A perovskite solar cell based on a perfluorinated self-assembled molecule as an interface modification layer and a preparation method thereof

Abstract

The application discloses a perovskite solar cell based on a perfluoro self-assembled molecule as an interface modification layer and a preparation method thereof. The perovskite solar cell comprises, from bottom to top, a conductive and light-transmitting 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. The interface modification layer is a complete layer formed by perfluoro self-assembled molecules and other self-assembled molecules, and the perfluoro self-assembled molecules are selected from at least one of perfluoro (2-methyl-3-oxa) hexanoic acid, perfluoro-2, 5-dimethyl-3, 6-dioxane heptanoic acid, perfluoro octanoic acid and perfluoro octyl phosphonic acid. The perfluoro self-assembled molecules can inhibit the longitudinal accumulation of other self-assembled molecules, so that the perfluoro self-assembled molecules can more uniformly and completely cover the substrate to inhibit harmful reactions of a buried 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] The present application relates to the technical field of perovskite solar cells, and particularly relates to a perovskite solar cell based on a perfluoro self-assembled molecule as an interface modification layer and a preparation method thereof. BACKGROUND

[0002] Perovskite solar cells have high light absorption coefficient, direct band gap energy band structure, long carrier lifetime, adjustable band gap width and other excellent optoelectronic properties, and have the advantages of simple preparation process and low cost, and have become one of the leading devices in the third generation of solar cells. At present, the highest energy conversion efficiency of single-junction perovskite cells has exceeded 27%, however, compared with crystalline silicon cells, gallium arsenide cells, copper indium gallium selenide cells, etc., the commercial application of perovskite photovoltaic devices is inhibited due to their stability problems.

[0003] In perovskite solar cells, there are often interface defects, energy level mismatch and chemical instability between the active layer and the conductive light-transmitting substrate (the substrate uses rigid glass or flexible conductive substrate polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyimide (PI), and the upper conductive layer is fluorine-doped tin oxide (FTO) or indium-doped tin oxide (ITO)) or the bottom hole transport material (such as NiO x , PTAA, PEDOT:PSS, etc.), which seriously restricts the device efficiency and long-term operation stability, and has become one of the core challenges in the industrialization process. At present, using self-assembled molecules for interface modification is considered to be an effective solution, which can improve the photoelectric conversion efficiency of the device to more than 25%. Self-assembled molecules not only can regulate the interface energy level matching, but also can effectively inhibit the adverse side reactions at the perovskite bottom interface. However, self-assembled molecules are prone to self-aggregation on the substrate surface, resulting in uneven interface contact, vertical stacking, and even dynamic response failure, which has become an important bottleneck restricting the further improvement of device efficiency and stability. Therefore, developing efficient interface modification for the buried bottom interface between the perovskite active layer and the conductive light-transmitting substrate or the hole transport layer has become a key technology to improve device performance and inhibit open-circuit voltage loss, and it is urgent to develop technical means for interface modification molecules with high coverage and interface regulation ability.

[0004] In order to solve the above problems, the current device is prepared by coating only self-assembled molecules under the perovskite light-absorbing layer or by a blending strategy of self-assembled molecules and other molecular materials to form a self-assembled molecule layer. The energy level regulation, defect passivation and interface protection of the self-assembled molecules are utilized, or the blending strategy of self-assembled molecules and other molecular materials can improve the incomplete coverage of the self-assembled molecules on the substrate to achieve the effects of optimizing the energy level arrangement, inhibiting the interface side reaction and reducing the interface non-radiative recombination. However, the pure self-assembled molecule strategy has the following problems: self-aggregation and vertical stacking easily occur on the substrate surface, which leads to uneven interface contact and is not conducive to the formation of high-quality perovskite thin film; and the blending strategy has the following problems: the multiple molecules have chemical interaction in the solution, and the other molecular materials do not have stability for anchoring on the substrate; uncontrollability, since the self-assembled molecules and other molecular materials are preferentially mixed in the solution by the blending technology, the precipitation process on the substrate is uncontrollable, and the randomness of the uniformity of the self-assembled molecule coverage is caused. Therefore, the energy conversion efficiency realized by the prior art is still lower than 26%, and the interface is dynamically unstable and the device stability is poor. SUMMARY

[0005] The purpose of the present application is to provide a perovskite solar cell based on a perfluoro self-assembled molecule as an interface modification layer and a preparation method thereof. The perfluoro self-assembled molecule inhibits the vertical stacking of other self-assembled molecules and makes them more uniformly and completely cover the substrate, thereby inhibiting the harmful reaction of the buried bottom interface, passivating the interface defects and reducing the interface non-radiative recombination, and finally greatly improving the energy conversion efficiency and stability of the perovskite solar cell. In more detail, the perfluoro self-assembled molecule incompletely covers the substrate to form a discrete distribution structure, and other self-assembled molecules are confined in the structure to form a complete interface modification layer. The perfluoro self-assembled molecule inhibits the vertical stacking of self-assembled molecules by its own electrostatic repulsion and the discrete confinement structure formed thereby, and makes them more uniformly and completely cover the substrate. At the same time, the interface modification layer formed by this technical means strengthens the chemical interaction between the layer and the perovskite bottom interface, makes the interface structure more stable, and is conducive to regulating the crystallization growth process of the perovskite light-absorbing layer, and finally realizes higher photoelectric conversion efficiency and higher stability.

[0006] The technical scheme of the present application is as follows:

[0007] A perovskite solar cell based on a perfluoro self-assembled molecule as an interface modification layer has one of the following two structures:

[0008] Structure one, from bottom to top, is a conductive and light-transmitting 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;

[0009] Alternatively, structure two, from bottom to top, is conductive and light-transmitting substrate, interface modification layer, perovskite light-absorbing layer, interface passivation layer, electron transport layer, hole blocking layer and metal electrode layer;

[0010] The interface modification layer is composed of perfluoro self-assembled molecules and other self-assembled molecules, which are arranged alternately on the substrate, with a distribution ratio of 1:100-1:1, and a total film thickness of 1-4 nm;

[0011] The perfluoro self-assembled molecules are selected from at least one of perfluoro (2-methyl-3-oxa) hexanoic acid (PFA), perfluoro-2,5-dimethyl-3,6-dioxane heptanoic acid, perfluoro octanoic acid, and perfluoro octyl phosphonic acid;

[0012] The other self-assembled molecules are substance A or substance B;

[0013] The substance A is one or more of [2-(3,6-dimethoxy-9H-carbazol-9-yl) ethyl] phosphonic acid (MeO-2PACz), [2-(3,6-dimethyl-9H-carbazol-9-yl) ethyl] phosphonic acid (Me-2PACz), [4-(3,6-dimethyl-9H-carbazol-9-yl) butyl] phosphonic acid (Me-4PACz), [4-(3,6-diphenyl-9H-carbazol-9-yl) butyl] phosphonic acid (Ph-4PACz), [4-(7H-dibenzo[c,g] carbazol-7-yl) butyl] phosphonic acid (4PADCB);

[0014] The substance B is one or more of polymer-[2-(3,6-poly-9H-carbazol-9-yl) ethyl] phosphonic acid (poly-2PACz), polymer-[4-(3,6-poly-9H-carbazol-9-yl) butyl] phosphonic acid (poly-4PACz), with a polymer molecular weight of 1000-100000;

[0015] The substrate of the conductive and light-transmitting substrate is rigid glass, flexible substrate polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyimide (PI), and the upper light-transmitting conductive layer is fluorine-doped tin oxide (FTO, thickness of 300-1000 nm) or indium-doped tin oxide (ITO, thickness of 50-150 nm);

[0016] The material of the hole transport layer is nickel oxide (NiO x , x 1-2) or polytriazole (PTAA), with a film thickness of 2-30 nm;

[0017] The perovskite light-absorbing layer is composed of an organic metal halide layer, and the specific material is cesium methylamine formamidine lead iodine bromide (Csx MA y FA 1-x-y )Pb(I a Br 1-a )3, wherein x 0.02-0.20, y is between 0.02-0.20, a is between 0.60-1.00, and the film thickness is between 200-1000 nm, wherein the perovskite precursor solution is configured according to the components described above, and additional additives methylamine hydrochloride (molar ratio 5-35%) and excess lead iodide (molar ratio 0-10%) are added.

[0018] The interface passivation layer is one or more of 1,3-diaminopropanedihydroiodide (PDAI2), n-octylammonium iodide (n-OAI), piperazine dihydroiodide (PDI), phenethylammonium iodide (PEAI), and 3-methylthio-1-propanamine hydroiodide (3MPTAI), and has a thickness of 1-20 nm.

[0019] The electron transport layer is one of [6,6]-phenyl-C61-butyric acid methyl ester (PCBM), C 60 , 70 70, and has a film thickness of 10-40 nm.

[0020] The hole blocking layer is one of 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP), tin oxide (SnO x , x 2.0), and has a film thickness of 5-30 nm.

[0021] The metal electrode layer includes one or more of gold (Au), silver (Ag), copper (Cu), and aluminum (Al), and has a thickness of 50-200 nm.

[0022] The interface modification layer improves the contact between the hole transport layer or the transparent conductive substrate and the perovskite layer; wherein the perfluoro self-assembled molecules inhibit the vertical accumulation of other self-assembled molecules by their own electrostatic repulsion and the discrete confinement structure they form, making them more uniformly and completely cover the substrate. Specifically, the perfluoro self-assembled molecules that are coated first do not completely cover the surface of the substrate, forming a discrete distribution structure that is not completely continuous to separate the subsequent coating of other self-assembled molecules, i.e., the perfluoro self-assembled molecules as a frame to separate the compartments, and other self-assembled molecules occupy the uncovered area in the compartment, and the two together constitute a complete interface modification layer. The coverage of perfluoro self-assembled molecules on the substrate is 5-39%, the separation distance is 1.0-100 nm, and the thickness is 0.5-2.0 nm. The coverage of the interface modification layer ultimately composed of perfluoro self-assembled molecules and other self-assembled molecules on the surface of the substrate can reach 90-100%.

[0023] The preparation method of the perovskite solar cell based on the interface modification layer of the perfluoro self-assembled molecule is one of the following two methods:

[0024] The preparation of structure one comprises the following steps:

[0025] Step one: the conductive light-transmitting substrate is sequentially cleaned with glass cleaner, deionized water, acetone, isopropanol, ethanol, then soaked in ethanol, dried with nitrogen, and treated with ultraviolet ozone before use;

[0026] Step two: a hole transport layer dispersion solution with a concentration of 5-20 mg / mL is coated on the surface of the substrate, then heated on a hot table at 100-120°C for 5-20 minutes in an air environment with a relative humidity of 10-40%, to obtain a hole transport layer;

[0027] The nickel oxide (NiO x , x The solvent of the dispersion solution is one or more of water, methanol, ethanol, isopropanol, and propanol;

[0028] 20-100 microliters of the hole transport layer dispersion solution is coated on each 2.0-2.5 square centimeter substrate;

[0029] Step three: in a water-free, oxygen-free, and dust-free environment, a perfluoro self-assembled molecule solution with a concentration of 0.1-1.0 mg / mL is coated on the hole transport layer, then heated on a hot table at 80-120°C for 5-20 minutes; then another self-assembled molecule solution with a concentration of 0.2-2.0 mg / mL is coated on the obtained interface, to prepare an interface modification layer;

[0030] The solvents of the perfluoro self-assembled molecule solution and the other self-assembled molecule solution are the same, and are one or more of water, methanol, ethanol, isopropanol, and propanol;

[0031] Step four: in a water-free, oxygen-free, and dust-free environment, a perovskite precursor solution is coated on the obtained interface modification layer, a perovskite thin film is prepared by using an anti-solvent method or a vacuum flash method, the thickness of the thin film is 200-1000 nm, the substrate is removed and heated on a hot table at 80-120°C for 20-40 minutes, to prepare a perovskite light-absorbing layer;

[0032] 2-60 microliters of the perovskite precursor solution is added to each 2.0-2.5 square centimeter substrate;

[0033] The perovskite precursor solution is configured according to the components of the perovskite (Cs x MA y FA 1-x-y )Pb(I a Br 1-a)3 configuration, wherein, x 0.02-0.20, y is between 0.02-0.20, a is between 0.60-1.00, the solute is several of cesium iodide (CsI), lead iodide (PbI2), formamidine hydroiodide (FAI), methylamine hydroiodide (MAI), lead bromide (PbBr2), methylamine hydrobromide (MABr), and additional additives methylamine hydrochloride (MACl) (molar ratio 5-35%) and excess lead iodide (PbI2) (molar ratio 0-10%) are added, or a single crystal perovskite solute is directly formed, the solvent is a blended solvent of dimethylformamide (DMF) and dimethyl sulfoxide (DMSO), which can contain acetonitrile solvent, N-methyl pyrrolidone (NMP solvent) and γ-butyrolactone solvent, and the solution concentration is in the range of 0.8-1.7 mol / L;

[0034] Step five: in anhydrous, oxygen-free, dust-free environment, a concentration of 0.1-1.0 mg / mL interface passivation layer solution is coated on the perovskite light absorbing layer obtained above, and then heated on a hot stage at 80-120°C for 5-10 minutes to prepare an interface passivation layer with a thickness of 1-20 nm.

[0035] 2-60 microliters of interface passivation layer solution is added per 2.0-2.5 square centimeters of substrate;

[0036] The interface passivation layer uses one or two of 1,3-diaminopropane dihydroiodide (PDAI2), n-octylammonium iodide (n-OAI), piperazine dihydroiodide (PDI), phenethylammonium iodide (PEAI), and 3-methylthio-1-propylamine hydroiodide (3MPTAI), and one or more of water, methanol, ethanol, isopropanol, and propanol as the solvent;

[0037] Step six: spin coating an electron transport layer on the interface passivation layer or high vacuum 10 -4 The electron transport layer is prepared by vacuum deposition in an environment below 10

[0038] Step seven: spin coating or atomic layer deposition to prepare a hole blocking layer on the electron transport layer, or high vacuum 10 -4 The hole blocking layer is prepared by vacuum deposition in an environment below 10

[0039] Step eight: high vacuum 10 -4 The metal electrode layer is deposited in an environment below 10

[0040] The coating includes spin coating, blade coating, and slot coating methods.

[0041] Alternatively, the preparation of structure two includes the following steps:

[0042] Other steps are the same as method one, except that there is no step two, i.e. only step one, step three (the difference of this step is that the perfluoro self-assembly molecule solution with a concentration of 0.1-1.0 mg / mL is directly coated on the conductive and light-transmitting substrate), step four, step five, step six, step seven and step eight of method one are sequentially performed.

[0043] The substantial features of the present application are:

[0044] In the current technology, only a self-assembled monolayer is coated below the perovskite light-absorbing layer, or a device is prepared by a blending strategy of self-assembled molecules and other molecular materials to form a self-assembled molecular layer. However, due to the fact that the general self-assembled monomers are prone to self-aggregation and vertical stacking, cannot completely cover the substrate and are unevenly distributed, the subsequent perovskite light-absorbing layer directly contacts the substrate to cause an interface side reaction and an interface instability problem. Although the blending strategy can alleviate the problem of the self-assembled molecules not being able to completely cover the substrate and being unevenly distributed, since the multiple molecules have chemical interactions in the solution under the strategy, the other molecular materials do not have stability to be anchored on the substrate, and the precipitation process on the substrate is uncontrollable, resulting in randomness of the uniformity of the self-assembled molecules, which is not conducive to the formation of high-quality perovskite films. Therefore, the device prepared according to the existing technology has an unstable interface dynamic and poor thermal stability of the perovskite film, which restricts the further improvement of the efficiency and stability of the perovskite solar cell.

[0045] The newly added perfluoro self-assembled molecules and the self-assembled molecules are collectively referred to as an interface modification layer. The perfluoro self-assembled molecules which are not prone to self-aggregation are coated first to form a discrete distribution of a confined interface, which can promote the uniform coverage of other self-assembled molecules and inhibit their self-aggregation and vertical stacking, thereby improving the overall uniformity and coverage of the self-assembled molecules on the substrate. In addition, the perfluoro self-assembled molecules can have a strong interaction with the perovskite bottom interface. The perfluoro self-assembled molecules and FAI (formamidinium hydroiodide) in the perovskite components can form a hydrogen bond interaction, and the perfluoro self-assembled molecules and PbI2 in the perovskite can form a coordination and dipole interaction, so as to strengthen the interaction between the perovskite light-absorbing layer and the bottom interface, thereby improving the overall efficiency of the device to 26.84%, and the initial efficiency can still be maintained at 94.6% after 800 hours of 1-sun maximum power point tracking, and more than 95% of the initial efficiency can still be maintained after 1000 hours of storage at 65℃. 2+ and I -

[0046] In summary, the interface contact between the perovskite light-absorbing layer and the substrate can be further improved by the present application, the interface side reaction is inhibited, the non-radiative recombination caused by the interface defects is reduced, and the effects of improving the efficiency and stability of the device are achieved. ​

[0047] The present application has the following beneficial effects:

[0048] 1. The present application effectively reduces the self-aggregation behavior of other self-assembled molecules and improves their interface coverage on the substrate surface by introducing perfluoro self-assembled molecules to inhibit the vertical stacking of other self-assembled molecules. The interface modification layer formed by perfluoro self-assembled molecules and other self-assembled molecules can achieve 90-100% interface coverage, significantly improving the interface contact between the perovskite light-absorbing layer and the hole transport layer or conductive transparent substrate, and helping to improve the photoelectric conversion efficiency of perovskite solar cell devices to 26.84%;

[0049] 2. The interface modification layer formed by perfluoro self-assembled molecules and other self-assembled molecules in the present application effectively prevents direct contact between the perovskite active layer and the hole transport layer or conductive transparent substrate, significantly inhibits the adverse chemical reactions that may occur between the perovskite and metal oxides, and reduces the interface non-radiative recombination loss, thereby improving the device efficiency while enhancing its stability. After 800 hours of 1-sun maximum power point tracking, it can still maintain 94.6% of the initial efficiency;

[0050] 3. The interface modification layer formed in the present application has a regulating effect on the nucleation and crystal growth of perovskite thin films, which helps to achieve uniform deposition and high crystalline quality of the thin films, further improving the fill factor of the device to 86.61%, and thereby enhancing the photoelectric conversion efficiency;

[0051] 4. There is a strong interaction between the perfluoro self-assembled molecules and the perovskite active layer in the present application, which can enhance the bonding force of the bottom interface and effectively inhibit the thermal decomposition of the perovskite light-absorbing layer. After 1000 hours of storage at 65℃, the device can still maintain more than 95% of the initial efficiency, showing excellent long-term stability.

[0052] In summary, the present application can significantly improve the energy conversion efficiency and long-term stability of perovskite devices while ensuring low-cost device preparation, thus being very beneficial to the commercialization of perovskite solar cells. BRIEF DESCRIPTION OF DRAWINGS

[0053] Figure 1 The structure of four kinds of perovskite solar cell devices, namely, comparative group 1, experimental group 1, comparative group 2, and experimental group 2, is shown in the following figures: Figure 1 (a) is a schematic diagram of the device structure of comparative group 1 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 device structure of comparative group 2 with a hole transport layer, Figure 1 (d) is a schematic diagram of the device structure of experimental group 2 with a hole transport layer.

[0054] Figure 2 X-ray photoelectron spectroscopy of F 1s peak of the device modified by perfluoro (2-methyl-3-oxa) hexanoic acid in the control device (Control) and the experimental device (Target) of Example 2.

[0055] Figure 3 X-ray diffraction spectrum of other self-assembled molecules in the device modified by perfluoro (2-methyl-3-oxa) hexanoic acid in the control device of Comparative Example 2 and the experimental device of Example 2.

[0056] Figure 4 Top view (upper diagram) and side view (lower diagram) of the equilibrium heterojunction interface structure of the self-assembled molecule Me-4PACz in the control device (Control) and the device with preferential formation of confined interface on the surface of nickel oxide (Target) in the classical molecular dynamics simulation calculation of the control device of Comparative Example 2 and the experimental device of Example 2.

[0057] Figure 5 Coverage imaging diagram of the self-assembled molecule Me-4PACz on the (001) surface of nickel oxide and the (001) surface of nickel oxide with adsorbed PFA molecules in the classical molecular dynamics simulation calculation of the control device of Comparative Example 2 and the experimental device of Example 2.

[0058] Figure 6 Schematic diagram of the distribution of the interface modification layer of the self-assembled molecule of the control device of Comparative Example 2 and the experimental device of Example 2.

[0059] Figure 7 In-situ photoluminescence (PL) diagram during the spin coating process of the perovskite light absorbing layer of the control device of Comparative Example 2.

[0060] Figure 8 In-situ photoluminescence (PL) diagram during the spin coating process of the perovskite light absorbing layer of the experimental device of Example 2.

[0061] Figure 9 X-ray photoelectron spectroscopy of F 1s peak of the perovskite buried interface of the control device of Comparative Example 2 and the experimental device of Example 2.

[0062] Figure 10 X-ray photoelectron spectroscopy of Pb 4f peak of the perovskite buried interface of the control device of Comparative Example 2 and the experimental device of Example 2.

[0063] Figure 11 Photoluminescence mapping (PL mapping) diagram of the perovskite light absorbing layer buried interface of the control device of Comparative Example 2.

[0064] Figure 12Figure 2. Photoluminescence image of the buried bottom interface of the perovskite light absorbing layer of the experimental device of Example 2.

[0065] Figure 13 Figure 3. Scanning electron microscope image of the buried bottom interface of the perovskite light absorbing layer of the comparative device of Comparative Example 2.

[0066] Figure 14 Figure 4. Scanning electron microscope image of the buried bottom interface of the perovskite light absorbing layer of the experimental device of Example 2.

[0067] Figure 15 Figure 5. X-ray diffraction pattern of the perovskite thin film of the comparative device of Comparative Example 2 as a function of time when exposed to 85 °C, 40% relative humidity.

[0068] Figure 16 Figure 6. X-ray diffraction pattern of the perovskite thin film of the experimental device of Example 2 as a function of time when exposed to 85 °C, 40% relative humidity.

[0069] Figure 17 Figure 7. N-H stretching vibration peak of the attenuated total reflectance-Fourier transform infrared (ATR-FTIR) of the perovskite and PFA blend with perovskite of the comparative device of Comparative Example 2 and the experimental device of Example 2.

[0070] Figure 18 Figure 8. C-F stretching vibration peak of the attenuated total reflectance-Fourier transform infrared (ATR-FTIR) of the perovskite and PFA blend with perovskite of the comparative device of Comparative Example 2 and the experimental device of Example 2.

[0071] Figure 19 Figure 9. Current-voltage curve of the comparative device (Device A) of Comparative Example 1.

[0072] Figure 20 Figure 10. Current-voltage curve of the experimental device (Device B) of Example 1.

[0073] Figure 21 Figure 11. Current-voltage curve of the comparative device (Device C) of Comparative Example 2.

[0074] Figure 22 Figure 12. Current-voltage curve of the experimental device (Device D) of Example 2.

[0075] Figure 23 Figure 13. Current-voltage curve of the experimental device (Device E) of Example 3.

[0076] Figure 24 Figure 14. Current-voltage curve of the experimental device (Device F) of Example 4.

[0077] Figure 25 Figure 15. Current-voltage curve of the experimental device (Device G) of Example 5.

[0078] Figure 26 The current-voltage curves of the experimental group device (device H) in Example 6 are shown.

[0079] Figure 27 The current-voltage curves of the experimental group device (device I) in Example 7 are shown.

[0080] 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.

[0081] 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

[0082] Comparative Example 1:

[0083] 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:

[0084] 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.

[0085] 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.

[0086] 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 0.85MA 0.1 PbI3), spin-coating at 1000 rpm for 10 s followed by 5000 rpm for 30 s, using anti-solvent method by injecting 120 μL chlorobenzene at the 20th s of the 5000 rpm process using a pipette or dropper, and then removing the substrate and heating on a hot plate at 100℃ for 30 min, with a thickness of 790 nm;

[0087] 4. Preparing an interface passivation layer on the surface of the perovskite light-absorbing layer, specifically, using a pipette to take 25 μL of phenethylammonium iodate (PEAI) interface passivation layer solution (concentration of 2 mg / mL, solvent of isopropanol) at the 5th s of the 4000 rpm 30 s rotation process of the substrate, and dropping it to the center of the substrate in a rotating and dripping manner, with the dripping height limited to 0.5 cm, and then heating on a hot plate at 100℃ for 10 min after the dripping is completed, with a thickness of 1.5 nm;

[0088] 5. Vacuum deposition of a C -4 70 nm thick electron transport layer in an environment below 10 60 -3 Pa;

[0089] 6. Vacuum deposition of a BCP hole blocking layer in an environment below 10 -4 -3 Pa, with a thickness of 6.5 nm;

[0090] 7. Evaporation of an Ag metal electrode layer in an environment below 10 -4 -3 Pa, with a thickness of 150 nm, while keeping the evaporation environment within 50℃.

[0091] The prepared perovskite solar cell was tested for performance under a solar light intensity simulator, and the results are shown in FIG. 1 and Table 1. Figure 19 The short-circuit current was 25.30 mA / cm 2 , the open-circuit voltage was 1114 mV, the fill factor was 64.82%, and the energy conversion efficiency was 18.27%.

[0092] Example 1:

[0093] The device prepared in this example is the experimental group, named device B, and the structure of the experimental group device B is shown in FIG. 2B. Figure 1 (b), which is composed of ITO glass (1), 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 the preparation steps are as follows:

[0094] 1. The conductive and light-transmitting substrate (1.5 cm x 1.5 cm in size and 0.7 mm in thickness) was sequentially cleaned with glass cleaner, deionized water, acetone, isopropanol, ethanol, then soaked in ethanol, dried with nitrogen, and treated with ultraviolet ozone, and then stored for use;

[0095] 2. In anhydrous, oxygen-free, and dust-free environment, 50 μL of perfluoro (2-methyl-3-oxa) hexanoic acid solution (concentration 0.25 mg / mL, solvent ethanol) was coated on the conductive and light-transmitting substrate by means of a glove box device, and then heated on a hot stage at 100°C for 10 minutes; then 50 μL of other self-assembled molecule [4-(3,6-dimethyl-9H-carbazole-9-yl) butyl] phosphonic acid solution (concentration 0.5 mg / mL, solvent ethanol) was coated on the interface obtained above, to prepare an interface modification layer with a thickness of 1.3 nm;

[0096] 3. In anhydrous, oxygen-free, and dust-free environment, 50 μL of perovskite precursor solution (obtained by dissolving CsI, FAI, MAI, PbI2, and MACl in a mixed solvent in a molar ratio of 0.075:1.275:0.1497:1.65:0.186 and stirring for 5 h, the mixed solvent being a DMF and DMSO solution with a volume ratio of 4:1, the chemical composition of the precursor solution being Cs 0.05 FA 0.85 MA 0.1 PbI3) was spin-coated on the substrate at 1000 rpm for 10 s followed by 5000 rpm for 30 s, and then 120 μL of chlorobenzene was injected by means of a pipette or dropper at the 20th s of the 5000 rpm process, and the substrate was taken out and heated on a hot stage at 100°C for 30 minutes, with a thickness of 790 nm;

[0097] 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 2 mg / mL, solvent isopropanol) was taken by means of a pipette at the 5th s of the 4000 rpm 30 s rotation process of the substrate, and was dropped to the center of the substrate in a rotating and dropping manner, with the dropping height limited to 0.5 cm, and then heated on a hot stage at 100°C for 10 minutes after the dropping was completed, with a thickness of 1.5 nm;

[0098] 5. In an environment below 10 -4 Pa, a C 60 electron transport layer was prepared by vacuum deposition, with a thickness of 25 nm;

[0099] 6. In an environment below 10 -4 Pa, a BCP hole blocking layer was prepared by vacuum deposition, with a thickness of 6.5 nm;

[0100] 7. High vacuum 10 -4 The Ag metal electrode layer is evaporated in an environment below 10-6 Pa, the evaporation environment is kept within 50℃, and the evaporation thickness is 150 nm.

[0101] The prepared perovskite solar cell is tested for performance under a solar intensity simulator, and the results are shown in FIG. 1. Figure 20 The short circuit current is 25.30 mA / cm 2 The open circuit voltage is 1131 mV, the fill factor is 81.32%, and the energy conversion efficiency is 23.27%.

[0102] Comparative Example 2:

[0103] The device prepared in this example is a comparative group, named device C, and the structure of the comparative group device C is shown in FIG. 2. Figure 1 (c) which is composed of ITO glass (1), hole transport layer (9), self-assembled molecule layer (2), perovskite light absorption layer (3), interface passivation layer (4), electron transport layer (5), hole blocking layer (6), and metal electrode (7), and the preparation steps are as follows:

[0104] 1. The conductive light-transmitting substrate (1.5 cm x 1.5 cm in size and 0.7 mm in thickness) is sequentially cleaned with glass cleaner, deionized water, acetone, isopropanol, and ethanol, then immersed in ethanol, dried with nitrogen, and treated with ultraviolet ozone, and then reserved;

[0105] 2. 50 microliters of a dispersion solution of nickel oxide (NiO x , x with a concentration of 10 mg / mL is coated on the surface of the substrate, and then heated on a hot table at 100℃ for 10 minutes in an air environment with a relative humidity of 10-40%, to prepare a nickel oxide hole transport layer with a thickness of 4 nm;

[0106] 3. In an anhydrous, oxygen-free, and dust-free environment, which can generally be realized by a glove box device, 50 microliters of a self-assembled molecule [4-(3,6-dimethyl-9H-carbazole-9-yl)butyl] phosphonic acid solution (solvent: ethanol) with a concentration of 0.5 mg / mL is coated on the NiO x thin film to prepare a self-assembled molecule layer with a thickness of 1.1 nm;

[0107] 4. In anhydrous, oxygen-free, dust-free environment, which can be achieved by glove box equipment generally, spin 50 microliters of perovskite precursor solution (obtained by dissolving CsI, FAI, MAI, PbI2, MACl in mixed solvent according to the molar ratio of 0.075:1.275:0.1497:1.65:0.186 and stirring for 5 h, the mixed solvent is DMF and DMSO solution, the volume ratio of DMF and DMSO is 4:1, the chemical composition of the precursor solution is Cs 0.05 FA 0.85 MA 0.1 PbI3) on the substrate, spin at 1000 rpm for 10 s, then at 5000 rpm for 30 s, use anti-solvent method to inject 120 μL chlorobenzene at the 20th s of the process at 5000 rpm, take off the substrate and heat on a hot plate at 100℃ for 30 min, the thickness is 790 nm;

[0108] 5. Prepare an interface passivation layer on the surface of the perovskite light-absorbing layer, specifically, use a pipette to take 25 μL of PEAI interface passivation layer solution (concentration of 2 mg / mL, solvent is isopropanol) at the 5th s of the 4000 rpm 30 s rotation process on the substrate, and drop it to the center of the substrate in a rotating and dropping manner, the dropping height is limited to 0.5 cm, and after dropping, heat on a hot plate at 100℃ for 10 min, the thickness is 1.5 nm;

[0109] 6. In an environment below 10 -4 Pa, deposit C 60 electron transport layer by vacuum deposition, the thickness is 25 nm;

[0110] 7. In an environment below 10 -4 Pa, deposit BCP hole blocking layer by vacuum deposition, the thickness is 6.5 nm;

[0111] 8. Evaporate Ag metal electrode layer in an environment below 10 -4 Pa, keep the evaporation environment within 50℃, the evaporation thickness is 150 nm.

[0112] The preparation is completed to the end of step 2, take the sample for X-ray photoelectron spectroscopy test, the results are as shown in the following figure: Figure 2 (Control group), no fluorine element is detected on the surface of the hole transport layer. The preparation is completed to the end of step 3, take the sample for X-ray diffraction test, the results are as shown in the following figure: Figure 3 (Control group), other self-assembled molecules have diffraction peaks of longitudinal stacking. The top view (upper figure) and side view (lower figure) of the equilibrium heterojunction interface structure of the self-assembled molecule Me-4PACz on the nickel oxide (Control) calculated by classical molecular dynamics simulation are as shown in the following figure: Figure 4This 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.

[0113] 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.)

[0114] 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 .

[0115] The above tests show that there are interface side reactions, ion migration, non-radiation recombination, and major problems of being easily destroyed by external polar molecules between the bottom interface of the comparative device C and the perovskite active layer, thereby restricting the energy conversion efficiency and stability under working conditions of the device.

[0116] Embodiment 2:

[0117] The device prepared in this embodiment is an experimental group, named device D, and the structural schematic diagram of the experimental group device D is shown in FIG. 8. Figure 1 (d) is composed of ITO glass (1), hole transport layer (9), interface modification layer (8), perovskite light absorption layer (3), interface passivation layer (4), electron transport layer (5), hole blocking layer (6), and metal electrode (7), and the preparation steps are as follows:

[0118] 1. The conductive light-transmitting substrate (with a size of 1.5 cm x 1.5 cm and a thickness of 0.7 mm) is sequentially cleaned with glass cleaner, deionized water, acetone, isopropanol, and ethanol, then soaked in ethanol, dried with nitrogen, and treated with ultraviolet ozone for standby cleaning;

[0119] 2. 50 microliters of a dispersion solution of nickel oxide (NiO x , x The nickel oxide hole transport layer is prepared by coating 50 microliters of a dispersion solution of nickel oxide (NiO

[0120] 3. In an anhydrous, oxygen-free, and dust-free environment, which can generally be realized by a glove box device, 50 microliters of a solution of perfluoro (2-methyl-3-oxa) hexanoic acid (solvent: ethanol) with a concentration of 0.25 mg / mL is coated onto the NiO x thin film, and then heated on a hot plate at 100°C for 10 minutes; and then 50 microliters of a solution of other self-assembled molecules [4-(3, 6-dimethyl-9H-carbazole-9-yl) butyl] phosphonic acid (solvent: ethanol) with a concentration of 0.5 mg / mL is coated into the interface obtained above to prepare the interface modification layer with a thickness of 1.3 nm;

[0121] 4. In an anhydrous, oxygen-free, and dust-free environment, which can generally be realized by a glove box device, 50 microliters of a perovskite precursor solution (obtained by dissolving CsI, FAI, MAI, PbI2, and MACl in a mixed solvent in a molar ratio of 0.075:1.275:0.1497:1.65:0.186 and stirring for 5 h, the mixed solvent is a DMF and DMSO solution, the volume ratio of DMF and DMSO is 4:1, and the chemical composition of the precursor solution is Cs0.05 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.

[0122] 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.

[0123] 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;

[0124] 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.

[0125] 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.

[0126] 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 preferential formation of the confined interface (Target) by PFA molecules, calculated using classical molecular dynamics simulations, are attached. 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.

[0127] 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 12 The 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.)

[0128] 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 2The 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.

[0129] 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.

[0130] Example 3:

[0131] 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:

[0132] 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.

[0133] 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.

[0134] 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). xthin film, and then heated on a hot stage at 100°C for 10 minutes; 50 microliters of a solution of other self-assembled molecules [4-(3,6-dimethyl-9H-carbazol-9-yl)butyl] phosphonic acid (solvent: ethanol) with a concentration of 0.5 mg / mL was coated into the interface obtained above to prepare an interface modification layer with a thickness of 1.3 nm;

[0135] 4. In a water-free, oxygen-free, dust-free environment, which can generally be realized by a glove box device, 50 microliters of perovskite precursor solution (obtained by dissolving CsI, FAI, MAI, PbI2, MACl in a mixed solvent according to a molar ratio of 0.075:1.275:0.1497:1.65:0.186 and stirring for 5 h, the mixed solvent is a DMF and DMSO solution, the volume ratio of DMF and DMSO is 4:1, the chemical composition of the precursor solution is Cs 0.05 FA 0.85 MA 0.1 PbI3) was spin-coated on a substrate at 1000 rpm for 10 s and then at 5000 rpm for 30 s, and a reverse solvent method was used to inject 120 μL of chlorobenzene at the 20th s of the 5000 rpm process using a pipette or dropper, and the substrate was removed and heated on a hot stage at 100°C for 30 minutes, with a thickness of 790 nm;

[0136] 5. A PEAI interface passivation layer was prepared on the surface of the perovskite light-absorbing layer, specifically, 25 μL of interface passivation layer solution (concentration: 2 mg / mL, solvent: isopropanol) was taken with a pipette at the 5th s of the 4000 rpm 30 s rotation process of the substrate, and was dropped onto the center of the substrate in a rotating and dripping manner, with a dripping height limited to 0.5 cm, and after dripping was completed, heating was performed on a hot stage at 100°C for 10 min, with a thickness of 1.5 nm;

[0137] 6. In a high vacuum environment below 10 -4 Pa, a C 60 70 electron transport layer was prepared by vacuum deposition, with a thickness of 25 nm;

[0138] 7. In a high vacuum environment below 10 -4 Pa, a BCP hole blocking layer was prepared by vacuum deposition, with a thickness of 6.5 nm;

[0139] 8. In a high vacuum environment below 10 -4 Pa, an Ag metal electrode layer was deposited, with a deposition environment kept within 50°C, and a deposition thickness of 150 nm.

[0140] The prepared perovskite solar cell was tested for performance under a solar light intensity simulator, and the results are shown in the attached Figure 23 , with a current of 26.19 mA / cm 2, the open voltage is 1164 mV, the fill factor is 85.40%, and the energy conversion efficiency is 26.03%.

[0141] Example 4:

[0142] The device prepared in this example is an experimental group, named device F, and the structural diagram of the experimental group device F is shown in FIG. 8A. Figure 1 (d) is composed of ITO glass (1), hole transport layer (9), interface modification layer (8), perovskite light absorption layer (3), interface passivation layer (4), electron transport layer (5), hole blocking layer (6) and metal electrode (7), and the preparation steps are as follows:

[0143] 1. The conductive light-transmitting substrate (1.5 cm x 1.5 cm in size and 0.7 mm in thickness) was sequentially cleaned with glass cleaner, deionized water, acetone, isopropanol, ethanol, and then soaked in ethanol and dried with nitrogen. After being cleaned and dried, the substrate was treated with ultraviolet ozone and reserved for use.

[0144] 2. 50 microliters of nickel oxide (NiO x , x dispersion solution with a concentration of 10 mg / mL was coated on the surface of the substrate, and then heated on a hot stage at 100°C for 10 minutes in an air environment with a relative humidity of 10-40%, to prepare a nickel oxide hole transport layer with a thickness of 4 nm.

[0145] 3. In anhydrous, oxygen-free and dust-free environment, which can generally be realized by a glove box device, 50 microliters of perfluoro (2-methyl-3-oxa) hexanoic acid solution (solvent: ethanol) with a concentration of 0.5 mg / mL was coated on the NiO x thin film, and then heated on a hot stage at 100°C for 10 minutes; and then 50 microliters of other self-assembled molecule [4-(3,6-dimethyl-9H-carbazole-9-yl) butyl] phosphonic acid solution (solvent: ethanol) with a concentration of 0.5 mg / mL was coated in the interface obtained above, to prepare an interface modification layer with a thickness of 1.3 nm.

[0146] 4. In anhydrous, oxygen-free and dust-free environment, which can generally be realized by a glove box device, 50 microliters of perovskite precursor solution was spin-coated on the substrate (the perovskite precursor solution was obtained by dissolving CsI, FAI, MAI, PbI2 and MACl in a mixed solvent in a molar ratio of 0.075:1.275:0.1497:1.65:0.186 and stirring for 5 h, the mixed solvent was a DMF and DMSO solution, the volume ratio of DMF to DMSO was 4:1, and the chemical composition of the precursor solution was Cs 0.05 FA 0.85 MA 0.1PbI3), spin-coating at 1000 rpm for 10 s followed by 5000 rpm for 30 s, using anti-solvent method, 120 μL chlorobenzene was injected at the 20th s of the 5000 rpm process using a pipette or dropper, and the substrate was removed and heated on a hot plate at 100℃ for 30 min, with a thickness of 790 nm;

[0147] 5. PEAI interface passivation layer was prepared on the surface of perovskite light-absorbing layer, specifically, 25 μL of interface passivation layer solution (concentration of 2 mg / mL, solvent of isopropanol) was taken by a pipette at the 5th s of the 4000 rpm 30 s rotation process of the substrate, and was dropped to the center of the substrate in a rotating and dropping manner, with a dropping height limited to 0.5 cm, and after the dropping was completed, the substrate was heated on a hot plate at 100℃ for 10 min, with a thickness of 1.5 nm;

[0148] 6. A BCP hole-blocking layer was prepared by vacuum deposition in an environment with a pressure of 10 -4 Pa or below, with a thickness of 6.5 nm. 60 An electron transport layer was prepared by vacuum deposition in an environment with a pressure of 10

[0149] 7. A BCP hole-blocking layer was prepared by vacuum deposition in an environment with a pressure of 10 -4 Pa or below, with a thickness of 6.5 nm.

[0150] 8. An Ag metal electrode layer was deposited by vacuum deposition in an environment with a pressure of 10 -4 Pa or below, with a thickness of 150 nm.

[0151] The prepared perovskite solar cell was tested for performance under a solar light intensity simulator, and the results are shown in FIG. 2. Figure 24 The current was 26.11 mA / cm 2 , the open voltage was 1179 mV, the fill factor was 85.61%, and the energy conversion efficiency was 26.35%.

[0152] Example 5:

[0153] The device prepared in this example is an experimental group, named device G, and the structural diagram of the experimental group device G is shown in FIG. 3. Figure 1 (d), which comprises 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 the preparation steps are as follows:

[0154] 1. The conductive and light-transmitting substrate (with a size of 1.5 cm x 1.5 cm and a thickness of 0.7 mm) was sequentially cleaned with glass cleaner, deionized water, acetone, isopropanol, and ethanol, and then immersed in ethanol and dried with nitrogen. After being treated with ultraviolet ozone, it was ready for use.

[0155] 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.

[0156] 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.

[0157] 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.

[0158] 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.

[0159] 6. High vacuum 10 -4 C is prepared by vacuum deposition in environments below Pa. 60An electron transport layer with a thickness of 25 nm;

[0160] 7. High vacuum 10 -4 A BCP hole blocking layer was prepared by vacuum deposition in an environment below 10-6 Pa, and the thickness was 6.5 nm.

[0161] 8. High vacuum 10 -4 An Ag metal electrode layer was deposited in an environment below 10-6 Pa, and the deposition environment was maintained within 50°C. The thickness of the deposited layer was 150 nm.

[0162] The prepared perovskite solar cell was tested for performance under a solar light intensity simulator, and the results are shown in FIG. 6. Figure 25 The current was 25.76 mA / cm 2 The open voltage was 1163 mV, the fill factor was 84.88%, and the energy conversion efficiency was 25.43%.

[0163] Example 6:

[0164] The device prepared in this example is an experimental group, named device H. The structure of the experimental group device H is shown in FIG. 7. Figure 1 (d), which is composed of ITO glass (1), a hole transport layer (9), 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:

[0165] 1. The conductive light-transmitting substrate (with a size of 1.5 cm x 1.5 cm and a thickness of 0.7 mm) was sequentially cleaned with glass cleaner, deionized water, acetone, isopropanol, and ethanol, then immersed in ethanol, dried with nitrogen, and treated with ultraviolet ozone before use.

[0166] 2. 50 microliters of a nickel oxide (NiO x , x dispersion solution with a concentration of 10 mg / mL was coated on the surface of the substrate, and then heated on a hot stage at 100°C for 10 minutes in an air environment with a relative humidity of 10-40%, to prepare a nickel oxide hole transport layer with a thickness of 4 nm.

[0167] 3. In an anhydrous, oxygen-free, and dust-free environment, which can generally be achieved by a glove box device, 50 microliters of a perfluorooctylphosphonic acid solution (solvent: ethanol) with a concentration of 0.25 mg / mL was coated on the NiO xthin film, and then heated on a hot stage at 100°C for 10 minutes; 50 microliters of a solution of other self-assembled molecules [4-(3,6-dimethyl-9H-carbazol-9-yl)butyl] phosphonic acid (solvent: ethanol) with a concentration of 0.5 mg / mL was coated into the interface obtained above to prepare an interface modification layer with a thickness of 1.3 nm;

[0168] 4. In a water-free, oxygen-free, dust-free environment, which can generally be realized by a glove box device, 50 microliters of perovskite precursor solution (obtained by dissolving CsI, FAI, MAI, PbI2, MACl in a mixed solvent according to a molar ratio of 0.075:1.275:0.1497:1.65:0.186 and stirring for 5 h, the mixed solvent is a DMF and DMSO solution, the volume ratio of DMF and DMSO is 4:1, the chemical composition of the precursor solution is Cs 0.05 FA 0.85 MA 0.1 PbI3) was spin-coated on a substrate at 1000 rpm for 10 s and then at 5000 rpm for 30 s, and 120 μL of chlorobenzene was injected by using a pipette or dropper at the 20th s of the process at 5000 rpm by using an anti-solvent method, the substrate was taken out and heated on a hot stage at 100°C for 30 minutes, and the thickness was 790 nm;

[0169] 5. A PEAI interface passivation layer was prepared on the surface of the perovskite light-absorbing layer, specifically, 25 μL of interface passivation layer solution (concentration: 2 mg / mL, solvent: isopropanol) was taken by using a pipette at the 5th s of the process of rotating the substrate at 4000 rpm for 30 s, and was dropped to the center of the substrate in a rotating and dropping manner, the dropping height was limited to 0.5 cm, and after the dropping was completed, the substrate was heated on a hot stage at 100°C for 10 min, and the thickness was 1.5 nm;

[0170] 6. A C -4 70 nm electron transport layer was prepared by vacuum deposition in an environment below 10 60 Pa;

[0171] 7. A BCP hole blocking layer was prepared by vacuum deposition in an environment below 10 -4 Pa, and the thickness was 6.5 nm;

[0172] 8. An Ag metal electrode layer was evaporated in an environment below 10 -4 Pa, and the evaporation environment was kept within 50°C, and the evaporation thickness was 150 nm.

[0173] The prepared perovskite solar cell was tested under a solar light intensity simulator, and the results are shown in the attached Figure 26 , and the current was 25.80 mA / cm 2, the open voltage is 1156 mV, the fill factor is 84.29%, and the energy conversion efficiency is 25.14%.

[0174] Example 7:

[0175] The device prepared in this example is an experimental group, named device I, and the structural diagram of the experimental group device I is shown in FIG. 1. Figure 1 (d) is composed of ITO glass (1), hole transport layer (9), interface modification layer (8), perovskite light absorption layer (3), interface passivation layer (4), electron transport layer (5), hole blocking layer (6) and metal electrode (7), and the preparation steps are as follows:

[0176] 1. The conductive light-transmitting substrate (1.5 cm x 1.5 cm in size and 0.7 mm in thickness) was sequentially cleaned with glass cleaner, deionized water, acetone, isopropanol, ethanol, and then soaked in ethanol and dried with nitrogen, and then treated with ultraviolet ozone for standby cleaning;

[0177] 2. 50 microliters of nickel oxide (NiO x , x dispersion solution with a concentration of 10 mg / mL was coated on the surface of the substrate, and then heated on a hot stage at 100°C for 10 minutes in an air environment with a relative humidity of 10-40%, to prepare a nickel oxide hole transport layer with a thickness of 4 nm;

[0178] 3. In an anhydrous, oxygen-free, dust-free environment, which can generally be achieved by a glove box device, 50 microliters of perfluoro (2-methyl-3-oxa) hexanoic acid solution (solvent: ethanol) with a concentration of 0.25 mg / mL was coated on the NiO x thin film, and then heated on a hot stage at 100°C for 10 minutes; and then 50 microliters of other self-assembled molecule [4-(3,6-dimethyl-9H-carbazole-9-yl) butyl] phosphonic acid solution (solvent: ethanol) with a concentration of 0.5 mg / mL was coated in the interface obtained above, to prepare an interface modification layer with a thickness of 1.3 nm;

[0179] 4. In an anhydrous, oxygen-free, dust-free environment, which can generally be achieved by a glove box device, 50 microliters of perovskite precursor solution (obtained by dissolving CsI, FAI, MAI, PbI2, MACl in a mixed solvent in a molar ratio of 0.075:1.275:0.1497:1.65:0.186 and stirring for 5 h, the mixed solvent is DMF and DMSO solution, the volume ratio of DMF and DMSO is 4:1, and the chemical composition of the precursor solution is Cs 0.05 FA 0.85 MA 0.1PbI3), spin-coating at 1000 rpm for 10 s followed by 5000 rpm for 30 s, using anti-solvent method, 120 μL chlorobenzene was injected at the 20th s of 5000 rpm process using a pipette or dropper, the substrate was removed and heated on a hot plate at 100℃ for 30 min, the thickness was 790 nm;

[0180] 5. Interfacial passivation layer was prepared on the surface of perovskite light-absorbing layer, specifically, 25 μL of PEAI interfacial passivation layer solution (concentration of 2 mg / mL, solvent of isopropanol) was taken by a pipette at the 5th s of 4000 rpm 30 s rotation process of the substrate, and was dropped to the center of the substrate in a rotating and dropping manner, the dropping height was limited to 0.5 cm, after dropping, the substrate was heated on a hot plate at 100℃ for 10 min, the thickness was 1.5 nm;

[0181] 6. High vacuum 10 -4 Pa below, C 60 s was prepared by vacuum deposition, the thickness was 25 nm;

[0182] 7. High vacuum 10 -4 Pa below, SnO x 2 was prepared by atomic layer deposition, the thickness was 25 nm; x

[0183] 8. Ag metal electrode layer was evaporated in a high vacuum environment below 10 -4 Pa, the evaporation environment was kept below 50℃, the evaporation thickness was 150 nm.

[0184] The prepared perovskite solar cell was tested under a solar light intensity simulator, the results are shown in the following table: Figure 27 The short-circuit current was 26.21 mA / cm 2 , the open-circuit voltage was 1178 mV, the fill factor was 86.20%, and the energy conversion efficiency was 26.61%.

[0185] The remaining matters of the present application are known technologies.​

Claims

1. A perovskite solar cell based on a self-assembled molecule of perfluorinated as an interface modification layer, characterized in that, The battery is one of the following two structures: Structure one, from bottom to top, is conductive and light-transmitting substrate, hole transport layer, interface modification layer, perovskite light-absorbing layer, interface passivation layer, electron transport layer, hole blocking layer and metal electrode layer; Or, structure two, from bottom to top, is conductive and light-transmitting substrate, interface modification layer, perovskite light-absorbing layer, interface passivation layer, electron transport layer, hole blocking layer and metal electrode layer; The interface modification layer is composed of perfluoro self-assembled molecules and other self-assembled molecules, which are arranged alternately on the substrate, with a distribution ratio of 1:100-1:1.5 and a total film thickness of 1-4 nm; The perfluoro self-assembled molecules are selected from at least one of perfluoro (2-methyl-3-oxa) hexanoic acid, perfluoro-2, 5-dimethyl-3, 6-dioxane heptanoic acid, perfluoro octanoic acid and perfluoro octyl phosphonic acid; The other self-assembled molecules are substance A or substance B; Substance A is one or more of [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 polymer-[2-(3, 6-poly-9H-carbazole-9-yl) ethyl] phosphonic acid and polymer-[4-(3, 6-poly-9H-carbazole-9-yl) butyl] phosphonic acid, with a polymer molecular weight of 1000-100000.

2. The perovskite solar cell based on the interface modification layer of perfluorinated self-assembled molecules according to claim 1, characterized in that, In the interface modification layer, the perfluoro self-assembled molecules are the framework of the compartment, and the other self-assembled molecules occupy the uncovered area in the compartment, and the two together constitute a complete interface modification layer; wherein the coverage of perfluoro self-assembled molecules on the substrate is 5-39%, the interval distance is 1.0-100 nm, and the thickness is 0.5-2.0 nm, and finally the interface modification layer composed of perfluoro self-assembled molecules and other self-assembled molecules on the substrate surface can reach 90-100%.

3. The perovskite solar cell based on the interface modification layer of perfluorinated self-assembled molecules according to claim 1, characterized in that, The base material of the conductive and light-transmitting substrate uses rigid glass, flexible substrate polyethylene terephthalate, polyethylene naphthalate, polyimide, and the light-transmitting conductive layer above uses fluorine-doped tin oxide with a thickness of 300-1000 nm, or indium-doped tin oxide with a thickness of 50-150 nm; The material of the hole transport layer is nickel oxide or polytriazine, 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, wherein x 0.02-0.20, y is between 0.02-0.20, a is between 0.60-1.00, and the film thickness is 200-1000 nm; The interface passivation layer uses one or two of 1, 3-diaminopropane dihydroiodide, n-octyl ammonium iodide, piperazine dihydroiodide, phenethyl ammonium iodide and 3-methylthio-1-propanamine hydroiodide, with a thickness of 1-20 nm; The electron transport layer is one of [6,6]-phenyl-C61-butyric acid isomethyl ester, C 60 70 70 with 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, with a film thickness of 3-30 nm; The metal electrode layer comprises one or more of gold, silver, copper and aluminum, and has a thickness of 50-200 nm.

4. The perovskite solar cell based on the interface modification layer of perfluorinated self-assembled molecules according to claim 1, characterized in that, The interface modification layer improves the contact between the hole transport layer or the transparent conductive substrate and the perovskite layer; wherein the perfluoro self-assembled molecules inhibit the vertical accumulation of other self-assembled molecules by their own electrostatic repulsion and the discrete confinement structure formed thereby, so that they more uniformly and completely cover the substrate.

5. The method for preparing perovskite solar cell based on interface modification layer of perfluorinated self-assembly molecule according to claim 1, characterized in that, One of the following two methods is adopted: The preparation of structure one comprises the following steps: Step one: the conductive and light-transmitting substrate is sequentially cleaned with glass cleaner, deionized water, acetone, isopropanol and ethanol, then immersed in ethanol, dried with nitrogen, treated with ultraviolet ozone, and then reserved; Step two: a hole transport layer dispersion solution with a concentration of 5-20 mg / mL is coated on the surface of the substrate, then heated on a hot table at 100-120 DEG C for 5-20 minutes in an air environment with a relative humidity of 10-40%, to obtain a hole transport layer; The solvent of the hole transport layer dispersion solution is one or more of water, methanol, ethanol, isopropanol and propanol; 20-100 microliters of nickel oxide dispersion solution is coated on every 2.0-2.5 square centimeter of substrate; Step three: in a water-free, oxygen-free and dust-free environment, a perfluoro self-assembled molecule solution with a concentration of 0.1-1.0 mg / mL is coated on the hole transport layer, then heated on a hot table at 80-120 DEG C for 5-20 minutes; then a solution of other self-assembled molecules with a concentration of 0.2-2.0 mg / mL is coated on the interface obtained above, to prepare an interface modification layer; The solvent of the perfluoro self-assembled molecule solution and the solution of other self-assembled molecules is one or more of water, methanol, ethanol, isopropanol and propanol; Step four: in a water-free, oxygen-free and dust-free environment, a perovskite precursor solution is coated on the interface modification layer obtained above, to prepare a perovskite thin film by using an anti-solvent method or a vacuum flash method, the thickness of the thin film is 200-1000 nm, the substrate is taken out and heated on a hot table at 80-120 DEG C for 20-40 minutes, to prepare a perovskite light-absorbing layer; 2-60 microliters of perovskite precursor solution is added to every 2.0-2.5 square centimeter of substrate; Step five: in a water-free, oxygen-free and dust-free environment, an interface passivation layer solution with a concentration of 0.1-1.0 mg / mL is coated on the perovskite light-absorbing layer obtained above, then heated on a hot table at 80-120 DEG C for 5-10 minutes, to prepare an interface passivation layer with a thickness of 1-20 nm; 2-60 microliters of interface passivation layer solution is added to every 2.0-2.5 square centimeter of substrate; The interface passivation layer adopts one or two of 1,3-diaminopropane dihydroiodide, n-octylammonium iodide, piperazine dihydroiodide, phenethylammonium iodide and 3-methylthio-1-propanamine hydroiodide, the solvent is one or more of water, methanol, ethanol, isopropanol and propanol, and the thickness is 1-20 nm; Step six: spin-coating an electron transport layer or high vacuum on the interface passivation layer10 -4 In a Pd environment, the electron transport layer is prepared by vacuum deposition, with a thickness of 10-40 nm; Step seven: on the electron transport layer, a hole blocking layer is prepared by spin coating or atomic layer deposition, or high vacuum 10 -4 In the environment below Pa, a hole blocking layer is prepared by vacuum evaporation deposition, with a thickness of 5-30 nm; Step eight: high vacuum 10 -4 The metal electrode layer is evaporated in a Pa below environment, and the evaporation thickness is 50-200 nm. The coating includes spin coating method, blade coating method and slot coating method; Alternatively, the preparation of structure two comprises the following steps: Other steps are the same as Method 1, except that there is no Step 2, i.e. there is only Step 1, Step 3, Step 4, Step 5, Step 6, Step 7 and Step 8 in Method 1 in turn; wherein, Step 3 is different from Step 3 in that the perfluorinated self-assembled molecule solution with a concentration of 0.1-1.0 mg / mL is directly coated onto the conductive and light-transmitting substrate.

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

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