[0041] 4) P3HT was spin-coated in a chlorobenzene solution (10 mg / mL) onto a low-defect, high-stability one-dimensional and three-dimensional hybrid perovskite ferroelectric film to obtain a one-dimensional and three-dimensional hybrid perovskite ferroelectric film / P3HT heterojunction.

[0042] 5) Using thermal evaporator The gold electrode layer was deposited at a speed of 80 nm thick to obtain a self-powered photodetector based on a one-dimensional and three-dimensional hybrid perovskite ferroelectric film / P3HT heterojunction. The corresponding cross-sectional SEM image is shown below. Figure 4 Finally, the wires and the conductive electrodes were connected with silver paste and then connected to the test platform for testing. Under the irradiation of 532nm laser, the It curve (fourth-order response) at zero bias voltage is shown in the figure below. Figure 5As shown. Under zero bias, the fourth-order photoresponse dynamics caused by the optical switch can be seen from the figure. When the photodetector is in the dark state, there is only dark current, which is the first-order response; when the 532nm laser is turned on, the device generates photoinduced carriers, which are separated by the built-in electric field induced by the pn junction and ferroelectricity, generating photocurrent; at the same time, due to the increase in thermal vibration, the temperature rise caused by light will disrupt the random oscillation state of the electric dipoles in the one-dimensional and three-dimensional perovskite mixed ferroelectric film, resulting in a decrease in ferroelectric polarization charge and the generation of pyroelectric current. Therefore, the second-order response generates pyroelectric current and photocurrent. When the laser is continuously irradiated and the temperature remains unchanged, the pyroelectric current disappears, leaving only a stable photocurrent, which is the third-order response. When the laser is turned off, the temperature drop of the photodetector will cause the bound charge to increase, generating a reverse pyroelectric current, which is the fourth-order response. The stability performance of the photodetector device stored under high humidity (relative humidity of 80±10%) for 39 days is shown as follows. Figure 6 As can be seen from the figure, the device's photoresponse retains 100% of its initial photocurrent, while the pyroelectric response retains 82% of its initial value, indicating that the photodetection device has ultra-high humidity stability.

[0043] Example 2

[0044] A self-powered pyroelectric photodetector with an ITO / PEN flexible conductive substrate, a one-dimensional TMIMPbI3 and three-dimensional MAPbI3 mixed perovskite ferroelectric film / P3HT heterojunction, and a gold metal top electrode was prepared.

[0045] 1) First, make a 1×1cm 2 An ITO / PEN (polyethylene naphthalate) flexible conductive substrate was ultrasonically cleaned in acetone, ethanol, and deionized water for 15 minutes, followed by drying with a stream of dry nitrogen and then treated with 80W oxygen plasma for 10 minutes. The substrate was then immersed in a 0.4wt% aqueous solution of PEIE for 30 seconds, then rinsed in deionized water for 3 seconds, and finally thermally annealed at 100°C for 10 minutes to improve its wettability with MAAc.

[0046] 2) Preparation of a perovskite precursor solution: 0.56 M lead salt (PbI₂:Pb(SCN)₂) (a molar ratio of 9:1), 0.56 M MAI, and 3.6 mM TMIMI were added to MAAc and stirred at 60°C for 12 h. A 0.025 wt% 1,3-DAP solution was then added to the solution to obtain a perovskite precursor solution.

[0047] 3) Preparation of 1D / 3D Hybrid Perovskite Ferroelectric Thin Films: A substrate was mounted on a heated spin coater and heated to 90°C. 25 μL of the perovskite precursor solution was dropwise added to the conductive substrate and spin-coated at 4000 rpm for 20 seconds. Annealing was performed at 60°C for 2 minutes and 100°C for 2 minutes, respectively, to obtain a 1D / 3D hybrid perovskite ferroelectric thin film. To reduce defects and improve film stability, the film was further cleaned with a 4:1 volume ratio of cyclohexane and tert-amyl alcohol. The film was then repaired with a 0.2 mg / mL solution of MAI and 0.2 mg / mL of TEA, resulting in a low-defect, highly stable 1D / 3D hybrid perovskite ferroelectric thin film (TMIMPbI3 for the 1D metal halide perovskite and MAPbI3 for the 3D metal halide perovskite).

[0048] 4) P3HT was spin-coated in a chlorobenzene solution (10 mg / mL) onto a low-defect, high-stability one-dimensional and three-dimensional hybrid perovskite ferroelectric film to obtain a one-dimensional and three-dimensional hybrid perovskite ferroelectric film / P3HT heterojunction.

[0049] 5) Using thermal evaporator The gold electrode layer was deposited at a speed of 80 nm to a thickness, resulting in a self-powered flexible photodetector based on a one-dimensional and three-dimensional hybrid perovskite ferroelectric film / P3HT heterojunction. Finally, the wires were connected to the conductive electrodes with silver paste and then connected to the test platform for testing. The It characteristic curves before and after bending are shown in the figure below. Figure 7 As shown in the figure, it can be seen that after 1000 bending cycles, the attenuation of the photocurrent and pyroelectric current is less than 2%, indicating that the self-powered flexible photodetector based on one-dimensional and three-dimensional hybrid perovskite ferroelectric film / P3HT heterojunction has good mechanical stability.

[0050] Example 3

[0051] Preparation of ITO conductive substrate, one-dimensional TMIMPbI3 and three-dimensional MA 0.5 Cs 0.5 Self-powered pyroelectric photodetector with PbI3 mixed perovskite ferroelectric film / P3HT heterojunction and gold metal top electrode.

[0052] 1) First, make a 1×1cm 2 The ITO conductive substrate was ultrasonically cleaned in acetone, ethanol, and deionized water for 15 minutes, followed by drying with a stream of dry nitrogen and then treated with 80W oxygen plasma for 10 minutes. The substrate was then immersed in a 0.4wt% aqueous solution of PEIE for 30 seconds, then rinsed in deionized water for 3 seconds, and finally thermally annealed at 100°C for 10 minutes to improve its wettability with MAAc.

[0053] 2) Preparation of a perovskite precursor solution: 0.56 M lead salt (PbI2:Pb(SCN)2) (a molar ratio of 9:1), 0.28 M MAI, 0.28 M CsI, and 3.6 mM TMIMI were added to MAAc and stirred at 60°C for 12 h. A 0.025 wt% 1,3-DAP solution was then added to the solution to obtain a perovskite precursor solution.

[0054] 3) Preparation of one-dimensional and three-dimensional mixed perovskite ferroelectric thin films: Fix the substrate on a heated spin coater, heat it to 90°C and keep it constant, take 25μL of perovskite precursor solution and drop it on the conductive substrate, and spin coat it at 4000rpm for 20s. Anneal at 60°C and 100°C for 2min and 2min respectively to obtain a one-dimensional and three-dimensional mixed perovskite ferroelectric thin film. In order to reduce the defects of the material and improve the stability of the film, the surface of the film is further cleaned with a mixed solution of cyclohexane and tert-amyl alcohol with a volume ratio of 4:1, and then repaired with a mixed solution of MAI and TEA with a concentration of 0.2mg / mL to obtain a low-defect, high-stability one-dimensional and three-dimensional mixed perovskite ferroelectric film (the one-dimensional metal halide perovskite is TMIMPbI3, and the three-dimensional metal halide perovskite is MA 0.5 Cs 0.5 PbI3).

[0055] 4) P3HT was spin-coated in a chlorobenzene solution (10 mg / mL) onto a low-defect, high-stability one-dimensional and three-dimensional hybrid perovskite ferroelectric film to obtain a one-dimensional and three-dimensional hybrid perovskite ferroelectric film / P3HT heterojunction.

[0056] 5) Using thermal evaporator A gold electrode layer was deposited at a speed of 100 nm to a thickness of 80 nm, resulting in a self-powered photodetector based on a one-dimensional and three-dimensional hybrid perovskite ferroelectric thin film / P3HT heterojunction. Finally, the wires were connected to the conductive electrodes with silver paste and then connected to a test platform for testing.

[0057] Example 4

[0058] Preparation of ITO conductive substrate, one-dimensional TMIMPbI3 and three-dimensional FA 0.3 MA 0.5 Cs 0.2 Self-powered pyroelectric photodetector with PbI3 mixed perovskite ferroelectric film / P3HT heterojunction and gold metal top electrode.

[0059] 1) First, make a 1×1cm 2The ITO conductive substrate was ultrasonically cleaned in acetone, ethanol, and deionized water for 15 minutes, followed by drying with a stream of dry nitrogen and then treated with 80W oxygen plasma for 10 minutes. The substrate was then immersed in a 0.4wt% aqueous solution of PEIE for 30 seconds, then rinsed in deionized water for 3 seconds, and finally thermally annealed at 100°C for 10 minutes to improve its wettability with MAAc.

[0060] 2) Preparation of a perovskite precursor solution: 0.56M lead salt (PbI2:Pb(SCN)2) (a molar ratio of 9:1), 0.168M FAI, 0.28M MAI, 0.112M CsI, and 3.6mM TMIMI were added to MAAc and stirred at 60°C for 12 hours. A 0.025wt% 1,3-DAP solution was then added to the solution to obtain a perovskite precursor solution.

[0061] 3) Preparation of one-dimensional and three-dimensional mixed perovskite ferroelectric thin films: Fix the substrate on a heated spin coater, heat it to 90°C and keep it constant, take 25μL of perovskite precursor solution and drop it on the conductive substrate, and spin coat it at 4000rpm for 20s. Anneal at 60°C and 100°C for 2min and 2min respectively to obtain a one-dimensional and three-dimensional mixed perovskite ferroelectric thin film. In order to reduce the defects of the material and improve the stability of the film, the surface of the film is further cleaned with a mixed solution of cyclohexane and tert-amyl alcohol with a volume ratio of 4:1, and then repaired with a mixed solution of MAI and TEA with a concentration of 0.2mg / mL to obtain a low-defect, high-stability one-dimensional and three-dimensional mixed perovskite ferroelectric thin film (the one-dimensional metal halide perovskite is TMIMPbI3, and the three-dimensional metal halide perovskite is FA 0.3 MA 0.5 Cs 0.2 PbI3).

[0062] 4) P3HT was spin-coated in a chlorobenzene solution (10 mg / mL) onto a low-defect, high-stability one-dimensional and three-dimensional hybrid perovskite ferroelectric film to obtain a one-dimensional and three-dimensional hybrid perovskite ferroelectric film / P3HT heterojunction.

[0063] 5) Using thermal evaporator A gold electrode layer was deposited at a speed of 100 nm to a thickness of 80 nm, resulting in a self-powered photodetector based on a one-dimensional and three-dimensional hybrid perovskite ferroelectric thin film / P3HT heterojunction. Finally, the wires were connected to the conductive electrodes with silver paste and then connected to a test platform for testing.

[0064] Example 5

[0065] A self-powered pyroelectric photodetector with an ITO conductive substrate, a one-dimensional TMIMPbI3 and three-dimensional MAPbI3 mixed perovskite ferroelectric film / P3HT heterojunction, and a gold metal top electrode was prepared.

[0066] 1) First, make a 1×2cm 2 The ITO conductive substrate was ultrasonically cleaned in acetone, ethanol, and deionized water for 20 minutes, dried with a stream of dry nitrogen, and then treated with 80W oxygen plasma for 20 minutes. The substrate was then immersed in a 0.4wt% aqueous solution of PEIE for 60 seconds, rinsed in deionized water for 10 seconds, and finally thermally annealed at 110°C for 10 minutes to improve its wettability with MAAc.

[0067] 2) Prepare a perovskite precursor solution: Add 0.5 M lead salt (PbI₂:Pb(SCN)₂) (a 9:1 molar ratio), 0.5 M MAI, and 3.6 mM TMIMI to MAAc and stir at 50°C for 12 hours. Further, add 0.025 wt% 1,3-DAP solution to the solution to obtain a perovskite precursor solution.

[0068] 3) Preparation of 1D / 3D Hybrid Perovskite Ferroelectric Thin Films: A substrate was mounted on a heated spin coater and heated to 90°C. 30 μL of the perovskite precursor solution was dropwise added to the conductive substrate and spin-coated at 4000 rpm for 20 seconds. Annealing was performed at 65°C for 5 minutes and 110°C for 5 minutes, respectively, to obtain a 1D / 3D hybrid perovskite ferroelectric thin film. To reduce defects and improve film stability, the film was further cleaned with a 4:1 volume ratio of cyclohexane and tert-amyl alcohol. The film was then repaired with a 0.2 mg / mL solution of MAI and 0.2 mg / mL of TEA, resulting in a low-defect, highly stable 1D / 3D hybrid perovskite ferroelectric thin film (TMIMPbI3 for the 1D metal halide perovskite and MAPbI3 for the 3D metal halide perovskite).

[0069] 4) P3HT was spin-coated in a chlorobenzene solution (20 mg / mL) onto a low-defect, high-stability one-dimensional and three-dimensional hybrid perovskite ferroelectric film to obtain a one-dimensional and three-dimensional hybrid perovskite ferroelectric film / P3HT heterojunction.

[0070] 5) Using thermal evaporator A platinum electrode layer was deposited at a rate of 100 nm to a thickness of 80 nm, resulting in a self-powered photodetector based on a one-dimensional and three-dimensional hybrid perovskite ferroelectric thin film / P3HT heterojunction. Finally, the wires were connected to the conductive electrodes using silver paste and then connected to a test platform for testing.

Claims

1. A self-powered photodetector based on a one-dimensional and three-dimensional hybrid perovskite ferroelectric film / P3HT heterojunction, characterized by: From bottom to top, it includes a conductive substrate layer, a one-dimensional and three-dimensional hybrid perovskite ferroelectric thin film layer, a P3HT layer, and a metal top electrode layer; the heterojunction is composed of a one-dimensional and three-dimensional hybrid perovskite ferroelectric thin film layer and a P3HT layer; the one-dimensional and three-dimensional hybrid perovskite ferroelectric thin film layer is a mixture of a one-dimensional metal halide perovskite material and a three-dimensional metal halide perovskite material; The one-dimensional metal halide perovskite material is TMIMPbI3, and the three-dimensional metal halide perovskite material is MAPbI3, FA x MA y Cs 1-x-y PbI3 or MA x Cs 1-x PbI3; in MA x Cs 1-x PbI3 formula, 0 < x < 1; in FA x MA y Cs 1-x-y PbI3 formula, 0 < x < 1, 0 < y < 1, x + y < 1; The one-dimensional and three-dimensional mixed perovskite ferroelectric thin film layer is prepared by heating and spin-coating a perovskite precursor solution, and is cleaned and repaired after the heating and spin-coating.

2. A method for preparing a self-powered photodetector based on a one-dimensional and three-dimensional hybrid perovskite ferroelectric film / P3HT heterojunction, characterized in that: The steps include: a. Pre-treating the conductive substrate; b. Prepare a perovskite precursor solution: Add 0.5-0.6 M lead salt (PbI2:Pb(SCN)2) in a molar ratio of 9:1, 0.5-0.6 M iodide cation salt, and 3-3.6 mM TMIMI to MAAc, and stir at 50-60 °C for 10-12 h. Further, add 0.02-0.025 wt% 1,3-diaminopropane solution to the above solution to obtain a perovskite precursor solution. c. Preparation of 1D / 3D hybrid perovskite ferroelectric thin films: Fix the conductive substrate on a heated spin coater and heat it to 90-100°C and keep it constant. Add 20-30 μL of the perovskite precursor solution dropwise onto the conductive substrate and spin coat at 4000 rpm for 20-30 s. Annealing at 60-65°C and 100-110°C for 1-5 minutes and 1-5 minutes, respectively, yields a one-dimensional and three-dimensional hybrid perovskite ferroelectric thin film. The surface is then cleaned with a 4:1 volume ratio of cyclohexane and tert-amyl alcohol, and then repaired with a 0.2-0.3 mg / mL solution of MAI and 0.2-0.3 mg / mL of tetraethylammonium iodide to yield a low-defect, high-stability one-dimensional and three-dimensional hybrid perovskite ferroelectric thin film. d. Spin-coating P3HT in a chlorobenzene solution onto a low-defect, high-stability one-dimensional and three-dimensional hybrid perovskite ferroelectric film to obtain a one-dimensional and three-dimensional hybrid perovskite ferroelectric film / P3HT heterojunction; e. Depositing a metal top electrode using a thermal evaporator; In step b, the iodide cationic salt is MAI, a mixture of MAI and CsI, or a mixture of MAI, CsI and FAI.

3. The method for preparing a self-powered photodetector based on a one-dimensional and three-dimensional hybrid perovskite ferroelectric thin film / P3HT heterojunction according to claim 2, wherein: In step a, the conductive substrate is pretreated, specifically, the conductive substrate is fully immersed in a 0.4 wt % polyethyleneimine aqueous solution, then washed in deionized water, and finally thermally annealed.

4. The method for preparing a self-powered photodetector based on a one-dimensional and three-dimensional hybrid perovskite ferroelectric thin film / P3HT heterojunction according to claim 2, wherein: In step a, the conductive substrate refers to a substrate having a conductive layer provided thereon, and the conductive layer is indium tin oxide, fluorine-doped tin dioxide or silicon.

5. The method for preparing a self-powered photodetector based on a one-dimensional and three-dimensional hybrid perovskite ferroelectric thin film / P3HT heterojunction according to claim 2, wherein: In step e, the metal top electrode is deposited at a rate of 0.1-1.0 Å / s, and the thickness of the metal top electrode is 60-300 nm.

6. The preparation method of the self-powered photodetector based on the one-dimensional and three-dimensional hybrid perovskite ferroelectric thin film / P3HT heterojunction according to claim 2, wherein the low-defect and high-stability one-dimensional and three-dimensional hybrid perovskite ferroelectric thin film obtained in step c is composed of a one-dimensional metal halide perovskite material and a three-dimensional metal halide perovskite material; the one-dimensional metal halide perovskite material is TMIMPbI3, and the three-dimensional metal halide perovskite materials are MAPbI3, FA x MA y Cs 1-x-y PbI3 or MA x Cs 1-x PbI3; in MA x Cs 1-x PbI3 formula, 0 < x < 1; in FA x MA y Cs 1-x-y PbI3 formula, 0 < x < 1, 0 < y < 1, x + y < 1.

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