Perovskite solar cell doped with pyridinium compound and preparation method thereof

Abstract

The invention relates to the technical field of solar cells, in particular to a pyridinium compound doped perovskite solar cell and a preparation method thereof, a perovskite layer of the cell comprises Pb < 2 + > and a pyridinium compound doped in the perovskite layer, and the molar ratio of the pyridinium compound to the Pb < 2 + > is 1: 500-3: 250. By doping the pyridinium compound and Pb < 2 + >, the perovskite solar cell constructs a four-dimensional synergistic interaction mechanism of defect passivation, ultraviolet protection, energy conversion optimization and environmental protection. The M molecule not only solves the key problem that the perovskite material is easy to be damaged by ultraviolet and influenced by surface defects, but also provides a new solution for improving the comprehensive performance of the solar cell by improving the light utilization rate and the environmental tolerance. The preparation method of the M-doped perovskite solar cell provided by the invention is simple in process, easy to operate and beneficial to large-scale production.

Description

Technical Field

[0001] The present invention relates to the technical field of solar cells, and particularly to a perovskite solar cell doped with pyridinium compounds and a preparation method thereof. Background Art

[0002] As an emerging photovoltaic technology, perovskite solar cells exhibit great application potential in the photovoltaic field due to their excellent photoelectric conversion efficiency and low-cost solution processing characteristics. However, during their actual application process, they still face many stability problems, mainly reflected in environmental stability and thermal stability. In terms of environmental stability, perovskite materials are extremely sensitive to water vapor and are prone to irreversible crystal structure degradation in a humid environment, resulting in device performance decline. Although the moisture resistance can be improved to a certain extent by optimizing the material composition and adopting advanced encapsulation technologies, there is still room for further improvement. Perovskite materials are prone to phase separation and ion migration when the temperature changes, resulting in insufficient thermal stability. Adopting a mixed component design and an interface engineering strategy helps to inhibit thermally induced structural damage, thereby enhancing the stability of the device in a high-temperature environment.

[0003] The sensitivity of perovskite materials to ultraviolet light is also one of the key factors restricting their long-term stability. Ultraviolet light irradiation often triggers interfacial photocatalytic reactions, accelerating material decomposition and leading to a decline in device performance. Developing an ultraviolet-stable interface layer or replacing photosensitive transport materials has become an effective way to alleviate this problem. At the same time, the quantum yield of perovskite materials for ultraviolet light is relatively low, and the utilization efficiency is not high, further restricting the photoelectric conversion efficiency of the battery. Therefore, enhancing the absorption and utilization ability of perovskite materials for ultraviolet light is an important direction for improving the overall performance of the battery.

[0004] Interface defects are the main inducement for carrier non-radiative recombination, which not only significantly reduces the battery efficiency but also accelerates the aging process of the device. Through defect passivation technology and energy level matching optimization, the interfacial defect density can be effectively reduced, and the long-term stability of the device can be enhanced. Current research is committed to gradually solving the above problems through multi-dimensional strategies to synergistically regulate materials, interfaces, and device structures, and promoting the transformation of perovskite solar cells from laboratory research to industrial application.

[0005] In summary, although perovskite solar cells exhibit significant advantages in terms of photoelectric conversion efficiency and cost control, they still have the following problems to be solved: First, the battery performance is limited by the defects at the perovskite grain boundaries; second, the battery stability is poor due to ultraviolet light; third, the utilization rate of ultraviolet light by perovskite solar cells is relatively low, resulting in the inability of ultraviolet light to be effectively converted into electrical energy, causing a spectral response valley and limiting the upper limit of the photoelectric conversion efficiency. Summary of the Invention

[0006] The present invention aims to solve at least one of the technical problems existing in the related art. To this end, the first object of the present invention is to provide a perovskite solar cell doped with a pyridinium compound; the second object of the present invention is to provide a method for preparing a perovskite solar cell doped with a pyridinium compound.

[0007] To achieve the first object, the technical solution adopted by the present invention is as follows: A perovskite solar cell doped with a pyridinium compound, comprising a perovskite layer, wherein the perovskite layer comprises Pb doped therein 2+ and a pyridinium compound; wherein, the molar ratio of the pyridinium compound to Pb 2+ is 1:500 to 3:250; The molecular structural formula of the pyridinium compound is as follows: .

[0008] The pyridinium compound (hereinafter referred to as M), as one of the doping compounds in the perovskite layer of the perovskite solar cell, mainly plays the following roles: First, the M molecule realizes the multi-functional synergistic regulation of the perovskite layer through the bipolar terminal structure. The halogen element contained in its molecular structural formula can form a stable coordination bond with the undercoordinated Pb² + on the perovskite surface, effectively compensating for the halogen vacancy defect, significantly reducing the probability of surface recombination of photo-generated carriers, and thus improving the device efficiency.

[0009] Second, the M molecule has strong absorption characteristics in the ultraviolet band, can build a light protection barrier, and effectively inhibits the degradation of perovskite components caused by ultraviolet irradiation. This ultraviolet protection mechanism not only protects the perovskite material from ultraviolet damage, but also passivates defects through intermolecular configuration transformation, further optimizing the stability of the perovskite layer.

[0010] Third, the high fluorescence quantum yield of the M molecule enables it to exhibit excellent emission characteristics in the visible light region, and can efficiently convert the absorbed ultraviolet light into visible light output. This not only enhances the response of the perovskite layer in the short-wave region, but also further improves the photoelectric conversion efficiency of the battery through energy conversion optimization. This dual light management mechanism realizes the synergistic effect of ultraviolet protection and light energy utilization.

[0011] Fourth, based on the hydrophobic characteristics of organic cations, the M molecule forms a dynamic protection layer on the surface of the perovskite layer, effectively blocking the penetration of water molecules and inhibiting the ion migration process driven by thermal defects. This characteristic significantly enhances the tolerance of the perovskite layer in the actual working environment and delays the performance degradation caused by environmental factors. By inhibiting the ion migration effect and simultaneously reducing the surface defect density, the long-term stability of the solar cell can be doubly guaranteed.

[0012] Therefore, the present invention dopes M and Pb 2+ A four-dimensional synergistic mechanism of defect passivation, ultraviolet protection, energy conversion optimization and environmental protection is constructed. The M molecule not only solves the key problems that perovskite materials are vulnerable to ultraviolet damage and surface defects, but also provides a new solution for improving the comprehensive performance of solar cells by enhancing light utilization efficiency and environmental tolerance.

[0013] Furthermore, it also includes a substrate, an electron transport layer, a hole transport layer and a metal electrode layer, and the substrate, the electron transport layer, the perovskite layer, the hole transport layer and the metal electrode layer are sequentially arranged vertically from bottom to top.

[0014] Furthermore, the substrate is selected from glass materials doped with fluorine-doped tin oxide.

[0015] Furthermore, the electron transport layer is selected from titanium dioxide materials.

[0016] Furthermore, an interface modification layer is disposed on the electron transport layer. The interface modification layer is selected from lithium fluoride materials, and the thickness of the interface modification layer is 0.3 - 0.8 nm.

[0017] Furthermore, the hole transport layer is selected from 2,2',7,7'-tetrakis[N,N-bis(4-methoxyphenyl)amino]-9,9'-spirobifluorene (Spiro-OMeTAD) materials or poly(3-hexylthiophene-2,5-diyl) (P3HT) materials.

[0018] Furthermore, the metal in the metal electrode layer is selected from any one of Au, Ag and Cu.

[0019] To achieve the second object, the technical solution adopted by the present invention is: A preparation method of a perovskite solar cell doped with M, which is used to prepare the perovskite solar cell doped with M described in any one of the above, includes the following steps: S100. Prepare an electron transport layer on the substrate; S200. After adding formamidinium iodide (FAI), methylammonium bromide (MABr), cesium iodide (CsI) and lead iodide (PbI2) into an organic solvent to dissolve and obtain a perovskite precursor solution I, add M and stir evenly to obtain a perovskite precursor solution II. Spin-coat the perovskite precursor solution II on the electron transport layer by gradient spin-coating to obtain a perovskite layer; S300. Prepare a hole transport layer on the perovskite layer; S400. Deposit a metal on the hole transport layer to obtain a metal electrode layer.

[0020] Further, in step S200, the organic solvent is selected from dimethylformamide (DMF) and / or dimethyl sulfoxide (DMSO).

[0021] One or more of the above technical solutions in the embodiments of the present invention have at least one of the following technical effects: The perovskite solar cell doped with M provided by the present invention adds an M molecule containing a halogen element and a polar terminal substitution as an organic cation passivator to the perovskite layer, compensates for defect sites, inhibits ion migration, and promotes the transport of photo-generated carriers at the perovskite grain boundaries by virtue of the conjugated ionic configuration of the passivator itself.

[0022] The M molecule has the characteristics of absorbing ultraviolet light and emitting visible light fluorescence, provides ultraviolet protection for the battery, and enhances the utilization rate of the perovskite solar cell in the ultraviolet light region.

[0023] By using the M molecule to modify the grain boundaries of the perovskite layer, water molecules can be effectively prevented from entering the perovskite grain boundaries, the damage of thermal stress to the perovskite layer can be inhibited, so that the performance loss in the actual working environment is significantly reduced, and the stability of the perovskite solar cell during operation is further improved.

[0024] The preparation method of the perovskite solar cell doped with M provided by the present invention has a simple process and is easy to operate, which is conducive to large-scale production.

[0025] The additional aspects and advantages of the present invention will be partly given in the following description, partly will become obvious from the following description, or will be understood through the practice of the present invention. Description of the Drawings

[0026] Figure 1 It is a schematic structural diagram of a perovskite solar cell doped with a pyridinium compound provided by an embodiment of the present invention.

[0027] Figure 2 It is a ¹H NMR spectrum of the pyridinium compound provided in Example 1 of the present invention.

[0028] Reference Signs: 100, substrate; 200, electron transport layer; 201, interface modification layer; 300, perovskite layer; 400, hole transport layer; 500, metal electrode layer. Detailed Embodiments

[0029] To make the objectives, technical solutions, and advantages of the present invention clearer, the technical solutions in the present invention will be clearly and completely described below in conjunction with specific embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of them. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention. The following embodiments are used to illustrate the present invention, but cannot be used to limit the scope of the present invention.

[0030] As Figure 1 shown, the perovskite solar cell doped with M includes a substrate 100, an electron transport layer 200, a perovskite layer 300, a hole transport layer 400, and a metal electrode layer 500, which are sequentially arranged longitudinally from bottom to top; The perovskite layer includes Pb 2+ and M, and Pb 2+ and M are doped into the perovskite layer; The molar ratio of M to Pb 2+ is 1:500 to 3:250; The molecular structural formula of M is as follows: .

[0031] According to a specific embodiment provided by the present invention, an interface modification layer 201 is provided on the electron transport layer 200. The interface modification layer 201 is selected from lithium fluoride materials and has a thickness of 0.3 to 0.8 nm.

[0032] A method for preparing a perovskite solar cell doped with M includes the following steps: S100. Prepare an electron transport layer on the substrate; S200. After adding FAI, MABr, CsI, and PbI2 to an organic solvent and dissolving them to obtain a perovskite precursor solution I, then add M and stir to dissolve to obtain a perovskite precursor solution II. Spin-coat the perovskite precursor solution II on the electron transport layer by gradient spin-coating to obtain a perovskite layer; Among them, the solubility of lead iodide in the perovskite precursor solution I is 1 to 1.7 mol / L; S300. Prepare a hole transport layer on the perovskite layer; S400. Deposit metal on the hole transport layer to obtain a metal electrode layer.

[0033] In the following embodiments, the experimental methods used are all conventional methods unless otherwise specified, and the materials, reagents, etc. used are carried out according to the techniques or conditions described in the literature in this field or according to the product specifications. Unless otherwise specified, they can all be obtained from commercial sources.

[0034] Example 1 Preparation of M is as described below: Under an argon atmosphere, 4-pyridinecarboxaldehyde (200 mg, 1.9 mmol) and ethanedithioamide (50 mg, 0.4 mmol) were successively added to DMF (8 ml). After stirring to dissolve, the mixture was heated to 140 °C and refluxed for 5 h, then cooled to room temperature, filtered, and the filter cake was washed 4 times with deionized water. After drying, intermediate Ⅰ was obtained.

[0035] Under an argon atmosphere, intermediate Ⅰ (200 mg, 0.7 mmol) was added to p-bromobenzyl bromide (7 ml). After stirring to dissolve, the mixture was heated to 120 °C and refluxed for 10 h. After washing with n-hexane, the mixture was filtered to obtain the crude product of M . The crude product of M was purified using an acidic silica gel column, and the eluent was a mixed solvent of ethyl acetate and petroleum ether (the volume ratio of ethyl acetate to petroleum ether was 5:1). After separation by silica gel column chromatography, the target product was collected and concentrated to obtain purified M , and its nuclear magnetic resonance hydrogen spectrum (¹H NMR) is shown as Figure 2 follows.

[0036] Using M , a perovskite solar cell doped with M was prepared.

[0037] I. Treatment of the substrate is as follows: Fluorine-doped Tin Oxide (FTO) glass was laser-etched to form a desired patterned surface. Subsequently, a lint-free cloth was dipped in deionized water to remove surface particulate matter and soluble residues. Then, the treated substrate was successively immersed in glass cleaner, deionized water, isopropanol, and absolute ethanol for ultrasonic cleaning, and each solvent was cleaned for 20 min. After cleaning, it was dried with nitrogen and sent to an ozone ultraviolet cleaning machine for 30 min to thoroughly remove surface organic pollutants, obtaining a clean FTO substrate.

[0038] II. Preparation of the electron transport layer is as follows: The cleaned FTO substrate was immersed in a mixed solution of titanium tetrachloride and deionized water with a volume ratio of 1:50. The above system was placed in an incubator at 65 °C and allowed to stand for 4 h to form a dense TiO2 layer through a hydrolysis reaction. Then, the substrate was transferred to a heating platform at 190 °C for annealing for 30 min, and then sent to an ozone ultraviolet cleaning machine for 5 min to complete the preparation of the TiO2 electron transport layer.

[0039] Using a vacuum evaporation coating equipment, LiF is heated and evaporated, and uniformly deposited on the surface of the TiO2 electron transport layer with a coating thickness of 0.3 nm to form a LiF interfacial modification layer on the surface of the TiO2 electron transport layer.

[0040] III. Preparation of the perovskite layer, the process is as follows: FAI (137.4 g, 0.8 mol), MABr (1.7 g, 0.15 mol), CsI (1.3 g, 0.05 mol) and PbI2 (40.2 g, 1 mol) are added to a mixed solvent (580 ml) composed of DMF and DMSO. The volume ratio of DMF to DMSO in this mixed solvent is 4:1. Stir well to completely dissolve each component to obtain a perovskite precursor solution I. According to the preparation method of the above perovskite precursor solution I, 7 portions of perovskite precursor solution I are prepared, and are respectively denoted as: Group 0, Group 1, Group 2, Group 3, Group 4, Group 5 and Group 6; To the above perovskite precursor solutions I of Group 0, Group 1, Group 2, Group 3, Group 4, Group 5 and Group 6, 0, 2 mmol, 4 mmol, 6 mmol, 8 mmol, 10 mmol and 12 mmol of M are added to obtain perovskite precursor solutions II containing different molar ratios of M to Pb 2+ respectively.

[0041] Under a nitrogen atmosphere, the above different groups of perovskite precursor solutions II are respectively dropped onto the surface of the TiO2 electron transport layer coated with LiF, and the perovskite precursor solution II is spin-coated by a staged gradient spin-coating method. First, the substrate is rotated at a speed of 600 rpm for 15 seconds to extend the liquid film, and then the substrate is rotated at a high speed of 3500 rpm for 25 seconds to control the film formation thickness. 0.3 mL of toluene is injected as an anti-solvent 5 seconds before the end of the high-speed stage, and the oriented growth of crystal nuclei is controlled by adjusting the solvent polarity. After spin-coating is completed, the substrate is immediately transferred to a temperature-controlled platform at 100 °C for annealing for 15 min to obtain the perovskite layer.

[0042] The molar ratios of the pyridinium compounds to Pb 2+ in the perovskite layers of Group 0, Group 1, Group 2, Group 3, Group 4, Group 5 and Group 6 are different, being 0, 1:500, 2:250, 3:500, 1:125, 1:100, 3:250 respectively.

[0043] IV. A hole transport layer is respectively prepared on each of the above perovskite layers, and the process is as follows: P3HT (10 mg) is added to chlorobenzene (1 mL), stirred and dissolved to obtain a hole transport layer precursor solution. This solution is dropped onto the perovskite layer and spin-coated at a speed of 4000 rpm for 28 seconds to form a hole transport layer.

[0044] V. Preparation of the metal electrode layer is as follows: Using a vacuum evaporation equipment, deposit an Au electrode on the surface of the hole transport layer, control the deposition thickness to be 75 nm, and prepare 7 perovskite solar cell samples, which are respectively: Group 0 (as a control group): Perovskite solar cell without doping M; Groups 1 - 6 are perovskite solar cells doped with M. In groups 1 - 6, the molar ratio of M to Pb 2+ is 1:500, 1:250, 3:500, 1:125, 1:100, 3:250 respectively.

[0045] Test Example 1 Test of battery performance.

[0046] I. Detection of perovskite cell performance: To test the performance of perovskite solar cells, the performance differences of the 7 groups of solar cells with different doping ratios prepared above were systematically compared. All samples (with an effective area of 0.035 cm²) were tested for current - voltage characteristic curves under standard illumination conditions (AM.5G, 100 mW / cm²). The key performance indicators include: open - circuit voltage (Voc), short - circuit current density (Jsc), fill factor (fill factor, FF), and power conversion efficiency (Power Conversion Efficiency, PCE). The results are shown in Table 1.

[0047] It can be seen from the data provided in Table 1 that the power conversion efficiency of perovskite solar cells doped with M is generally better than that of the cells without doping this compound. When the molar ratio of doped M to Pb 2+ is 3:500 and 1:125, their power conversion efficiencies reach 22.5% and 22.4% respectively, which is significantly improved compared with the control samples without doping M. This result shows that M molecules can effectively optimize the carrier transport path and inhibit the effect of defect recombination.

[0048] II. To further explore whether M can enhance the response performance of perovskite solar cells to ultraviolet light by converting ultraviolet absorption into visible light output, the Enlitech QE - R quantum efficiency system was used to analyze the monochromatic incident photon - to - electron conversion efficiency (IPCE) of different groups of battery samples. The test focused on comparing the performance differences between perovskite solar cells doped with M and those without doping M in the ultraviolet band of 300 - 400 nm. The results are shown in Table 2.

[0049] From the data provided in Table 2, it can be known that the perovskite solar cell doped with M has enhanced response ability to ultraviolet light. This result indicates that M can convert ultraviolet light in the simulated sunlight spectrum into visible light. Since the perovskite layer has a stronger response to visible light, the utilization rate of ultraviolet light energy of the doped device finally increases.

[0050] Detection Example 2: Test of battery stability.

[0051] I. Test of battery water stability, the process is as follows: In order to evaluate the influence of M molecules on the moisture resistance performance of perovskite solar cells, the present invention carried out a long-term stability test on the perovskite solar cell doped with M and the control sample without doping M in an environment of 25 °C and relative humidity of 75%. Under dark conditions, the efficiency change of the solar cell was traced by regular (interval time of 400 h each time) efficiency detection, and the results are shown in Table 3.

[0052] From the data provided in Table 3, it can be known that after 2000 h of exposure to a high-humidity environment, the perovskite solar cell doped with M shows excellent stability, and its efficiency decay rate is controlled within 15%. In particular, the sample with a molar ratio of M to Pb 2+ of 3:250 still maintains 95.6% of the initial efficiency. In contrast, the control without doping M showed significant performance degradation at 800 h, and the efficiency loss exceeded 15%. This result indicates that the hydrophobic group and polar end in M molecules cooperate with each other, not only effectively blocking the penetration and erosion of environmental moisture, but also strengthening the perovskite grain boundary structure through coordination, thus significantly improving the water stability of the solar cell.

[0053] II. Test of battery thermal stability, the process is as follows: Perovskite solar cells are prone to irreversible degradation under the combined action of thermal stress and lattice defects, which seriously affects the long-term stability of the device. To verify the thermal stability enhancement effect of M, the 7 groups of samples prepared above were aged at a constant temperature of 85 °C, and the change of battery efficiency was continuously monitored. The results are shown in Table 4.

[0054] From the data provided in Table 4, it can be seen that the perovskite solar cells doped with M significantly inhibit the thermal degradation effect. The test results show that after aging, the efficiency retention rate of the cells doped with M remains at 87.4% - 93.7%, and among them, Group 4 reaches the highest retention rate of 93.7%. In contrast, the control group without M doping shows obvious performance degradation, and the efficiency retention rate drops sharply from the initial value of 100% to 61.5%. This result indicates that M achieves stabilization through a dual-pathway: its molecular functional groups selectively bind to the uncoordinated lead defects in the perovskite layer, thereby effectively eliminating the deep-level defect states; at the same time, its multi-polar molecular termini can act on multiple defect sites simultaneously, thus being able to inhibit the ion migration and defect proliferation processes induced by high temperature.

[0055] III. The ultraviolet light stability of the cells tested through a controlled accelerated aging experiment is as follows: The 7 groups of samples prepared above are irradiated continuously for 1500 h by an ultraviolet lamp with a wavelength of 365 nm and a power of 10 W in a nitrogen environment. In order to comprehensively evaluate the variation law of the performance of the solar cells over time, the J-V characteristic curve parameters of each solar cell are measured systematically every 250 h using an AM 1.5G standard light source, and the efficiency decay is calculated accordingly. The results are shown in Table 5.

[0056] From the data provided in Table 5, it can be known that after long-term irradiation, the efficiency retention rate of each group of solar cells doped with M reaches more than 85%, and among them, the efficiency retention rate of Group 5 reaches the initial efficiency of 92.5%; in contrast, the performance of the untreated control group drops sharply to 67.3%. This result indicates that the M molecule achieves a protection function through a dual-pathway: the large π-conjugated system in its structure can effectively absorb the energy of ultraviolet photons, slowing down the exposure intensity of the perovskite film under ultraviolet light; moreover, this part of the ultraviolet light energy is converted into visible light with better response of the perovskite film, increasing the utilization rate of ultraviolet light by the perovskite film; at the same time, specific functional groups within the molecule preferentially bind to the grain boundaries and surface defect sites, blocking the ion migration channels induced by ultraviolet rays.

[0057] Through the above stability tests, it can be known that by doping M in the perovskite layer, the light response performance and environmental stability of perovskite solar cells can be significantly enhanced, providing important technical support for the development of durable solar cells suitable for outdoor high-intensity light conditions.

[0058] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A perovskite solar cell doped with a pyridinium compound, characterized in that, including a perovskite layer, the perovskite layer including Pb doped therein 2+ and a pyridinium compound; Among them, the molar ratio of the pyridinium compound to Pb 2+ is 1:500 to 3:250; The molecular structural formula of the pyridinium compound is as follows: 。 2. The perovskite solar cell doped with a pyridinium compound according to claim 1, characterized in that, It also includes a substrate, an electron transport layer, a hole transport layer, and a metal electrode layer. The substrate, electron transport layer, perovskite layer, hole transport layer, and metal electrode layer are sequentially arranged longitudinally from bottom to top.

3. The perovskite solar cell doped with a pyridinium compound according to claim 2, characterized in that, The substrate is selected from glass materials doped with fluorine-doped tin oxide.

4. The perovskite solar cell doped with a pyridinium compound according to claim 2, characterized in that, The electron transport layer is selected from titanium dioxide materials.

5. The perovskite solar cell doped with a pyridinium compound according to claim 4, characterized in that, An interface modification layer is provided on the electron transport layer. The interface modification layer is selected from lithium fluoride materials, and the thickness of the interface modification layer is 0.3 - 0.8 nm.

6. The perovskite solar cell doped with a pyridinium compound according to claim 2, characterized in that, The hole transport layer is selected from poly(3-hexylthiophene-2,5-diyl) materials or 2,2',7,7'-tetrakis[N,N-bis(4-methoxyphenyl)amino]-9,9'-spirobifluorene materials.

7. The perovskite solar cell doped with a pyridinium compound according to claim 2, characterized in that, The metal in the metal electrode layer is selected from any one of Au, Ag, and Cu.

8. The perovskite solar cell doped with a pyridinium compound according to claim 7, characterized in that, The thickness of the metal electrode layer is 70 - 80 nm.

9. A method for preparing a perovskite solar cell doped with a pyridinium compound, characterized in that, A perovskite solar cell for preparing a doped pyridinium compound according to any one of claims 2 to 8 includes the following steps: S100. Prepare an electron transport layer on the substrate; S200. After adding formamidinium iodide, methylammonium bromide, cesium iodide, and lead iodide into an organic solvent to dissolve, obtaining a perovskite precursor solution I, adding a pyridinium compound, stirring and dissolving to obtain a perovskite precursor solution II, and spin-coating the perovskite precursor solution II on the electron transport layer by gradient spin-coating to obtain a perovskite layer; S300. Prepare a hole transport layer on the perovskite layer; S400. Deposit a metal on the hole transport layer to obtain a metal electrode layer.

10. The method for preparing a perovskite solar cell doped with a pyridinium compound according to claim 9, characterized in that, In step S200, the organic solvent is selected from dimethylformamide and / or dimethyl sulfoxide.

Images