Carbon-based hole-transport-layer-free Ruddlesden-Popper perovskite solar cell prepared in air environment and preparation method of carbon-based hole-transport-layer-free Ruddlesden-Popper perovskite solar cell
Through the guanidine (GA) second spacer cation doping project, the film quality and phase composition of the RP perovskite film are improved, the film quality and defect density problems of the carbon-based RP perovskite solar cells without hole transport layer prepared in air are solved, and efficient and stable device performance is achieved.
Patent Information
- Application Number
- CN202510941235.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-09
- Publication Date
- 2025-10-10
AI Technical Summary
Carbon-based RP perovskite solar cells without hole transport layer prepared in air have poor film quality, difficult to control crystal orientation and phase composition, and high defect density, which leads to serious carrier recombination and limits device performance.
By adopting the guanidine (GA) second spacer cation doping project, the film quality and phase composition of RP perovskite films were improved, the defect density was reduced, and carbon-based RP perovskite solar cells without hole transport layer were prepared.
The efficient preparation of carbon-based RP perovskite solar cells without hole transport layer in air improves the stability and performance of the device and reduces production costs. The PCE can reach up to 11.43% and maintain 72% of the initial efficiency after 1300h.
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Figure CN120769682A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of perovskite solar cells, and in particular to a low-cost carbon-based Ruddlesden–Popper perovskite solar cell without a hole transport layer prepared in an air environment and a preparation method thereof. Background Art
[0002] The current global energy consumption system is highly dependent on non-renewable resources, and the contradiction between their limited reserves and the growing population and economic needs is becoming increasingly acute. Therefore, it is urgent to develop new renewable energy systems to promote energy structural transformation and coordinate social development with ecological protection. In this context, solar energy, due to its cleanliness, renewability, and widespread distribution, has become a key direction for energy strategic transformation. While traditional silicon-based solar cells are technologically mature, high manufacturing costs and limited raw material supply have severely hampered their further large-scale commercial application. Therefore, the development of new, efficient, and low-cost solar cell materials has become a hot topic of research. In recent years, perovskite solar cells, due to their low production cost, high efficiency, and simple fabrication, have been considered one of the most promising new photovoltaic technologies for achieving low-cost power generation. Since their development in 2009, their photoelectric conversion efficiency (PCE) has significantly improved in just a few years. Their industrialization has also gradually expanded in recent years, making them considered one of the most promising photovoltaic cells for development and attracting considerable attention and research.
[0003] Despite the rapid development of perovskite solar cells, the organic cations in typical three-dimensional (3D) organic-inorganic hybrid halide perovskites have disadvantages such as hydrophilicity, thermal instability, and low ion migration activation energy. These disadvantages make these materials sensitive to environmental factors such as water, heat, ultraviolet light, and oxygen, and prone to phase transitions, ion migration, or degradation. This leads to poor stability of perovskite solar cells and is the primary factor limiting their commercialization. Compared to halide perovskites with 3D crystal structures, low-dimensional layered organic-inorganic hybrid halide perovskites have inorganic layers and organic amine layers separated by a natural multi-layer quantum well structure, resulting in better stability than traditional 3D perovskites.
[0004] Furthermore, achieving a high PCE in a fully constructed cell device requires the standard use of organic hole transport materials and metal (Ag or Au) electrodes. These materials are not only expensive but also unstable in ambient air, accelerating device efficiency degradation and increasing production costs. The sensitivity of the perovskite layer and the organic hole transport layer to air necessitates the fabrication of perovskite solar cells in an inert atmosphere glove box, and the fabrication conditions (water, oxygen content, temperature, etc.) must be strictly controlled, further hindering the low-cost commercialization of perovskite solar cells. Carbon materials offer advantages such as low cost, stable chemical properties, good conductivity, strong hole extraction capabilities, and suitability for fabrication by simple blade coating in air. In recent years, research on their use as counter electrodes in 3D perovskite solar cells without a hole transport layer has yielded significant results, significantly improving device stability and reducing production costs.
[0005] Based on the advantages of carbon-based hole-transport-layer device structure and low-dimensional halide perovskite, the preparation of carbon-based hole-transport-layer RP perovskite solar cells with low-dimensional halide perovskite (Ruddlesden-Popper, RP type) as the active layer is expected to significantly improve the stability of the device and reduce production costs. This has important practical significance for promoting the further development and commercialization of perovskite solar cells. However, the current research on carbon-based hole-transport-layer RP perovskite solar cells prepared in air is almost at a blank stage. The biggest challenge is that the film quality of RP perovskite films prepared in air is poor, the crystallization direction and phase composition are difficult to control, and the defect density is high, resulting in serious carrier recombination, which restricts the PCE of carbon-based hole-transport-layer RP perovskite solar cells prepared in air. Summary of the Invention
[0006] In response to the above problems, the present invention provides a method for preparing low-cost carbon-based low-dimensional perovskite solar cells without a hole transport layer in an air environment. Through the guanidine (GA) second spacer cation doping project, the film formation quality of the RP perovskite film prepared in the air is improved, the phase composition is optimized, the film defect density is reduced, and the carrier recombination is effectively suppressed, thereby realizing the preparation of efficient carbon-based RP perovskite solar cells without a hole transport layer in the air.
[0007] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:
[0008] A method for preparing a low-cost carbon-based RP perovskite solar cell without a hole transport layer in an air environment comprises the following steps:
[0009] S1. Cleaning of fluorine-doped tin oxide (FTO) conductive glass substrate: ultrasonically clean the FTO conductive glass with conductive glass detergent, deionized water, acetone, isopropyl alcohol, and anhydrous ethanol for 40 minutes, respectively. After ultrasonic cleaning, soak the FTO conductive glass in anhydrous ethanol for storage. Rinse with deionized water and anhydrous ethanol in turn, blow dry, and then use an ultraviolet ozone (UV) cleaner for 20 minutes.
[0010] S2. Preparation of tin dioxide (SnO2) electron transport layer: First, prepare SnO2 precursor solution, then spin-coat the precursor solution on the FTO conductive glass surface and anneal to obtain the electron transport layer;
[0011] S3. Preparation of RP perovskite active layer: preparing a spacer cation-doped RP perovskite precursor solution, spin-coating the prepared perovskite precursor solution on the surface of the SnO2 electron transport layer and adding an anti-solvent, followed by annealing to obtain a perovskite layer;
[0012] S4. Preparation of carbon electrode: carbon slurry is scraped onto the prepared perovskite film substrate and heat-treated and solidified to obtain a carbon electrode.
[0013] Preferably, both S2 and S3 are spin-coated by a spin coater.
[0014] Preferably, the electron transport material is a SnO2 electron transport layer precursor solution obtained by diluting 15wt% tin dioxide (SnO2) aqueous dispersion in deionized water at a volume ratio of 1:3, which is spin-coated on an FTO conductive glass substrate at a spin coating speed of 3000 rpm. After spin coating, it is annealed at 170°C for 30 minutes to obtain a SnO2 electron transport layer.
[0015] Preferably, the RP type perovskite molecular formula is A'2A (n-1) B n X 3n+1 , where n is 10, A' is an organic spacer cation cyclohexylmethylamine ion (CMA) and GA, A is formamidinium ion (FA) and methylamine ion (MA), and B is lead ion (Pb 2+ ), X is iodide ion (I - ).
[0016] Preferably, the spacer cation-doped RP perovskite precursor solution is prepared by mixing an organic spacer cation source, methylamine iodide (MAI), formamidine iodide (FAI) and lead iodide (PbI2) in a molar ratio of 2:2.7:6.3:10, adding the mixture to a mixed solvent of dimethyl sulfoxide (DMSO) and N,N-dimethylformamide (DMF) in a volume ratio of 1:4, and stirring at room temperature for 12 hours to obtain the RP perovskite precursor solution.
[0017] Preferably, the organic spacer cation sources in the perovskite precursor solution are cyclohexylmethylamine iodide (CMAI) and guanidine chloride (GACl), and the optimal doping molar ratio of GA spacer cations is: CMA:GA=3:2.
[0018] Preferably, the perovskite precursor solution is spin-coated in two steps: the spin-coating speed of the first stage is 1000 rpm, and the spin-coating time is 10s; the spin-coating speed of the second stage is 5000 rpm, and the spin-coating time is 25s, and the anti-solvent is added in the last 10s of the second spin-coating stage, and the anti-solvent must be added within 1-3s. After the spin coating is completed, the RP perovskite active layer is annealed at 150°C for 5-7min to obtain.
[0019] Preferably, the anti-solvent is ethyl acetate.
[0020] Preferably, the carbon paste is a conductive carbon paste, and a high-temperature mask tape is used to cover the non-electrode functional area of the perovskite film substrate. The carbon paste is deposited on the unmasked area by a doctor blade coating method, and cured at 100°C for 20 minutes. The high-temperature mask tape is removed to complete the preparation of the carbon-based RP perovskite solar cell without a hole transport layer.
[0021] Preferably, the processes are all carried out in an air environment with a temperature of ≈20°C±5°C and a humidity of ≈30%±15%.
[0022] Compared with the prior art, the present invention has the following beneficial effects:
[0023] 1. The carbon-based RP perovskite solar cell without a hole transport layer provided by the present invention enhances the stability of the 3D perovskite active layer through low-dimensional perovskite material design. The simplified structure of the carbon-based RP perovskite without a hole transport layer eliminates the need for a hole transport layer and precious metal electrodes, making the device suitable for fabrication in an air environment. This significantly reduces production costs while potentially enhancing device stability. Therefore, the battery device provided by the present invention combines the advantages of both materials and device structure, theoretically possessing excellent stability.
[0024] 2. Aiming at the problem of poor quality and high defect density of RP perovskite films prepared in air, the present invention improves the film quality of RP perovskite films prepared in air by regulating the doping ratio of GA through the GA second spacer cation doping project, optimizes the phase composition, reduces the film defect density, effectively inhibits carrier recombination, and improves the carbon-based hole-free transport layer RP perovskite (CMA2 (MA 0.3 FA 0.7 )9Pb 10 I 31) solar cell performance. Through experimental testing, the device efficiency and repeatability after optimization of GA second spacer cation doping were improved, with the PCE reaching up to 11.43% in air (temperature: 15-25°C, humidity: 15%-35%).
[0025] After 1300 hours of storage, the efficiency can still maintain 72% of the initial efficiency.
[0026] 3. The method of the present invention is prepared in air, has a simple process, avoids dependence on inert gas, and is low in cost. BRIEF DESCRIPTION OF THE DRAWINGS
[0027] Figure 1 Schematic diagram of the device structure of the carbon-based RP perovskite solar cell without a hole transport layer of the present invention;
[0028] Figure 2 (GA obtained in Example 1 0.4 CMA 0.6 )2(MA 0.3 FA 0.7 )9Pb 10 I 31 SEM image of RP perovskite film;
[0029] Figure 3 CMA2 (MA2) obtained in Comparative Example 1 0.3 FA 0.7 )9Pb 10 I 31 SEM image of RP perovskite film;
[0030] Figure 4 For comparative example 2, GA2(MA 0.3 FA 0.7 )9Pb 10 I 31 SEM image of RP perovskite film;
[0031] Figure 5 XRD patterns of the RP perovskite films obtained in Example 1, Comparative Example 1, and Comparative Example 2;
[0032] Figure 6 The UV-visible absorption spectra of the RP perovskite films obtained in Example 1, Comparative Example 1 and Comparative Example 2;
[0033] Figure 7 JV curves of carbon-based RP perovskite solar cells without hole transport layer in Example 1, Comparative Example 1 and Comparative Example 2;
[0034] Figure 8The dark state JV curves of carbon-based RP perovskite solar cells without hole transport layer of Example 1, Comparative Example 1 and Comparative Example 2 are shown;
[0035] Figure 9 PCE distribution of carbon-based RP perovskite solar cells without hole transport layer in Example 1, Comparative Example 1 and Comparative Example 2;
[0036] Figure 10 Schematic diagram of the stability of carbon-based RP perovskite solar cells without hole transport layer in Example 1, Comparative Example 1 and Comparative Example 2. DETAILED DESCRIPTION
[0037] In order to help people in the relevant technical field better understand the content of the patent of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. In the present invention, unless otherwise specified, the raw materials used are products well known to relevant technical personnel in the field and available on the market. This embodiment is implemented under the premise of the technical solution of the present invention, and a detailed implementation method and specific operation process are given.
[0038] Example 1
[0039] The present invention provides a low-cost carbon-based RP perovskite solar cell without a hole transport layer prepared in an air environment, and the device structure diagram is shown as follows: Figure 1 As shown, the specific preparation process is as follows:
[0040] S1. Cleaning of FTO conductive glass substrate: ultrasonically clean the FTO conductive glass with conductive glass detergent, deionized water, acetone, isopropyl alcohol and anhydrous ethanol for 40 minutes respectively. After ultrasonic cleaning, soak it in anhydrous ethanol for storage. Rinse it with deionized water and anhydrous ethanol in turn, blow dry it, and then use an ultraviolet ozone (UV) cleaning machine for 20 minutes;
[0041] Preparation of S2, SnO2 electron transport layer: The electron transport material is spin-coated on the surface of FTO conductive glass. The electron transport material is a SnO2 electron transport layer precursor solution obtained by diluting 15wt% SnO2 aqueous dispersion in deionized water at a volume ratio of 1:3. The solution is spin-coated on the FTO conductive glass substrate at a spin coating speed of 3000 rpm. After spin coating, it is annealed at 170°C for 30 minutes to obtain a SnO2 electron transport layer.
[0042] S3, Preparation of RP perovskite active layer: a perovskite precursor solution is prepared by mixing an organic spacer cation source, MAI, FAI and PbI2 in a molar ratio of 2:2.7:6.3:10 (wherein the organic spacer cation source is selected from CMAI and GACl, and the optimal molar ratio of spacer cation doping is CMA:GA=3:2), and stirring in a mixed solvent of DMSO and DMF in a volume ratio of 1:4 for 12 h to obtain the perovskite precursor solution. The prepared perovskite precursor solution is filtered and uniformly spin-coated on the surface of the electron transport layer, and an anti-solvent ethyl acetate is added to obtain a perovskite wet film. Specifically, two-step spin coating is performed, the first stage is spin-coated at a speed of 1000 rpm for 10 s; the second stage is spin-coated at a speed of 5000 rpm for 25 s, and the anti-solvent is added dropwise in the last 10 s of the second spin-coating stage. The anti-solvent needs to be added dropwise within 1-3 s. After spin coating, the RP perovskite active layer is obtained by annealing at a temperature of 150°C for 5-7 min. The perovskite molecular formula is (GA 0.4 CMA 0.6 )2(MA 0.3 FA 0.7 )9Pb 10 I 31 .
[0043] S4, Preparation of carbon electrode: a high-temperature mask tape is used to cover the non-electrode functional area of the prepared perovskite film substrate, and a conductive carbon paste is deposited on the unmasked area by doctor blade coating method. The carbon electrode is obtained by curing at 100°C for 20 min, and removing the high-temperature mask tape, thereby completing the preparation of the carbon-based hole-free transport layer RP perovskite solar cell.
[0044] Comparative Example 1
[0045] In Reference Example 1, under the process conditions prepared in Example 1, the perovskite precursor solution prepared in step S3 is mixed in a molar ratio of 2:2.7:6.3:10 by CMAI, MAI, FAI and PbI2, and the perovskite molecular formula obtained is CMA2(MA 0.3 FA 0.7 )9Pb 10 I 31 , and the other processes are the same as those in Example 1.
[0046] Comparative Example 2
[0047] In Reference Example 1, under the process conditions prepared in Example 1, the perovskite precursor solution prepared in step S3 is mixed in a molar ratio of 2:2.7:6.3:10 by GACl, MAI, FAI and PbI2, and the perovskite molecular formula obtained is GA2(MA 0.3 FA 0.7 )9Pb10 I 31 , other processes are the same as in Example 1.
[0048] Morphology and crystallinity test:
[0049] Figure 2 (GA prepared in Example 1 0.4 CMA 0.6 )2(MA 0.3 FA 0.7 )9Pb 10 I 31 SEM images of perovskite films, according to Figure 2 It can be seen that the grain arrangement of the RP perovskite film in this embodiment is regular, the grain size is relatively uniform, and the density of the film is good. This may be because the introduction of GA can reduce the erosion of water during grain growth, inhibit the formation of defects caused by water, and form an effective hydrophobic layer in the film, thereby improving the film quality.
[0050] Figure 3 CMA2 (MA prepared in Comparative Example 1 0.3 FA 0.7 )9Pb 10 I 31 SEM images of perovskite films, according to Figure 3 It can be seen that the surface morphology of Comparative Example 1 shows many pinholes and small particles, and the crystallinity is poor.
[0051] Figure 4 GA2 (MA prepared in Comparative Example 2 0.3 FA 0.7 )9Pb 10 I 31 SEM images of perovskite films, according to Figure 4 It can be seen that the grains of Comparative Example 2 are irregular, large and small grains are staggered, and the film is uneven.
[0052] Figure 5 The XRD patterns of the RP perovskite films obtained in Example 1, Comparative Example 1 and Comparative Example 2 are shown in FIG. Figure 5It can be seen that the (111) and (202) diffraction peak intensities of Example 1 are significantly enhanced compared with those of Comparative Example 1 and Comparative Example 2, indicating that the RP perovskite film obtained in Example 1 has better crystallinity; the diffraction peak appearing at ~8.05° in Comparative Example 1 indicates a 2D low n-value RP perovskite phase crystallized parallel to the substrate. The presence of too much 2D low n-value RP perovskite phase will hinder the transport of carriers; in Example 1, the diffraction peak disappears, indicating that the phase composition in Example 1 has been optimized and the 2D low n-value RP perovskite phase has been reduced; the diffraction peak intensities of Comparative Example 2 are very low, indicating that the crystallinity of the film is poor. In addition, a yellow δ-FAPbI3 phase appears at ~11.70° in Comparative Example 2. This species is an inactive perovskite phase, and its appearance is not conducive to the stability and photovoltaic performance of the film.
[0053] Absorbance and phase composition tests:
[0054] Figure 6 The UV-visible absorption spectra of the RP perovskite films obtained in Example 1, Comparative Example 1 and Comparative Example 2 are shown in Table 1. Figure 6 It can be seen that the light absorption performance of Example 1 is significantly better than that of Comparative Example 1 and Comparative Example 2; in Comparative Example 1, an obvious low-n value (n=2) RP perovskite phase appears at ~570 nm, and the intensity of this absorption peak weakens in Example 1, indicating that the low-n value RP perovskite phase in Example 1 is reduced; in Comparative Example 2, there are multiple absorption peaks in the wavelength range of 500-700 nm, indicating that the phase composition in Comparative Example 2 is complex and chaotic, and an absorption peak of the yellow δ-FAPbI3 phase appears at ~470 nm, which is consistent with the conclusion of XRD.
[0055] Photoelectric performance test:
[0056] Figure 7 The JV curves of the carbon-based RP perovskite solar cells without hole transport layer of Example 1, Comparative Example 1 and Comparative Example 2 are shown. Figure 7 It can be seen that the open circuit voltage (V oc ), short-circuit current density (J sc ) and PCE were improved, and the PCE of Example 1 reached 11.43%, which shows that the use of GA as the second spacer cation doping in Example 1 improved the CMA2 (MA 0.3 FA 0.7 )9Pb 10 I 31 The quality of the perovskite film enables Example 1 to exhibit excellent photovoltaic performance.
[0057] Figure 8The dark state JV curves of the carbon-based RP perovskite solar cells without hole transport layer of Example 1, Comparative Example 1 and Comparative Example 2 show that the dark current density of the device in Example 1 is lower than those in Comparative Examples 1 and 2, which indicates that the defect density in Example 1 is reduced, carrier recombination is suppressed, and charge extraction is improved.
[0058] Figure 9 This is a PCE distribution diagram of the carbon-based RP perovskite device without a hole transport layer in Example 1, Comparative Example 1 and Comparative Example 2. It can be seen from the figure that the device has good repeatability, and the repeatability of Example 1 is significantly improved.
[0059] Figure 10 This is a schematic diagram of the stability of the carbon-based hole-free transport layer RP of the perovskite device in Example 1, Comparative Example 1 and Comparative Example 2. It can be seen that Example 1 has higher stability than Comparative Examples 1 and 2. After being placed in the air (temperature: 15-25°C, humidity: 15%-35%) for 1300 hours, the efficiency can still maintain 72% of the initial efficiency.
[0060] The excellent performance of carbon-based hole-transport-free RP perovskite solar cells in Example 1 is due to the following: through the organic spacer cation doping strategy, the introduction of GA second spacer cations can synergize with CMA spacer cations to improve the crystallization process of the RP perovskite film, optimize the film phase composition, inhibit the appearance of low-n-value RP perovskite phase and yellow δ-FAPbI3 phase, reduce defect density, and inhibit non-radiative recombination of carriers, thereby improving PCE. GA has certain chemical stability and antioxidant properties, which can protect the perovskite structure from erosion by external environmental factors (such as moisture, oxygen, etc.); CMA, due to its hydrophobicity, can form a protective film on the surface of the perovskite film to prevent the intrusion of moisture and oxygen. At the same time, its combined action with GA enhances the interlayer interaction, making the layered structure of the perovskite more stable, inhibiting ion migration and lattice deformation, thereby improving the performance stability of the battery during long-term use.
[0061] The preferred embodiments disclosed above are only used to illustrate the technical solutions of the present invention, and are not intended to limit the scope of protection. They do not exclude reasonable improvements made by those skilled in the art based on the principles of the present invention. In short, if those skilled in the art are inspired by them and do not deviate from the purpose of the present invention, they can creatively design structures and embodiments similar to the technical solutions, which should fall within the scope of protection of the present invention.
Claims
1. A low-cost carbon-based Ruddlesden–Popper (RP) perovskite solar cell without a hole transport layer prepared in an air environment, characterized in that: The following steps are involved: S1. Cleaning of fluorine-doped tin oxide (FTO) conductive glass substrate: ultrasonically clean the FTO conductive glass with conductive glass detergent, deionized water, acetone, isopropyl alcohol, and anhydrous ethanol for 40 minutes, respectively. After ultrasonic cleaning, soak the FTO conductive glass in anhydrous ethanol for storage. Rinse with deionized water and anhydrous ethanol in turn, blow dry, and then use an ultraviolet ozone (UV) cleaner for 20 minutes. Preparation of S2, SnO2 electron transport layer: First, prepare SnO2 precursor solution, then spin-coat the precursor solution on the FTO conductive glass surface and anneal to obtain the electron transport layer; S3. Preparation of RP perovskite active layer: preparing a spacer cation-doped RP perovskite precursor solution, spin-coating the prepared perovskite precursor solution on the surface of the SnO2 electron transport layer and adding an anti-solvent, followed by annealing to obtain a perovskite layer; S4. Preparation of carbon electrode: carbon slurry is scraped onto the prepared perovskite film substrate and heat-treated and solidified to obtain a carbon electrode.
2. The preparation method according to claim 1, characterized in that The electron transport material is a SnO2 electron transport layer precursor solution obtained by diluting 15wt% tin dioxide (SnO2) aqueous dispersion in deionized water at a volume ratio of 1:
3. The solution is spin-coated on an FTO conductive glass substrate at a spin-coating speed of 3000 rpm. After spin coating, the solution is annealed at 170°C for 30 minutes to obtain a SnO2 electron transport layer.
3. The preparation method according to claim 1, characterized in that The RP type perovskite molecular formula is A'2A (n-1) B n X 3n+1 , where n is 10, A' is an organic spacer cation cyclohexylmethylamine ion (CMA) and GA, A is formamidinium ion (FA) and methylamine ion (MA), and B is lead ion (Pb 2+ ), X is iodide ion (I - ).
4. The preparation method according to claim 1, characterized in that The spacer cation-doped RP perovskite precursor solution is prepared by mixing an organic spacer cation source, methylamine iodide (MAI), formamidine iodide (FAI) and lead iodide (PbI2) in a molar ratio of 2:2.7:6.3:10, adding the mixture to a mixed solvent of dimethyl sulfoxide (DMSO) and N,N-dimethylformamide (DMF) in a volume ratio of 1:4, and stirring at room temperature for 12 hours to obtain the RP perovskite precursor solution.
5. The preparation method according to claim 1, characterized in that The organic spacer cation sources in the perovskite precursor solution are cyclohexylmethylamine iodide (CMAI) and guanidine chloride (GACl), and the optimal doping molar ratio of GA spacer cation is: CMA:GA=3:
2.
6. The preparation method according to claim 1, characterized in that The perovskite precursor solution is spin-coated in two steps, with the spin-coating speed of the first stage being 1000 rpm and the spin-coating time being 10 s; the spin-coating speed of the second stage being 5000 rpm and the spin-coating time being 25 s, and the anti-solvent is added dropwise in the last 10 s of the second spin-coating stage, and the anti-solvent needs to be added dropwise within 1-3 s. After the spin-coating is completed, the RP perovskite active layer is obtained by annealing at 150°C for 5-7 min, wherein the anti-solvent is ethyl acetate.
7. The preparation method according to claim 1, characterized in that The carbon paste is a conductive carbon paste, which is covered on the non-electrode functional area of the perovskite film substrate with a high-temperature mask tape. The carbon paste is deposited on the unmasked area by a doctor blade coating method, and cured at 100°C for 20 minutes. The high-temperature mask tape is removed to complete the preparation of the carbon-based RP perovskite solar cell without a hole transport layer.
8. The preparation method according to claim 1, characterized in that The above processes are all carried out in an air environment with a temperature of ≈20°C±5°C and a humidity of ≈30%±15%.