Perovskite solar cell based on perfluoro self-assembly molecules as interface modification layer and preparation method thereof

Abstract

The invention relates to a perovskite solar cell based on a perfluoro self-assembly molecule as an interface modification layer and a preparation method thereof. The perovskite solar cell sequentially comprises a conductive light-transmitting substrate, a hole transport layer, an interface modification layer, a perovskite light absorption layer, an interface passivation layer, an electron transport layer, a hole barrier layer and a metal electrode layer from bottom to top, wherein the interface modification layer is a complete layer jointly formed by perfluoro self-assembly molecules and other self-assembly molecules, and the perfluoro self-assembly molecules are selected from at least one of perfluoro (2-methyl-3-oxa) hexanoic acid, perfluoro-2, 5-dimethyl-3, 6-dioxaheptanoic acid, perfluorooctane carboxylic acid and perfluorooctane phosphonic acid. According to the invention, the perfluoro self-assembly molecules can inhibit the longitudinal accumulation of other self-assembly molecules, so that the self-assembly molecules can cover the substrate more uniformly and completely to inhibit the harmful reaction of a buried bottom interface, passivate interface defects, reduce non-radiative recombination and the like, thereby greatly improving the energy conversion efficiency and stability of the perovskite solar cell.

Description

Technical Field

[0001] This invention relates to the field of perovskite solar cell technology, specifically to a perovskite solar cell based on a perfluorinated self-assembled molecule as an interface modification layer and its preparation method. Background Technology

[0002] Perovskite solar cells possess excellent photoelectric properties, including high absorption coefficients, direct bandgap band structures, long carrier lifetimes, and tunable bandgap widths. They also offer advantages such as simple fabrication processes and low cost, making them one of the leading devices in third-generation solar cells. Currently, the highest power conversion efficiency of single-junction perovskite cells has exceeded 27%. However, compared to crystalline silicon, gallium arsenide, and copper indium gallium selenide (CIGS) cells, the commercial application of perovskite photovoltaic devices is hampered by their stability issues.

[0003] In perovskite solar cells, the active layer is connected to a conductive and transparent substrate (the substrate may be rigid glass or a flexible conductive substrate made of polyethylene terephthalate (PET), polyethylene naphthalate (PEN), or polyimide (PI), with a conductive layer on top made of fluorine-doped tin oxide (FTO) or indium-doped tin oxide (ITO)) or a bottom hole transport material (such as NiO). x Interfacial defects, energy level mismatches, and chemical instabilities often exist between perovskite active layers (PTAA, PEDOT:PSS, etc.), severely restricting device efficiency and long-term operational stability, and becoming one of the core challenges in their industrialization. Currently, interface modification using self-assembled molecules is considered an effective solution, capable of improving device photoelectric conversion efficiency to over 25%. Self-assembled molecules can not only regulate interface energy level matching but also effectively suppress unfavorable side reactions at the perovskite substrate interface. However, self-assembled molecules are prone to self-aggregation on the substrate surface, leading to uneven interface contact, vertical stacking, and even dynamic response failure, becoming a significant bottleneck limiting further improvements in device efficiency and stability. Therefore, efficient interface modification of the buried interface between the perovskite active layer and the conductive transparent substrate or hole transport layer has become a key technology for improving device performance and suppressing open-circuit voltage loss, urgently requiring the development of interface modification molecules with high coverage and interface control capabilities.

[0004] To address the aforementioned issues, current methods employ a blending strategy: coating only self-assembled molecules beneath the perovskite light-absorbing layer, or blending self-assembled molecules with other molecular materials to form a self-assembled molecular layer. This leverages the energy level modulation, defect passivation, and interface protection effects of self-assembled molecules, or the blending strategy with other molecular materials, to mitigate the incomplete coverage of the substrate by self-assembled molecules, thereby optimizing energy level alignment, suppressing interfacial side reactions, and reducing non-radiative recombination at the interface. However, the pure self-assembled molecule strategy suffers from several problems: self-aggregation and vertical stacking easily occur on the substrate surface, leading to uneven interfacial contact and hindering the formation of high-quality perovskite films. The blending strategy, on the other hand, presents several issues: multiple molecules already undergo chemical interactions in solution, and other molecular materials lack the stability to anchor themselves to the substrate; uncontrollability arises because the blending technique preferentially mixes self-assembled molecules with other molecular materials in solution, making their precipitation process on the substrate uncontrollable, resulting in randomness in the uniformity of self-assembled molecule coverage. Therefore, the energy conversion efficiency achieved by existing technologies remains below 26%, and the interface is dynamically unstable, leading to poor device stability. Summary of the Invention

[0005] The purpose of this invention is to provide a perovskite solar cell based on a perfluorinated self-assembled molecule as an interface modification layer and its preparation method. The perfluorinated self-assembled molecules suppress the vertical stacking of other self-assembled molecules and ensure a more uniform and complete coverage of the substrate, thereby inhibiting harmful reactions at the buried interface, passivating interface defects, and reducing non-radiative recombination at the interface, ultimately significantly improving the energy conversion efficiency and stability of the perovskite solar cell. More specifically, the perfluorinated self-assembled molecules partially cover the substrate, forming a discrete distribution structure, and then other self-assembled molecules are confined within this structure to form a complete interface modification layer. The perfluorinated self-assembled molecules, through their electrostatic repulsion and the discrete confinement structure they form, suppress the vertical stacking of self-assembled molecules and ensure a more uniform and complete coverage of the substrate. Simultaneously, the interface modification layer formed through this technique strengthens the chemical interaction between the layer and the perovskite substrate interface, making the interface structure more stable and facilitating the control of the crystal growth process of the perovskite light-absorbing layer, ultimately achieving higher photoelectric conversion efficiency and higher stability.

[0006] The technical solution of the invention is as follows: A perovskite solar cell based on a perfluorinated self-assembled molecule as an interface modification layer has one of the following two structures: Structure 1 consists of, from bottom to top, a conductive and transparent substrate, a hole transport layer, an interface modification layer, a perovskite light-absorbing layer, an interface passivation layer, an electron transport layer, a hole blocking layer, and a metal electrode layer. Alternatively, structure two consists of, from bottom to top, a conductive and transparent substrate, an interface modification layer, a perovskite light-absorbing layer, an interface passivation layer, an electron transport layer, a hole blocking layer, and a metal electrode layer. The interface modification layer is composed of perfluorinated self-assembled molecules and other self-assembled molecules, which are arranged alternately on the substrate in a distribution ratio of 1:100-1:1, and the total thickness of the film is 1-4 nm. The perfluorinated self-assembled molecule is selected from at least one of perfluoro(2-methyl-3-oxa)hexanoic acid (PFA), perfluoro-2,5-dimethyl-3,6-dioxaheptanic acid, perfluorooctane carboxylic acid, and perfluorooctylphosphonic acid. The other self-assembled molecules are substance A or substance B; Substance A is one or more of the following: [2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl]phosphonic acid (MeO-2PACz), [2-(3,6-dimethyl-9H-carbazole-9-yl)ethyl]phosphonic acid (Me-2PACz), [4-(3,6-dimethyl-9H-carbazole-9-yl)butyl]phosphonic acid (Me-4PACz), [4-(3,6-diphenyl-9H-carbazole-9-yl)butyl]phosphonic acid (Ph-4PACz), and [4-(7H-dibenzo[c,g]carbazole-7-yl)butyl]phosphonic acid (4PADCB). Substance B is one or more of the following polymers: [2-(3,6-poly-9H-carbazole-9-yl)ethyl]phosphonic acid (poly-2PACz) and [4-(3,6-poly-9H-carbazole-9-yl)butyl]phosphonic acid (poly-4PACz), with a polymer molecular weight between 1,000 and 100,000. The conductive and light-transmitting substrate is made of rigid glass, flexible substrate polyethylene terephthalate (PET), polyethylene naphthalate (PEN), or polyimide (PI), and the light-transmitting and conductive layer on top is made of fluorine-doped tin oxide (FTO, with a thickness of 300-1000 nm) or indium-doped tin oxide (ITO, with a thickness of 50-150 nm). The hole transport layer is made of nickel oxide (NiO). x , x Between 1-2) or polytriarylamine (PTAA), with a film thickness of 2-30 nm; The perovskite light-absorbing layer is composed of an organometallic halide layer, specifically cesium methylamine formamidinium lead iodide bromide (Cs). x MA y FA 1-x-y )Pb(I a Br 1-a )3, of which xThe values ​​are between 0.02 and 0.20, y is between 0.02 and 0.20, a is between 0.60 and 1.00, and the film thickness is 200-1000 nm. The perovskite precursor solution is prepared according to the above components, with the addition of additional additives methylamine hydrochloride (molar ratio 5-35%) and excess lead iodide (molar ratio 0%-10%).

[0007] The interface passivation layer is one or more of 1,3-diaminopropane dihydroiodate (PDAI2), n-octylammonium iodide (n-OAI), piperazine dihydroiodate (PDI), phenylethylammonium iodate (PEAI), and 3-methylthio-1-propylamine hydroiodate (3MPTAI), with a thickness of 1-20 nm. The electron transport layer is [6,6]-phenyl-C61-isomethyl butyrate (PCBM), C 60 C 70 One of them has a film thickness of 10-40 nm; The hole-blocking layer is composed of 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) and tin oxide (SnO). x , x One of the following (between 1.8 and 2.0), with a film thickness of 5-30 nm; The metal electrode layer includes one or more of gold (Au), silver (Ag), copper (Cu) and aluminum (Al), with a thickness of 50-200 nm.

[0008] The interface modification layer improves the contact between the hole transport layer or the transparent conductive substrate and the perovskite layer. The perfluorinated self-assembled molecules, through their electrostatic repulsion and the discrete confinement structure they form, suppress the longitudinal stacking of other self-assembled molecules, resulting in a more uniform and complete coverage of the substrate. Specifically, the initially coated perfluorinated self-assembled molecules do not completely cover the substrate surface, forming a partially continuous discrete distribution structure that separates subsequently coated self-assembled molecules. This means that the perfluorinated self-assembled molecules act as a framework, with other self-assembled molecules occupying the uncovered areas within these compartments. Together, they constitute the complete interface modification layer. The coverage rate of the perfluorinated self-assembled molecules on the substrate is 5-39%, the spacing is 1.0-100 nm, and the thickness is 0.5-2.0 nm. Ultimately, the interface modification layer, composed of perfluorinated self-assembled molecules and other self-assembled molecules, can achieve a coverage rate of 90-100% on the substrate surface.

[0009] The method for preparing perovskite solar cells based on perfluorinated self-assembled molecules as the interface modification layer is one of the following two methods: The preparation of Structure 1 includes the following steps: Step 1: Clean the conductive and transparent substrate in sequence with glass cleaner, deionized water, acetone, isopropanol and ethanol, then soak it in ethanol, blow it dry with nitrogen, and treat it with ultraviolet ozone before use. Step 2: Coat the substrate surface with a hole transport layer dispersion at a concentration of 5-20 mg / mL, and then heat it on a hot stage at 100-120℃ for 5-20 minutes in an air environment with a relative humidity of 10-40% to obtain the hole transport layer. The nickel oxide (NiO) x , x Between 1-2), the solvent of the dispersion is one or more of water, methanol, ethanol, isopropanol, and propanol; 20-100 microliters of hole transport layer dispersion are coated on every 2.0-2.5 square centimeters of substrate; Step 3: In an anhydrous, oxygen-free, and dust-free environment, a perfluorinated self-assembled molecule solution with a concentration of 0.1-1.0 mg / mL is coated onto the hole transport layer, and then heated on a hot stage at 80-120℃ for 5-20 minutes; then, other self-assembled molecule solutions with a concentration of 0.2-2.0 mg / mL are coated onto the interface obtained above to prepare an interface modification layer; The solvent for the solutions of the perfluorinated self-assembled molecules and other self-assembled molecules is the same, namely one or more of water, methanol, ethanol, isopropanol, and propanol; Step 4: In an environment free of water, oxygen, and dust, coat the perovskite precursor solution onto the interface modification layer obtained above, and prepare a perovskite film using the anti-solvent method or vacuum flash evaporation method. The film thickness is 200-1000 nm. After removing the substrate, heat it on a hot stage at 80-120℃ for 20-40 minutes to prepare the perovskite light-absorbing layer. Add 2 to 60 microliters of perovskite precursor solution to every 2.0 to 2.5 square centimeters of substrate; The perovskite precursor solution is prepared according to the composition of the perovskite (Cs). x MA y FA 1-x-y )Pb(I a Br 1-a )3 configuration, in which, xThe solute is between 0.02 and 0.20, y is between 0.02 and 0.20, a is between 0.60 and 1.00, and the solute is several of the following: cesium iodide (CsI), lead iodide (PbI2), formamidinium hydroiodide (FAI), methylamine hydroiodide (MAI), lead bromide (PbBr2), and methylamine hydrobromide (MABr), with the addition of additional additives such as methylamine hydrochloride (MACl) (molar ratio 5-35%) and excess lead iodide (PbI2) (molar ratio 0%-10%), or it can be a directly formed single-crystal perovskite solute. The solvent is a blend of dimethylformamide (DMF) and dimethyl sulfoxide (DMSO), which may include acetonitrile solvent, N-methylpyrrolidone (NMP solvent) and γ-butyrolactone solvent. The solution concentration is in the range of 0.8-1.7 mol / L. Step 5: In an anhydrous, oxygen-free, and dust-free environment, coat the perovskite light-absorbing layer obtained above with an interface passivation layer solution of 0.1-1.0 mg / mL, and then heat it on a hot stage at 80-120℃ for 5-10 minutes to prepare an interface passivation layer with a thickness of 1-20 nm.

[0010] Add 2-60 μL of interface passivation layer solution to every 2.0-2.5 square centimeters of substrate; The interface passivation layer is made of one or two of 1,3-diaminopropane dihydroiodate (PDAI2), n-octylammonium iodide (n-OAI), piperazine dihydroiodate (PDI), phenylethylammonium iodate (PEAI), and 3-methylthio-1-propylamine hydroiodate (3MPTAI), and the solvent is one or more of water, methanol, ethanol, isopropanol, and propanol. Step Six: Spin-coating an electron transport layer or a high-vacuum 10-layer electrode onto the interface passivation layer. -4 Electron transport layers with a thickness of 10-40 nm are prepared by vacuum deposition in environments below Pa. Step 7: Prepare a hole-blocking layer by spin-coating or atomic layer deposition on the electron transport layer, or by high vacuum (10°C). -4 Hole blocking layers with a thickness of 5-30 nm are prepared by vacuum evaporation deposition in environments below Pa. Step 8: High Vacuum 10 -4 The metal electrode layer is deposited in an environment below Pa with a deposition thickness of 50-200 nm. The coating process includes spin coating, blade coating, and slot coating. Alternatively, the preparation of structure two includes the following steps: The other steps are the same as in Method 1, except that there is no step 2. That is, only steps 1, 3 (the difference in this step is that the perfluorinated self-assembled molecule solution with a concentration of 0.1-1.0 mg / mL is directly coated onto the conductive and transparent substrate), 4, 5, 6, 7 and 8 of Method 1 are used in sequence.

[0011] The essential features of this invention are: Current technologies typically employ either a self-assembled monolayer coated beneath the perovskite absorber layer or a blending strategy involving the mixing of self-assembled molecules with other molecular materials to form a self-assembled layer. However, the self-assembled monolayers are prone to self-aggregation and vertical stacking, resulting in incomplete substrate coverage and uneven distribution. This leads to interfacial side reactions and interfacial instability caused by direct contact between the subsequently coated perovskite absorber layer and the substrate. While blending can alleviate the problem of incomplete substrate coverage and uneven distribution of self-assembled molecules, the chemical interactions between various molecules in solution under this strategy mean that other molecular materials lack the stability to anchor themselves to the substrate. Their precipitation process on the substrate is uncontrollable, resulting in randomness in the uniformity of self-assembled molecule coverage, which is detrimental to the formation of high-quality perovskite films. Therefore, devices fabricated using existing technologies exhibit dynamic interfacial instability and poor thermal stability of the perovskite film, limiting further improvements in the efficiency and stability of perovskite solar cells.

[0012] This invention refers to the newly added perfluorinated self-assembled molecules and the self-assembled molecules together as an interface modification layer. First, a discretely distributed confined interface is formed by coating the anchored perfluorinated self-assembled molecules, which are less prone to self-aggregation. This interface promotes uniform coverage of other self-assembled molecules while inhibiting their self-aggregation and vertical stacking, thereby improving the overall uniformity and coverage of the self-assembled molecules on the substrate. Furthermore, the perfluorinated self-assembled molecules can exhibit strong interactions with the perovskite substrate interface. Specifically, the perfluorinated self-assembled molecules can form hydrogen bonds with FAI (formamidinium hydroiodide) in the perovskite component and with Pb in the perovskite. 2+ and I - Coordination and dipole interactions can be formed to enhance the interaction between the perovskite light-absorbing layer and the bottom interface, thereby improving the overall efficiency of the device to 26.84%. After 800 hours of maximum power point tracking under one sun, it can still maintain 94.6% of the initial efficiency, and after being stored at 65°C for 1000 hours, it can still maintain more than 95% of the initial efficiency.

[0013] In summary, this invention can further improve the interfacial contact between the perovskite light-absorbing layer and the substrate, suppress interfacial side reactions, and reduce nonradiative recombination caused by interfacial defects, thereby improving device efficiency and stability.

[0014] The present invention has the following beneficial effects: 1. This invention introduces perfluorinated self-assembled molecules to suppress the vertical stacking of other self-assembled molecules, effectively weakening their self-aggregation behavior and improving their interfacial coverage on the substrate surface. The interfacial modification layer formed by the perfluorinated self-assembled molecules and other self-assembled molecules can achieve 90-100% interfacial coverage, significantly improving the interfacial contact between the perovskite light-absorbing layer and the hole transport layer or conductive transparent substrate, thus helping to increase the photoelectric conversion efficiency of perovskite solar cell devices to 26.84%. 2. In this invention, an interface modification layer composed of perfluorinated self-assembled molecules and other self-assembled molecules is used to effectively block direct contact between the perovskite active layer and the hole transport layer or conductive transparent substrate. This significantly suppresses potential adverse chemical reactions between the perovskite and metal oxides, reduces interfacial nonradiative recombination losses, and thus enhances the stability of the device while improving its efficiency. After 800 hours of maximum power point tracking at 1 sun, it still maintains 94.6% of its initial efficiency. 3. The interface modification layer formed by the present invention has a regulatory effect on the nucleation and crystal growth of perovskite thin films, which helps to achieve uniform deposition and high crystal quality of the thin film, further improves the fill factor of the device to 86.61%, and thus enhances the photoelectric conversion efficiency; 4. In this invention, there is a strong interaction between the perfluorinated self-assembled molecules and the perovskite active layer, which enhances the bonding force at the bottom interface and effectively suppresses the thermal decomposition of the perovskite light-absorbing layer. After being stored at 65°C for 1000 hours, the device still maintains more than 95% of its initial efficiency, demonstrating excellent long-term stability.

[0015] In summary, this invention can significantly improve the energy conversion efficiency and long-term stability of perovskite devices while ensuring low device fabrication costs, thus greatly benefiting the commercialization of perovskite solar cells. Attached Figure Description

[0016] Figure 1 The diagram shows the structures of four perovskite solar cell devices: Control Group 1, Experimental Group 1, Control Group 2, and Experimental Group 2. Figure 1 (a) is a schematic diagram of the structure of the comparative group 1 device without a hole transport layer. Figure 1 (b) is a schematic diagram of the device structure of experimental group 1 without a hole transport layer. Figure 1 (c) is a schematic diagram of the structure of the comparative group 2 device containing a hole transport layer. Figure 1 (d) is a schematic diagram of the device structure of experimental group 2 containing a hole transport layer.

[0017] Figure 2The X-ray photoelectron spectra of the F 1s peak of the devices modified with perfluoro(2-methyl-3-oxahexanoic acid) in the control group device (Control) of Comparative Example 2 and the experimental group device (Target) of Example 2 are shown.

[0018] Figure 3 The X-ray diffraction spectra of other self-assembled molecules in the devices modified with perfluoro(2-methyl-3-oxahexanoic acid) in Comparative Example 2 and Experimental Example 2 are shown.

[0019] Figure 4 The top view (top view) and side view (bottom view) of the equilibrium heterojunction interface structure of the self-assembled molecule Me-4PACz after preferential formation of confined interfaces (target) by PFA molecules on nickel oxide (Control) and its surface are calculated by classical molecular dynamics simulation of the control group device in Comparative Example 2 and the experimental group device in Example 2.

[0020] Figure 5 The image shows the coverage of the self-assembled molecule Me-4PACz on nickel oxide (001) and nickel oxide (001) surfaces with PFA molecules adsorbed on them, based on classical molecular dynamics simulations of the control group device in Comparative Example 2 and the experimental group device in Example 2.

[0021] Figure 6 This is a schematic diagram showing the distribution of the interface modification layer of the self-assembled molecules in the control group of Comparative Example 2 and the device in the experimental group of Example 2.

[0022] Figure 7 This is an in-situ photoluminescence (PL) image of the perovskite light-absorbing layer during spin coating of the control group device in Comparative Example 2.

[0023] Figure 8 This is an in-situ photoluminescence (PL) image of the perovskite light-absorbing layer spin-coating process of the experimental group device in Example 2.

[0024] Figure 9 X-ray photoelectron spectra of the F 1s peak at the perovskite buried interface of the control group device in Comparative Example 2 and the experimental group device in Example 2.

[0025] Figure 10 X-ray photoelectron spectra of the Pb 4f peak at the perovskite buried interface of the control group device in Comparative Example 2 and the experimental group device in Example 2.

[0026] Figure 11 This is a photoluminescence imaging (PLmapping) image of the buried interface of the perovskite light-absorbing layer in the control group device of Comparative Example 2.

[0027] Figure 12 This is a photoluminescence imaging image of the buried interface of the perovskite light-absorbing layer of the experimental device in Example 2.

[0028] Figure 13 This is a scanning electron microscope image of the buried interface of the perovskite light-absorbing layer in the control group device of Comparative Example 2.

[0029] Figure 14 This is a scanning electron microscope image of the buried interface of the perovskite light-absorbing layer of the experimental device in Example 2.

[0030] Figure 15 The X-ray diffraction pattern of the perovskite thin film of the control group device in Comparative Example 2 as a function of time after exposure to 85°C and 40% relative humidity.

[0031] Figure 16 The image shows the X-ray diffraction pattern of the perovskite thin film of the experimental group device in Example 2 as it changes over time when exposed to an environment of 85°C and 40% relative humidity.

[0032] Figure 17 The NH stretching vibration peaks of the attenuated total internal reflection-Fourier transform (ATR-FTIR) of the perovskite and PFA-perovskite blends in Comparative Example 2 and Experimental Example 2 are shown.

[0033] Figure 18 The CF stretching vibration peaks of the attenuated total internal reflection-Fourier infrared transform of the perovskite and PFA-perovskite blends in Comparative Example 2 and Experimental Example 2 are shown.

[0034] Figure 19 The current-voltage curves of the control group device (device A) in Comparative Example 1 are shown.

[0035] Figure 20 The current-voltage curves are for the experimental group device (device B) in Example 1.

[0036] Figure 21 The current-voltage curves of the control group device (device C) in Comparative Example 2 are shown.

[0037] Figure 22 The current-voltage curves of the experimental group device (device D) in Example 2 are shown.

[0038] Figure 23 The current-voltage curves of the experimental group device (device E) in Example 3 are shown.

[0039] Figure 24 The current-voltage curves of the experimental group device (device F) in Example 4 are shown.

[0040] Figure 25 The current-voltage curves of the experimental group device (device G) in Example 5 are shown.

[0041] Figure 26 The current-voltage curves of the experimental group device (device H) in Example 6 are shown.

[0042] Figure 27 The current-voltage curves of the experimental group device (device I) in Example 7 are shown.

[0043] Figure 28 The graphs show the thermal stability test results of device C in Comparative Example 2 and device D in Experimental Example 2 under nitrogen atmosphere and heating at 65°C.

[0044] Figure 29 The figures show the maximum power point stability tracking test results of the control group device C in Comparative Example 2 and the experimental group device D in Example 2 under the illumination of an LED light source with strong sunlight. Detailed Implementation

[0045] Comparative Example 1: The device prepared in this embodiment is the control group, named device A. The structural schematic diagram of control group device A is attached. Figure 1 As shown in (a), the fabrication steps of the ITO glass (1), self-assembled molecular layer (2), perovskite light-absorbing layer (3), interface passivation layer (4), electron transport layer (5), hole blocking layer (6), and metal electrode (7) are as follows: 1. The conductive and light-transmitting substrate (1.5 cm × 1.5 cm in size and 0.7 mm in thickness - all other embodiments below use this size) is cleaned in sequence with glass cleaner, deionized water, acetone, isopropanol and ethanol, then soaked in ethanol, dried with nitrogen, and treated with ultraviolet ozone before use. 2. In an anhydrous, oxygen-free, and dust-free environment, this can generally be achieved using a glove box device. 50 μL of a 0.5 mg / mL solution of self-assembled molecule [4-(3,6-dimethyl-9H-carbazole-9-yl)butyl]phosphonic acid (ethanol as solvent) is coated onto a conductive and transparent substrate to prepare a self-assembled molecular layer with a thickness of 1.1 nm. 3. In an anhydrous, oxygen-free, and dust-free environment, this can generally be achieved using a glove box device. A 50 μL calcium ore precursor solution (obtained by dissolving CsI, FAI, MAI, PbI2, and MACl in a mixed solvent at a molar ratio of 0.075:1.275:0.1497:1.65:0.186 and stirring for 5 h in a DMF and DMSO solution with a volume ratio of 4:1, and the precursor solution chemical composition is CsI…) is typically achieved through spin-coating on the substrate using a glove box device. 0.05 FA 0.85 MA 0.1PbI3), spin-coated at 1000 rpm for 10 s, followed by 5000 rpm for 30 s. Using the anti-solvent method, 120 μL of chlorobenzene was injected with a pipette or dropper at the 20th s of the 5000 rpm process. After removing the substrate, it was heated on a hot stage at 100℃ for 30 minutes, with a thickness of 790 nm. 4. An interface passivation layer was prepared on the surface of the perovskite light-absorbing layer. Specifically, during the 5th second of the substrate rotation at 4000 rpm for 30 seconds, 25 μL of phenylethylammonium iodate (PEAI) interface passivation layer solution (concentration of 2 mg / mL, solvent of isopropanol) was pipetted onto the center of the substrate by rotating and dropping. The drop height was limited to 0.5 cm. After the drop was completed, the substrate was heated on a hot stage at 100℃ for 10 min, and the thickness was 1.5 nm. 5. High vacuum 10 -4 C is prepared by vacuum deposition in environments below Pa. 60 An electron transport layer with a thickness of 25 nm; 6. High vacuum 10 -4 A hole-blocking layer with a thickness of 6.5 nm was prepared by vacuum deposition in an environment below Pa. 7. High vacuum 10 -4 Ag metal electrode layers are deposited in an environment below Pa, with the deposition environment maintained below 50°C, and the deposition thickness is 150 nm.

[0046] The performance of the fabricated perovskite solar cells was tested using a solar intensity simulator, and the results are shown in the attached figure. Figure 19 The current is 25.30 mA / cm. 2 The opening voltage is 1114 mV, the fill factor is 64.82%, and the energy conversion efficiency is 18.27%.

[0047] Example 1: The device prepared in this embodiment is the experimental group, named device B. The structural schematic diagram of experimental group device B is attached. Figure 1 As shown in (b), the structure consists of ITO glass (1), an interface modification layer (8), a perovskite light-absorbing layer (3), an interface passivation layer (4), an electron transport layer (5), a hole blocking layer (6), and a metal electrode (7). The preparation steps are as follows: 1. Clean the conductive and light-transmitting substrate (1.5 cm × 1.5 cm in size and 0.7 mm in thickness) in sequence with glass cleaner, deionized water, acetone, isopropanol and ethanol, then soak it in ethanol, blow it dry with nitrogen, and treat it with ultraviolet ozone before use. 2. In an anhydrous, oxygen-free, and dust-free environment, using a glove box apparatus, 50 μL of a 0.25 mg / mL perfluoro(2-methyl-3-oxa)hexanoic acid solution (ethanol as solvent) was coated onto a conductive and transparent substrate, and then heated on a hot stage at 100°C for 10 minutes; then 50 μL of a 0.5 mg / mL solution of other self-assembled molecules [4-(3,6-dimethyl-9H-carbazole-9-yl)butyl]phosphonic acid (ethanol as solvent) was coated onto the interface obtained above to prepare an interface modification layer with a thickness of 1.3 nm; 3. In an anhydrous, oxygen-free, and dust-free environment, using a glove box apparatus, 50 μL of perovskite precursor solution (obtained by dissolving CsI, FAI, MAI, PbI2, and MACl in a mixed solvent at a molar ratio of 0.075:1.275:0.1497:1.65:0.186 and stirring for 5 h in a mixed solvent of DMF and DMSO solutions with a volume ratio of 4:1, and the precursor solution having a chemical composition of CsI, FAI, MAI, PbI2, and MACl) was spin-coated onto a substrate. 0.05 FA 0.85 MA 0.1 PbI3), spin-coated at 1000 rpm for 10 s followed by 5000 rpm for 30 s. Using the anti-solvent method, 120 μL of chlorobenzene was injected with a pipette or dropper at the 20th s of the 5000 rpm process. After removing the substrate, it was heated on a hot stage at 100℃ for 30 minutes to achieve a thickness of 790 nm. 4. An interface passivation layer was prepared on the surface of the perovskite light-absorbing layer. Specifically, 25 μL of PEAI interface passivation layer (concentration of 2 mg / mL, solvent of isopropanol) was pipetted on the substrate at the 5th second of the substrate rotation at 4000 rpm for 30 s. The layer was dropped onto the center of the substrate by rotating and dropping, with the drop height limited to 0.5 cm. After the drop was completed, the substrate was heated on a hot stage at 100℃ for 10 min, with a thickness of 1.5 nm. 5. High vacuum 10 -4 C is prepared by vacuum deposition in environments below Pa. 60 An electron transport layer with a thickness of 25 nm; 6. High vacuum 10 -4 A hole-blocking layer with a thickness of 6.5 nm was prepared by vacuum deposition in an environment below Pa. 7. High vacuum 10 -4 Ag metal electrode layers are deposited in an environment below Pa, with the deposition environment maintained below 50°C, and the deposition thickness is 150 nm.

[0048] The performance of the fabricated perovskite solar cells was tested using a solar intensity simulator, and the results are shown in the attached figure. Figure 20 The current is 25.30 mA / cm. 2The opening voltage is 1131 mV, the fill factor is 81.32%, and the energy conversion efficiency is 23.27%.

[0049] Comparative Example 2: The device prepared in this embodiment is the control group, named device C. The structural schematic diagram of control group device C is attached. Figure 1 As shown in (c), the structure consists of ITO glass (1), a hole transport layer (9), a self-assembled molecular layer (2), a perovskite light-absorbing layer (3), an interface passivation layer (4), an electron transport layer (5), a hole blocking layer (6), and a metal electrode (7). The preparation steps are as follows: 1. Clean the conductive and light-transmitting substrate (1.5 cm × 1.5 cm in size and 0.7 mm in thickness) in sequence with glass cleaner, deionized water, acetone, isopropanol and ethanol, then soak it in ethanol, blow it dry with nitrogen, and treat it with ultraviolet ozone before use. 2. Coat the substrate surface with 50 μL of nickel oxide (NiO) at a concentration of 10 mg / mL. x , x The nickel oxide hole transport layer with a thickness of 4 nm was prepared by heating the dispersion in 1-2) on a hot stage at 100°C for 10 minutes in an air environment with a relative humidity of 10-40% on an air environment. 3. In an anhydrous, oxygen-free, and dust-free environment, this can generally be achieved using a glove box device, by coating NiO with a 50 μL solution of a 0.5 mg / mL self-assembled molecular [4-(3,6-dimethyl-9H-carbazole-9-yl)butyl]phosphonic acid (ethanol as solvent). x A self-assembled molecular layer with a thickness of 1.1 nm was prepared on the thin film. 4. In an anhydrous, oxygen-free, and dust-free environment, this can generally be achieved using a glove box device. 50 μL of perovskite precursor solution (obtained by dissolving CsI, FAI, MAI, PbI2, and MACl in a mixed solvent at a molar ratio of 0.075:1.275:0.1497:1.65:0.186 and stirring for 5 h in a DMF and DMSO solution with a volume ratio of 4:1, and the precursor solution chemical composition is CsI…) is… 0.05 FA 0.85 MA 0.1 PbI3), spin-coated at 1000 rpm for 10 s, followed by 5000 rpm for 30 s. Using the anti-solvent method, 120 μL of chlorobenzene was injected with a pipette or dropper at the 20th s of the 5000 rpm process. After removing the substrate, it was heated on a hot stage at 100℃ for 30 minutes, with a thickness of 790 nm. 5. An interface passivation layer was prepared on the surface of the perovskite light-absorbing layer. Specifically, during the 5th second of the substrate rotation at 4000 rpm for 30 seconds, 25 μL of PEAI interface passivation layer solution (concentration of 2 mg / mL, solvent of isopropanol) was pipetted onto the center of the substrate by rotating and dropping. The drop height was limited to 0.5 cm. After the drop was completed, the substrate was heated on a hot stage at 100℃ for 10 min, and the thickness was 1.5 nm. 6. High vacuum 10 -4 C is prepared by vacuum deposition in environments below Pa. 60 An electron transport layer with a thickness of 25 nm; 7. High vacuum 10 -4 A hole-blocking layer with a thickness of 6.5 nm was prepared by vacuum deposition in an environment below Pa. 8. High vacuum 10 -4 Ag metal electrode layers are deposited in an environment below Pa, with the deposition environment maintained below 50°C, and the deposition thickness is 150 nm.

[0050] After step 2 of the preparation process is completed, a sample is taken for X-ray photoelectron spectroscopy (XPS) analysis. The results are shown in the attached figure. Figure 2 (Control group) No fluorine was detected on the surface of the hole transport layer. After step 3 of preparation, samples were taken for X-ray diffraction analysis; the results are attached. Figure 3 (Control group) Other self-assembled molecules exhibit longitudinally stacked diffraction peaks. The top view (top image) and side view (bottom image) of the self-assembled molecule Me-4PACz at the equilibrium heterojunction interface in nickel oxide (Control), calculated using classical molecular dynamics simulations, are attached. Figure 4 This result also demonstrates that self-assembled molecules readily aggregate and stack longitudinally on the nickel oxide surface. The coverage images of other self-assembled molecules on the nickel oxide (001) surface in the comparison group of devices, calculated using classical molecular dynamics (MD) simulations, are attached. Figure 5 (Control) The control group devices exhibited localized protrusions and a significant portion of exposed nickel oxide surface. Based on the above analysis, a schematic diagram of the distribution of Me-4PACz self-assembled molecules on the substrate is attached. Figure 6 The above tests show that self-assembled molecules are prone to self-aggregation and longitudinal stacking on the substrate, which leads to problems such as uneven distribution and incomplete coverage of self-assembled molecules on the substrate surface.

[0051] After step 4 of the preparation process, samples were taken for in-situ PL testing during the perovskite spin-coating process. The results are attached. Figure 7 The perovskite films in the control group showed slower nucleation and growth rates during spin coating, resulting in weaker PL strength in the final grains. X-ray photoelectron spectroscopy (XPS) of F 1s and Pb 4f at the buried interface of the perovskite films was performed on samples; the results are attached. Figure 9 (Control), Appendix Figure 10 (Control). Samples were taken for PL mapping tests on the buried interface of the perovskite thin film; the results are attached. Figure 11 The PL intensity of the control group films was weaker and more unevenly distributed. Scanning electron microscopy (SEM) tests were performed on samples at the buried interface of the perovskite films; the results are attached. Figure 13 The control group's films exhibited obvious pores and cracks at the buried interface. Destructive testing was performed on samples placed in an environment of 85℃ and 40% relative humidity, and X-ray diffraction was used to test their stability. The results are shown in the attached figure. Figure 15 The control group degraded and decomposed into lead iodide over time. ATR-FTIR tests were performed on perovskite powder, and the results are attached. Figure 17 and 18 (All tests above were conducted based on sampling at the end of step 4.) The control group device C was prepared through all the above steps, and the performance test results under a solar intensity simulator are shown in the appendix. Figure 21 Characteristic battery performance parameters: Short-circuit current 25.50 mA / cm 2 The open-circuit voltage is 1145 mV, the fill factor is 80.52%, and the power conversion efficiency is 23.51%. Stability testing: In the unpackaged control group, device C decayed to 66% of its initial efficiency after 672 hours of continuous heating at 65℃ in a N2 atmosphere, as shown in the attached figure. Figure 28 In the comparison group, device C, without encapsulation or protection, decayed to 67.8% of its initial efficiency after 500 hours of maximum power point tracking under LED illumination of a single sunlight intensity. (See attached figure.) Figure 29 .

[0052] The above tests demonstrate that there are significant problems between the bottom interface and the perovskite active layer of device C in the control group, including interfacial side reactions, ion migration, non-radiative recombination, and susceptibility to damage by external polar molecules. These problems restrict the energy conversion efficiency and stability of the device under operating conditions.

[0053] Example 2: The device prepared in this embodiment is the experimental group, named device D. The structural schematic diagram of experimental group device D is attached. Figure 1 As shown in (d), it is composed of ITO glass (1), hole transport layer (9), interface modification layer (8), perovskite light-absorbing layer (3), interface passivation layer (4), electron transport layer (5), hole blocking layer (6) and metal electrode (7), and its preparation steps are as follows: 1. Clean the conductive and light-transmitting substrate (1.5 cm × 1.5 cm in size and 0.7 mm in thickness) in sequence with glass cleaner, deionized water, acetone, isopropanol and ethanol, then soak it in ethanol, blow it dry with nitrogen, and treat it with ultraviolet ozone before use. 2. Coat the substrate surface with 50 μL of nickel oxide (NiO) at a concentration of 10 mg / mL. x , x The nickel oxide hole transport layer with a thickness of 4 nm was prepared by heating the dispersion in 1-2) on a hot stage at 100°C for 10 minutes in an air environment with a relative humidity of 10-40% on an air environment. 3. In an anhydrous, oxygen-free, and dust-free environment, this can generally be achieved using a glove box device, by coating NiO with 50 μL of a 0.25 mg / mL perfluoro(2-methyl-3-oxahexanoic acid solution (ethanol as solvent)). x The film was then heated on a hot plate at 100°C for 10 minutes; then 50 μL of a solution of other self-assembled molecules [4-(3,6-dimethyl-9H-carbazole-9-yl)butyl]phosphonic acid (ethanol solvent) with a concentration of 0.5 mg / mL was coated onto the interface obtained above to prepare an interface modification layer with a thickness of 1.3 nm. 4. In an anhydrous, oxygen-free, and dust-free environment, this can generally be achieved using a glove box device. 50 μL of perovskite precursor solution (obtained by dissolving CsI, FAI, MAI, PbI2, and MACl in a mixed solvent at a molar ratio of 0.075:1.275:0.1497:1.65:0.186 and stirring for 5 h in a DMF and DMSO solution with a volume ratio of 4:1, and the precursor solution chemical composition is CsI…) is… 0.05 FA 0.85 MA 0.1 PbI3), spin-coated at 1000 rpm for 10 s, followed by 5000 rpm for 30 s. Using the anti-solvent method, 120 μL of chlorobenzene was injected with a pipette or dropper at the 20th s of the 5000 rpm process. After removing the substrate, it was heated on a hot stage at 100℃ for 30 minutes to achieve a thickness of 790 nm. 5. An interface passivation layer was prepared on the surface of the perovskite light-absorbing layer. Specifically, during the 5th second of the substrate rotation at 4000 rpm for 30 seconds, 25 μL of PEAI interface passivation layer solution (concentration of 2 mg / mL, solvent of isopropanol) was pipetted onto the center of the substrate by rotating and dropping. The drop height was limited to 0.5 cm. After the drop was completed, the substrate was heated on a hot stage at 100℃ for 10 min, and the thickness was 1.5 nm. 6. High vacuum 10 -4 C is prepared by vacuum deposition in environments below Pa. 60 An electron transport layer with a thickness of 25 nm; 7. High vacuum 10 -4 A hole-blocking layer with a thickness of 6.5 nm was prepared by vacuum deposition in an environment below Pa. 8. High vacuum 10 -4 Ag metal electrode layers are deposited in an environment below Pa, with the deposition environment maintained below 50°C, and the deposition thickness is 150 nm.

[0054] This embodiment presents a perovskite solar cell based on a perfluorinated self-assembled molecule as the interface modification layer. After step 3, coating the perfluorinated self-assembled molecule, the sample was taken for X-ray photoelectron spectroscopy (XPS) analysis, and the results are attached. Figure 2 (Target group) Fluorine was detected on the surface of the hole transport layer. After step 3 of preparation, samples were taken for X-ray diffraction analysis; the results are attached. Figure 3 (Target group), other self-assembled molecules show no longitudinal stacking diffraction peaks. The top view (top image) and side view (bottom image) of the equilibrium heterojunction interface structure of the self-assembled molecule Me-4PACz on the nickel oxide surface after PFA molecules preferentially form a confined interface (Target) are shown in the attached figures, calculated using classical molecular dynamics simulations. Figure 4 This result further demonstrates that the discrete confinement formed by perfluorinated self-assembled molecules can disperse other self-assembled molecules and inhibit their longitudinal stacking on the nickel oxide surface. The image showing the coverage of other self-assembled molecules on the nickel oxide (001) surface adsorbed with perfluorinated self-assembled molecules in the experimental group of devices, calculated using classical molecular dynamics (MD) simulations, is attached. Figure 5 (Target) In the experimental group, other self-assembled molecules were distributed relatively evenly and achieved almost complete coverage. Based on the above analysis, a schematic diagram of the distribution of the self-assembled molecule Me-4PACz on the substrate is attached. Figure 6 By comparing the above test results with the test results prepared in step 3 of Comparative Example 2, it can be seen that perfluorinated self-assembled molecules can effectively suppress the longitudinal stacking of self-assembled molecules and enable them to cover the substrate surface more uniformly and completely.

[0055] After step 4 of the preparation process, samples were taken for in-situ PL testing during the perovskite spin-coating process. The results are attached. Figure 8 The experimental group of perovskite films exhibited slower nucleation and growth rates during spin coating, and the resulting grains showed stronger PL intensity compared to the control group. X-ray photoelectron spectroscopy (XPS) of F 1s and Pb 4f at the buried interface of the perovskite films was performed on samples; the results are attached. Figure 9 (Target) and attached Figure 10 (Target), F 1s in the experimental group (and) Figure 2 The shifts in both the F1s target and Pb 4f peaks indicate an interaction between the perfluorinated self-assembled molecules and the buried interface of the perovskite active layer. PL mapping tests were performed on samples to analyze the buried interface of the perovskite film; the results are attached. Figure 12The experimental group of films exhibited stronger and more uniform PL strength than the control group. Scanning electron microscopy (SEM) tests were performed on samples at the buried interface of the perovskite films; the results are attached. Figure 14 The experimental group of perovskite films exhibited a more uniform and dense buried interface, along with increased grain size, indicating better crystallinity. Destructive testing was performed on samples placed in an environment of 85℃ and 40% relative humidity. X-ray diffraction was used to assess their stability, and the results are shown in the attached figure. Figure 16 The degradation phenomenon in the experimental group was significantly inhibited over time. ATR-FTIR tests were performed on perovskite powder and a mixture of PFA and perovskite (PFA+PVSK), and the results are shown in the attached figure. Figure 17 and 18 The peaks for both NH stretching vibration and CF stretching vibration shifted. (All tests were conducted after sampling at the end of step 4.) The experimental device D was prepared through all the above steps, and the performance test results under a solar intensity simulator are shown in the attached figure. Figure 22 Characteristic battery performance parameters: Short-circuit current 26.22 mA / cm 2 The open-circuit voltage is 1182 mV, the fill factor is 86.61%, and the power conversion efficiency is 26.84%. Stability testing: Device D in the unpackaged experimental group maintained 95.2% of its initial efficiency after being continuously heated at 65℃ in a N2 atmosphere for 1000 hours, as shown in the attached figure. Figure 28 (Target Group); Device D in the unpackaged experimental group maintained 94.6% of its initial efficiency after 800 hours of maximum power point tracking under illumination from a single LED light source with sunlight intensity, as shown in the attached figure. Figure 29 It is significantly superior to the devices in the comparison group.

[0056] In summary, the results show that the interface modification layer formed by using perfluorinated self-assembled molecules can improve the crystallinity of perovskite films, while effectively suppressing harmful reactions at the buried interface, passivating interface defects, reducing non-radiative recombination at the interface, and inhibiting ion migration, thereby significantly improving the energy conversion efficiency and stability of perovskite solar cells.

[0057] Example 3: The device prepared in this embodiment is the experimental group, named device E. The structural schematic diagram of experimental group device E is attached. Figure 1 As shown in (d), it is composed of ITO glass (1), hole transport layer (9), interface modification layer (8), perovskite light-absorbing layer (3), interface passivation layer (4), electron transport layer (5), hole blocking layer (6) and metal electrode (7), and its preparation steps are as follows: 1. Clean the conductive and light-transmitting substrate (1.5 cm × 1.5 cm in size and 0.7 mm in thickness) in sequence with glass cleaner, deionized water, acetone, isopropanol and ethanol, then soak it in ethanol, blow it dry with nitrogen, and treat it with ultraviolet ozone before use. 2. Coat the substrate surface with 50 μL of nickel oxide (NiO) at a concentration of 10 mg / mL. x , x The nickel oxide hole transport layer with a thickness of 4 nm was prepared by heating the dispersion in 1-2) on a hot stage at 100°C for 10 minutes in an air environment with a relative humidity of 10-40% on an air environment. 3. In an anhydrous, oxygen-free, and dust-free environment, this can generally be achieved using a glove box device, by coating NiO with 50 μL of a 0.125 mg / mL perfluoro(2-methyl-3-oxahexanoic acid) solution (ethanol as solvent). x The film was then heated on a hot plate at 100°C for 10 minutes; then 50 μL of a solution of other self-assembled molecules [4-(3,6-dimethyl-9H-carbazole-9-yl)butyl]phosphonic acid (ethanol solvent) with a concentration of 0.5 mg / mL was coated onto the interface obtained above to prepare an interface modification layer with a thickness of 1.3 nm. 4. In an anhydrous, oxygen-free, and dust-free environment, this can generally be achieved using a glove box device. 50 μL of perovskite precursor solution (obtained by dissolving CsI, FAI, MAI, PbI2, and MACl in a mixed solvent at a molar ratio of 0.075:1.275:0.1497:1.65:0.186 and stirring for 5 h in a DMF and DMSO solution with a volume ratio of 4:1, and the precursor solution chemical composition is CsI…) is… 0.05 FA 0.85 MA 0.1 PbI3), spin-coated at 1000 rpm for 10 s, followed by 5000 rpm for 30 s. Using the anti-solvent method, 120 μL of chlorobenzene was injected with a pipette or dropper at the 20th s of the 5000 rpm process. After removing the substrate, it was heated on a hot stage at 100℃ for 30 minutes to achieve a thickness of 790 nm. 5. Prepare a PEAI interface passivation layer on the surface of the perovskite light-absorbing layer. Specifically, during the 5th second of the substrate rotation at 4000 rpm for 30 s, use a pipette to pick up 25 μL of the interface passivation layer solution (concentration of 2 mg / mL, solvent of isopropanol) and drop it onto the center of the substrate in a rotating drop manner. The drop height is limited to 0.5 cm. After the drop is completed, heat it on a hot stage at 100℃ for 10 min. The thickness is 1.5 nm. 6. High vacuum 10 -4 C is prepared by vacuum deposition in environments below Pa.60 An electron transport layer with a thickness of 25 nm; 7. High vacuum 10 -4 A hole-blocking layer with a thickness of 6.5 nm was prepared by vacuum deposition in an environment below Pa. 8. High vacuum 10 -4 Ag metal electrode layers are deposited in an environment below Pa, with the deposition environment maintained below 50°C, and the deposition thickness is 150 nm.

[0058] The performance of the fabricated perovskite solar cells was tested using a solar intensity simulator, and the results are shown in the attached figure. Figure 23 The current is 26.19 mA / cm. 2 The opening voltage is 1164 mV, the fill factor is 85.40%, and the energy conversion efficiency is 26.03%.

[0059] Example 4: The device prepared in this embodiment is the experimental group, named device F. A schematic diagram of the structure of experimental group device F is attached. Figure 1 As shown in (d), it is composed of ITO glass (1), hole transport layer (9), interface modification layer (8), perovskite light-absorbing layer (3), interface passivation layer (4), electron transport layer (5), hole blocking layer (6) and metal electrode (7), and its preparation steps are as follows: 1. Clean the conductive and light-transmitting substrate (1.5 cm × 1.5 cm in size and 0.7 mm in thickness) in sequence with glass cleaner, deionized water, acetone, isopropanol and ethanol, then soak it in ethanol, blow it dry with nitrogen, and treat it with ultraviolet ozone before use. 2. Coat the substrate surface with 50 μL of nickel oxide (NiO) at a concentration of 10 mg / mL. x , x The nickel oxide hole transport layer with a thickness of 4 nm was prepared by heating the dispersion in 1-2) on a hot stage at 100°C for 10 minutes in an air environment with a relative humidity of 10-40% on an air environment. 3. In an anhydrous, oxygen-free, and dust-free environment, this can generally be achieved using a glove box device, by coating NiO with 50 μL of a 0.5 mg / mL perfluoro(2-methyl-3-oxahexanoic acid solution (ethanol as solvent)). x The film was then heated on a hot plate at 100°C for 10 minutes; then 50 μL of a solution of other self-assembled molecules [4-(3,6-dimethyl-9H-carbazole-9-yl)butyl]phosphonic acid (ethanol solvent) with a concentration of 0.5 mg / mL was coated onto the interface obtained above to prepare an interface modification layer with a thickness of 1.3 nm. 4. In an anhydrous, oxygen-free, and dust-free environment, this can generally be achieved using a glove box device. 50 μL of perovskite precursor solution (obtained by dissolving CsI, FAI, MAI, PbI2, and MACl in a mixed solvent at a molar ratio of 0.075:1.275:0.1497:1.65:0.186 and stirring for 5 h in a DMF and DMSO solution with a volume ratio of 4:1, and the precursor solution chemical composition is CsI…) is… 0.05 FA 0.85 MA 0.1 PbI3), spin-coated at 1000 rpm for 10 s, followed by 5000 rpm for 30 s. Using the anti-solvent method, 120 μL of chlorobenzene was injected with a pipette or dropper at the 20th s of the 5000 rpm process. After removing the substrate, it was heated on a hot stage at 100℃ for 30 minutes to achieve a thickness of 790 nm. 5. Prepare a PEAI interface passivation layer on the surface of the perovskite light-absorbing layer. Specifically, during the 5th second of the substrate rotation at 4000 rpm for 30 s, use a pipette to pick up 25 μL of the interface passivation layer solution (concentration of 2 mg / mL, solvent of isopropanol) and drop it onto the center of the substrate in a rotating drop manner. The drop height is limited to 0.5 cm. After the drop is completed, heat it on a hot stage at 100℃ for 10 min. The thickness is 1.5 nm. 6. High vacuum 10 -4 C is prepared by vacuum deposition in environments below Pa. 60 An electron transport layer with a thickness of 25 nm; 7. High vacuum 10 -4 A hole-blocking layer with a thickness of 6.5 nm was prepared by vacuum deposition in an environment below Pa. 8. High vacuum 10 -4 Ag metal electrode layers are deposited in an environment below Pa, with the deposition environment maintained below 50°C, and the deposition thickness is 150 nm.

[0060] The performance of the fabricated perovskite solar cells was tested using a solar intensity simulator, and the results are shown in the attached figure. Figure 24 The current is 26.11 mA / cm. 2 The opening voltage is 1179 mV, the fill factor is 85.61%, and the energy conversion efficiency is 26.35%.

[0061] Example 5: The device prepared in this embodiment is the experimental group, named device G. The structural schematic diagram of experimental group device G is attached. Figure 1As shown in (d), it is composed of ITO glass (1), hole transport layer (9), interface modification layer (8), perovskite light-absorbing layer (3), interface passivation layer (4), electron transport layer (5), hole blocking layer (6) and metal electrode (7), and its preparation steps are as follows: 1. Clean the conductive and light-transmitting substrate (1.5 cm × 1.5 cm in size and 0.7 mm in thickness) in sequence with glass cleaner, deionized water, acetone, isopropanol and ethanol, then soak it in ethanol, blow it dry with nitrogen, and treat it with ultraviolet ozone before use. 2. Coat the substrate surface with 50 μL of nickel oxide (NiO) at a concentration of 10 mg / mL. x , x The nickel oxide hole transport layer with a thickness of 4 nm was prepared by heating the dispersion in 1-2) on a hot stage at 100°C for 10 minutes in an air environment with a relative humidity of 10-40% on an air environment. 3. In an anhydrous, oxygen-free, and dust-free environment, this can generally be achieved using a glove box device, by coating NiO with 50 μL of a 0.25 mg / mL perfluoro-2,5-dimethyl-3,6-dioxane-heptanoic acid solution (ethanol as solvent). x The film was then heated on a hot plate at 80-120℃ for 10 minutes; then 50 μL of a solution of other self-assembled molecules [4-(3,6-dimethyl-9H-carbazole-9-yl)butyl]phosphonic acid (ethanol solvent) with a concentration of 0.5 mg / mL was coated onto the interface obtained above to prepare an interface modification layer with a thickness of 1.3 nm. 4. In an anhydrous, oxygen-free, and dust-free environment, this can generally be achieved using a glove box device. 50 μL of perovskite precursor solution (obtained by dissolving CsI, FAI, MAI, PbI2, and MACl in a mixed solvent at a molar ratio of 0.075:1.275:0.1497:1.65:0.186 and stirring for 5 h in a DMF and DMSO solution with a volume ratio of 4:1, and the precursor solution chemical composition is CsI…) is… 0.05 FA 0.85 MA 0.1 PbI3), spin-coated at 1000 rpm for 10 s, followed by 5000 rpm for 30 s. Using the anti-solvent method, 120 μL of chlorobenzene was injected with a pipette or dropper at the 20th s of the 5000 rpm process. After removing the substrate, it was heated on a hot stage at 100 ℃ for 30 minutes, with a thickness of 790 nm. 5. An interface passivation layer was prepared on the surface of the perovskite light-absorbing layer. Specifically, during the 5th second of the substrate rotation at 4000 rpm for 30 seconds, 25 μL of PEAI interface passivation layer solution (concentration of 2 mg / mL, solvent of isopropanol) was pipetted onto the center of the substrate by rotating and dropping. The drop height was limited to 0.5 cm. After the drop was completed, the substrate was heated on a hot stage at 100℃ for 10 min, and the thickness was 1.5 nm. 6. High vacuum 10 -4 C is prepared by vacuum deposition in environments below Pa. 60 An electron transport layer with a thickness of 25 nm; 7. High vacuum 10 -4 A hole-blocking layer with a thickness of 6.5 nm was prepared by vacuum deposition in an environment below Pa. 8. High vacuum 10 -4 Ag metal electrode layers are deposited in an environment below Pa, with the deposition environment maintained below 50°C, and the deposition thickness is 150 nm.

[0062] The performance of the fabricated perovskite solar cells was tested using a solar intensity simulator, and the results are shown in the attached figure. Figure 25 The current is 25.76 mA / cm. 2 The opening voltage is 1163 mV, the fill factor is 84.88%, and the energy conversion efficiency is 25.43%.

[0063] Example 6: The device prepared in this embodiment is the experimental group, named device H. The structural schematic diagram of experimental group device H is attached. Figure 1 As shown in (d), it is composed of ITO glass (1), hole transport layer (9), interface modification layer (8), perovskite light-absorbing layer (3), interface passivation layer (4), electron transport layer (5), hole blocking layer (6) and metal electrode (7), and its preparation steps are as follows: 1. Clean the conductive and light-transmitting substrate (1.5 cm × 1.5 cm in size and 0.7 mm in thickness) in sequence with glass cleaner, deionized water, acetone, isopropanol and ethanol, then soak it in ethanol, blow it dry with nitrogen, and treat it with ultraviolet ozone before use. 2. Coat the substrate surface with 50 μL of nickel oxide (NiO) at a concentration of 10 mg / mL. x , x The nickel oxide hole transport layer with a thickness of 4 nm was prepared by heating the dispersion in 1-2) on a hot stage at 100°C for 10 minutes in an air environment with a relative humidity of 10-40% on an air environment. 3. In an anhydrous, oxygen-free, and dust-free environment, this can generally be achieved using a glove box device, by coating NiO with 50 μL of a 0.25 mg / mL perfluorooctylphosphonic acid solution (ethanol as solvent). x The film was then heated on a hot plate at 100°C for 10 minutes; then 50 μL of a solution of other self-assembled molecules [4-(3,6-dimethyl-9H-carbazole-9-yl)butyl]phosphonic acid (ethanol solvent) with a concentration of 0.5 mg / mL was coated onto the interface obtained above to prepare an interface modification layer with a thickness of 1.3 nm. 4. In an anhydrous, oxygen-free, and dust-free environment, this can generally be achieved using a glove box device. 50 μL of perovskite precursor solution (obtained by dissolving CsI, FAI, MAI, PbI2, and MACl in a mixed solvent at a molar ratio of 0.075:1.275:0.1497:1.65:0.186 and stirring for 5 h in a DMF and DMSO solution with a volume ratio of 4:1, and the precursor solution chemical composition is CsI…) is… 0.05 FA 0.85 MA 0.1 PbI3), spin-coated at 1000 rpm for 10 s, followed by 5000 rpm for 30 s. Using the anti-solvent method, 120 μL of chlorobenzene was injected with a pipette or dropper at the 20th s of the 5000 rpm process. After removing the substrate, it was heated on a hot stage at 100 ℃ for 30 minutes, with a thickness of 790 nm. 5. Prepare a PEAI interface passivation layer on the surface of the perovskite light-absorbing layer. Specifically, during the 5th second of the substrate rotation at 4000 rpm for 30 seconds, use a pipette to pick up 25 μL of the interface passivation layer solution (concentration of 2 mg / mL, solvent of isopropanol) and drop it onto the center of the substrate in a rotating drop manner. The drop height is limited to 0.5 cm. After the drop is completed, heat it on a hot stage at 100℃ for 10 min. The thickness is 1.5 nm. 6. High vacuum 10 -4 C is prepared by vacuum deposition in environments below Pa. 60 An electron transport layer with a thickness of 25 nm; 7. High vacuum 10 -4 A hole-blocking layer with a thickness of 6.5 nm was prepared by vacuum deposition in an environment below Pa. 8. High vacuum 10 -4 Ag metal electrode layers are deposited in an environment below Pa, with the deposition environment maintained below 50°C, and the deposition thickness is 150 nm.

[0064] The performance of the fabricated perovskite solar cells was tested using a solar intensity simulator, and the results are shown in the attached figure. Figure 26 The current is 25.80 mA / cm.2 The opening voltage is 1156 mV, the fill factor is 84.29%, and the energy conversion efficiency is 25.14%.

[0065] Example 7: The device prepared in this embodiment is the experimental group, named device I. The structural schematic diagram of experimental group device I is attached. Figure 1 As shown in (d), it is composed of ITO glass (1), hole transport layer (9), interface modification layer (8), perovskite light-absorbing layer (3), interface passivation layer (4), electron transport layer (5), hole blocking layer (6) and metal electrode (7), and its preparation steps are as follows: 1. Clean the conductive and light-transmitting substrate (1.5 cm × 1.5 cm in size and 0.7 mm in thickness) in sequence with glass cleaner, deionized water, acetone, isopropanol and ethanol, then soak it in ethanol, blow it dry with nitrogen, and treat it with ultraviolet ozone before use. 2. Coat the substrate surface with 50 μL of nickel oxide (NiO) at a concentration of 10 mg / mL. x , x The nickel oxide hole transport layer with a thickness of 4 nm was prepared by heating the dispersion in 1-2) on a hot stage at 100°C for 10 minutes in an air environment with a relative humidity of 10-40% on an air environment. 3. In an anhydrous, oxygen-free, and dust-free environment, this can generally be achieved using a glove box device, by coating NiO with 50 μL of a 0.25 mg / mL perfluoro(2-methyl-3-oxahexanoic acid solution (ethanol as solvent)). x The film was then heated on a hot plate at 100°C for 10 minutes; then 50 μL of a solution of other self-assembled molecules [4-(3,6-dimethyl-9H-carbazole-9-yl)butyl]phosphonic acid (ethanol solvent) with a concentration of 0.5 mg / mL was coated onto the interface obtained above to prepare an interface modification layer with a thickness of 1.3 nm. 4. In an anhydrous, oxygen-free, and dust-free environment, this can generally be achieved using a glove box device. 50 μL of perovskite precursor solution (obtained by dissolving CsI, FAI, MAI, PbI2, and MACl in a mixed solvent at a molar ratio of 0.075:1.275:0.1497:1.65:0.186 and stirring for 5 h in a DMF and DMSO solution with a volume ratio of 4:1, and the precursor solution chemical composition is CsI…) is… 0.05 FA 0.85 MA 0.1PbI3), spin-coated at 1000 rpm for 10 s, followed by 5000 rpm for 30 s. Using the anti-solvent method, 120 μL of chlorobenzene was injected with a pipette or dropper at the 20th s of the 5000 rpm process. After removing the substrate, it was heated on a hot stage at 100℃ for 30 minutes to achieve a thickness of 790 nm. 5. An interface passivation layer was prepared on the surface of the perovskite light-absorbing layer. Specifically, during the 5th second of the substrate rotation at 4000 rpm for 30 seconds, 25 μL of PEAI interface passivation layer solution (concentration of 2 mg / mL, solvent of isopropanol) was pipetted onto the center of the substrate by rotating and dropping. The drop height was limited to 0.5 cm. After the drop was completed, the substrate was heated on a hot stage at 100℃ for 10 min, and the thickness was 1.5 nm. 6. High vacuum 10 -4 C is prepared by vacuum deposition in environments below Pa. 60 An electron transport layer with a thickness of 25 nm; 7. High vacuum 10 -4 Tin oxide (SnO) is prepared by atomic layer deposition in environments below Pa. x , x A hole-blocking layer with a thickness of 25 nm (between 1.8 and 2.0). 8. High vacuum 10 -4 Ag metal electrode layers are deposited in an environment below Pa, with the deposition environment maintained below 50°C, and the deposition thickness is 150 nm.

[0066] The performance of the fabricated perovskite solar cells was tested using a solar intensity simulator, and the results are shown in the attached figure. Figure 27 The current is 26.21 mA / cm. 2 The opening voltage is 1178 mV, the fill factor is 86.20%, and the energy conversion efficiency is 26.61%.

[0067] Matters not covered in this invention are common knowledge.

Claims

1. A perovskite solar cell based on a perfluorinated self-assembled molecule as an interface modification layer, characterized in that, The battery has one of the following two structures: Structure 1 consists of, from bottom to top, a conductive and transparent substrate, a hole transport layer, an interface modification layer, a perovskite light-absorbing layer, an interface passivation layer, an electron transport layer, a hole blocking layer, and a metal electrode layer. Alternatively, structure two consists of, from bottom to top, a conductive and transparent substrate, an interface modification layer, a perovskite light-absorbing layer, an interface passivation layer, an electron transport layer, a hole blocking layer, and a metal electrode layer. The interface modification layer is composed of perfluorinated self-assembled molecules and other self-assembled molecules, which are arranged alternately on the substrate in a ratio of 1:100 to 1:1.5, and the total thickness of the film is 1-4 nm. The perfluorinated self-assembled molecule is selected from at least one of perfluoro(2-methyl-3-oxa)hexanoic acid, perfluoro-2,5-dimethyl-3,6-dioxaheptanic acid, perfluorooctane carboxylic acid, and perfluorooctylphosphonic acid. The other self-assembled molecules are substance A or substance B; Substance A is one or more of the following: [2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl]phosphonic acid, [2-(3,6-dimethyl-9H-carbazole-9-yl)ethyl]phosphonic acid, [4-(3,6-dimethyl-9H-carbazole-9-yl)butyl]phosphonic acid, [4-(3,6-diphenyl-9H-carbazole-9-yl)butyl]phosphonic acid, and [4-(7H-dibenzo[c,g]carbazole-7-yl)butyl]phosphonic acid; Substance B is one or more of the polymers [2-(3,6-poly-9H-carbazole-9-yl)ethyl]phosphonic acid and [4-(3,6-poly-9H-carbazole-9-yl)butyl]phosphonic acid, with a molecular weight between 1,000 and 100,000.

2. The perovskite solar cell based on perfluorinated self-assembled molecules as an interface modification layer as described in claim 1, characterized in that, In the interface modification layer, perfluorinated self-assembled molecules form the framework of the compartments, while other self-assembled molecules occupy the uncovered areas within the compartments, together constituting a complete interface modification layer. The coverage of perfluorinated self-assembled molecules on the substrate is 5-39%, the spacing is 1.0-100 nm, and the thickness is 0.5-2.0 nm. Ultimately, the interface modification layer composed of perfluorinated self-assembled molecules and other self-assembled molecules can achieve a coverage of 90-100% on the substrate surface.

3. The perovskite solar cell based on a perfluorinated self-assembled molecule as an interface modification layer as described in claim 1, characterized in that, The conductive and light-transmitting substrate is made of rigid glass, flexible substrate polyethylene terephthalate, polyethylene naphthalate, or polyimide. The light-transmitting and conductive layer on top is made of fluorine-doped tin oxide with a thickness of 300-1000 nm; or indium-doped tin oxide with a thickness of 50-150 nm. The hole transport layer is made of nickel oxide or polytriarylamine, and the film thickness is 2-30 nm. The perovskite light-absorbing layer is (Cs) x MA y FA 1-x-y )Pb(I a Br 1-a )3, of which x The φ is between 0.02 and 0.20, y is between 0.02 and 0.20, a is between 0.60 and 1.00, and the film thickness is 200-1000 nm; The interface passivation layer is one or two of 1,3-diaminopropane dihydroiodate, n-octylammonium iodide, piperazine dihydroiodate, phenylethylammonium iodate, and 3-methylthio-1-propylamine hydroiodate, with a thickness of 1-20 nm. The electron transport layer is [6,6]-phenyl-C61-butyrate isomethyl ester, C 60 C 70 One of them has a film thickness of 10-40 nm; The hole-blocking layer is one of 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline and tin oxide, and the film thickness is 3-30 nm. The metal electrode layer comprises one or more of gold, silver, copper, and aluminum, with a thickness of 50-200 nm.

4. The perovskite solar cell based on perfluorinated self-assembled molecules as an interface modification layer as described in claim 1, characterized in that, The interface modification layer improves the contact between the hole transport layer or transparent conductive substrate and the perovskite layer; the perfluorinated self-assembled molecules, through their own electrostatic repulsion and the discrete confined structure they form, suppress the longitudinal stacking of other self-assembled molecules, making them more uniform and complete in covering the substrate.

5. The method for preparing a perovskite solar cell based on a perfluorinated self-assembled molecule as an interface modification layer as described in claim 1, characterized in that, Use one of the following two methods: The preparation of Structure 1 includes the following steps: Step 1: Clean the conductive and transparent substrate in sequence with glass cleaner, deionized water, acetone, isopropanol and ethanol, then soak it in ethanol, blow it dry with nitrogen, and treat it with ultraviolet ozone before use. Step 2: Coat the substrate surface with a hole transport layer dispersion at a concentration of 5-20 mg / mL, and then heat it on a hot stage at 100-120℃ for 5-20 minutes in an air environment with a relative humidity of 10-40% to obtain the hole transport layer. The solvent for the hole transport layer dispersion is one or more of water, methanol, ethanol, isopropanol, and propanol. Coat each 2.0 to 2.5 square centimeter substrate with 20 to 100 microliters of nickel oxide dispersion; Step 3: In an anhydrous, oxygen-free, and dust-free environment, a perfluorinated self-assembled molecule solution with a concentration of 0.1-1.0 mg / mL is coated onto the hole transport layer, and then heated on a hot stage at 80-120℃ for 5-20 minutes; then, other self-assembled molecule solutions with a concentration of 0.2-2.0 mg / mL are coated onto the interface obtained above to prepare an interface modification layer; The solvent for the solutions of the perfluorinated self-assembled molecules and other self-assembled molecules is the same, namely one or more of water, methanol, ethanol, isopropanol, and propanol; Step 4: In an environment free of water, oxygen, and dust, coat the perovskite precursor solution onto the interface modification layer obtained above, and prepare a perovskite film using the anti-solvent method or vacuum flash evaporation method. The film thickness is 200-1000 nm. After removing the substrate, heat it on a hot stage at 80-120℃ for 20-40 minutes to prepare the perovskite light-absorbing layer. Add 2 to 60 microliters of perovskite precursor solution to every 2.0 to 2.5 square centimeters of substrate; Step 5: In an anhydrous, oxygen-free, and dust-free environment, coat the perovskite light-absorbing layer obtained above with an interface passivation layer solution of 0.1-1.0 mg / mL, and then heat it on a hot stage at 80-120℃ for 5-10 min to prepare an interface passivation layer with a thickness of 1-20 nm. Add 2-60 μL of interface passivation layer solution to every 2.0-2.5 square centimeters of substrate; The interface passivation layer is made of one or two of 1,3-diaminopropane dihydroiodate, n-octylammonium iodide, piperazine dihydroiodate, phenylethylammonium iodate, and 3-methylthio-1-propylamine hydroiodate, and the solvent is one or more of water, methanol, ethanol, isopropanol, and propanol, with a thickness of 1-20 nm. Step Six: Spin-coating an electron transport layer or a high-vacuum 10-layer electrode onto the interface passivation layer. -4 Electron transport layers with a thickness of 10-40 nm are prepared by vacuum deposition in environments below Pa. Step 7: Prepare a hole-blocking layer on the electron transport layer using spin coating or atomic layer deposition, or in a high vacuum of 10... -4 Hole blocking layers with a thickness of 5-30 nm are prepared by vacuum evaporation deposition in environments below Pa. Step 8: High Vacuum 10 -4 The metal electrode layer is deposited in an environment below Pa with a deposition thickness of 50-200 nm. The coating process includes spin coating, blade coating, and slot coating. Alternatively, the preparation of structure two includes the following steps: The other steps are the same as in Method 1, except that there is no step 2. That is, only steps 1, 3, 4, 5, 6, 7 and 8 from Method 1 are used in sequence. The difference in step 3 is that a perfluorinated self-assembled molecule solution with a concentration of 0.1-1.0 mg / mL is directly coated onto a conductive and transparent substrate.

6. The method for preparing a perovskite solar cell based on a perfluorinated self-assembled molecule as an interface modification layer as described in claim 5, characterized in that, The perovskite precursor solution is prepared according to the composition of the perovskite (Cs). x MA y FA 1-x-y )Pb(I a Br 1-a )3 configuration, in which, x The concentrations are between 0.02 and 0.20, y is between 0.02 and 0.20, a is between 0.60 and 1.00, and additional additives methylamine hydrochloride and excess lead iodide are added; wherein the amount of methylamine hydrochloride is 5%-35% of the molar concentration of perovskite, and the amount of lead iodide is 1%-10% of the molar concentration of perovskite.

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