Perovskite solar cell and preparation method thereof, laminated cell, photovoltaic module and electric equipment

Abstract

The invention provides a perovskite solar cell and a preparation method thereof, a laminated cell, a photovoltaic module and electric equipment. The perovskite solar cell comprises a perovskite layer, a first passivation layer located on one side of the perovskite layer, and a second passivation layer located on the other side of the perovskite layer. The first passivation layer and the second passivation layer respectively and independently comprise elements in the perovskite layer; the mass percentage content of elements in the perovskite layer in the first passivation layer is greater than or equal to 88%; and the mass percentage content of elements in the perovskite layer in the first passivation layer is greater than or equal to 88%. The photoelectric conversion efficiency of the perovskite solar cell can be improved.

Description

Technical Field

[0001] The present invention belongs to the field of battery technology, and in particular relates to a perovskite solar cell and a preparation method thereof, a stacked cell, a photovoltaic module and an electrical device. Background Art

[0002] Perovskite solar cells have attracted widespread attention in the field of optoelectronic materials in recent years, primarily due to their excellent light absorption properties, tunable band gap, and relatively low manufacturing costs. Perovskite materials typically have high absorption coefficients and long carrier diffusion lengths, which enable efficient light absorption and charge separation in relatively thin film layers. Furthermore, the manufacturing process for perovskite solar cells is relatively simple and can be achieved through low-temperature methods such as solution processing, which opens up the possibility of large-scale production and commercial application.

[0003] However, perovskite solar cells in the prior art generally have the problem of low photoelectric conversion efficiency. Summary of the Invention

[0004] The main purpose of the present invention is to provide a perovskite solar cell with high photoelectric conversion efficiency.

[0005] The present invention also provides a method for preparing a perovskite solar cell, which can prepare the above-mentioned perovskite solar cell, has a simple process and low cost.

[0006] The present invention also provides a stacked cell comprising the above-mentioned perovskite solar cell, so that the stacked cell has a higher photoelectric conversion efficiency.

[0007] The present invention also provides a photovoltaic module, comprising the above-mentioned perovskite solar cell or stacked cell, so that the performance of the related cells of the photovoltaic module is relatively excellent.

[0008] The present invention also provides an electrical device comprising the above-mentioned battery. Therefore, the performance of the battery associated with the electrical device is relatively excellent.

[0009] In a first aspect, the present invention provides a perovskite solar cell, comprising a perovskite layer, a first passivation layer located on one side of the perovskite layer, and a second passivation layer located on the other side of the perovskite layer; the first passivation layer and the second passivation layer each independently comprise elements in the perovskite layer;

[0010] The mass percentage of the elements in the perovskite layer in the first passivation layer is ≥88%;

[0011] The mass percentage of the elements in the perovskite layer in the second passivation layer is ≥88%.

[0012] The perovskite solar cell as described above, wherein the mass percentage of the elements in the perovskite layer in the first passivation layer is 90%-95%;

[0013] And / or, the mass percentage of the elements in the perovskite layer in the second passivation layer is 95%-99%.

[0014] The perovskite solar cell as described above, wherein the perovskite layer comprises a perovskite material, and the chemical composition of the perovskite material is ABX3, wherein A comprises at least one of methylamine ion, formamidine ion, and cesium ion, B comprises lead ion and / or tin ion, and X comprises at least one of iodide ion, bromide ion, and chloride ion;

[0015] The elements in the perovskite layer include element A, element B and element X.

[0016] The perovskite solar cell as described above, wherein the first passivation layer and the second passivation layer each independently comprise a phosphonic acid group;

[0017] The ratio of the concentration of the phosphonic acid groups in the first passivation layer to the concentration of the second passivation layer is (3-10):1.

[0018] In the perovskite solar cell as described above, in the deep-section element distribution curve of the perovskite solar cell, the relative intensity of the phosphonic acid group in the first passivation layer is 3×10 -3 au-5×10 -2 au;

[0019] And / or, the relative intensity of the phosphonic acid groups in the second passivation layer is 5×10 -4 au-5×10 -3 au.

[0020] As described above, the difference in defect state density of the perovskite solar cell before and after passivation is 50%-85%.

[0021] In the perovskite solar cell as described above, the ratio of the thickness of the first passivation layer to the thickness of the second passivation layer is (10-100):1.

[0022] The perovskite solar cell as described above, wherein the thickness of the first passivation layer is 50 nm to 100 nm;

[0023] And / or, the thickness of the second passivation layer is 1 nm-5 nm.

[0024] In the perovskite solar cell as described above, the passivation material in the first passivation layer and the second passivation layer is the same.

[0025] The perovskite solar cell as described above, wherein the passivation material comprises a hydrophilic functional group and a hydrophobic functional group;

[0026] Preferably, the hydrophilic functional group includes at least one of a phosphonic acid group, a hydroxyl group, a carboxyl group, an amino group, a sulfonic acid group, and a silane group;

[0027] And / or, the hydrophobic functional group includes at least one of a substituted or unsubstituted alkyl group and a substituted or unsubstituted aromatic group.

[0028] The perovskite solar cell as described above, the passivation material in the first passivation layer includes at least one of 4-(3,6-dimethyl-9-hydrogen-carbazole-9-yl)phenyl)phosphonic acid, 4-(3,6-dimethoxy-9-hydrogen-carbazole-9-yl)phenyl)phosphonic acid, [4-(2,7-dibromo-9,9-dimethylacridin-10(9-hydrogen)-yl)butyl]phosphonic acid, (2-(9H-carbazole-9-yl)ethyl)phosphonic acid, 2,3,4,5,6-pentafluorobenzylphosphonic acid, [2-(3,6-diphenyl-9-hydrogen-carbazole-9-yl)ethyl]phosphonic acid, [4-(3,6-dibromo-9-hydrogen-carbazole-9-yl)butyl]phosphonic acid, and [2-(3,6-dibromo-9-hydrogen-carbazole-9-yl)ethyl]phosphonic acid;

[0029] And / or, the passivation material in the second passivation layer includes at least one of 4-(3,6-dimethyl-9-hydrogen-carbazole-9-yl)phenyl)phosphonic acid, 4-(3,6-dimethoxy-9-hydrogen-carbazole-9-yl)phenyl)phosphonic acid, [4-(2,7-dibromo-9,9-dimethylacridine-10(9-hydrogen)-yl)butyl]phosphonic acid, (2-(9H-carbazole-9-yl)ethyl)phosphonic acid, 2,3,4,5,6-pentafluorobenzylphosphonic acid, [2-(3,6-diphenyl-9-hydrogen-carbazole-9-yl)ethyl]phosphonic acid, [4-(3,6-dibromo-9-hydrogen-carbazole-9-yl)butyl]phosphonic acid, and [2-(3,6-dibromo-9-hydrogen-carbazole-9-yl)ethyl]phosphonic acid.

[0030] In the perovskite solar cell as described above, the thickness of the perovskite layer is 400nm-800nm, preferably 500nm-700nm.

[0031] The perovskite solar cell as described above further includes a hole transport layer located on the side of the first passivation layer facing away from the perovskite layer, a first electrode located on the side of the hole transport layer facing away from the perovskite layer, and an electron transport layer, a hole blocking layer, and a second electrode located in sequence on the side of the second passivation layer facing away from the hole transport layer.

[0032] The perovskite solar cell as described above, wherein the thickness of the hole transport layer is 20 nm to 50 nm;

[0033] and / or the hole transport layer comprises at least one of nitrogen oxide, poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine], [2-(3,6-dimethoxy-9H-carbazol-9-yl)ethyl]phosphonic acid, [2-(9H-carbazol-9-yl)ethyl]phosphonic acid, [4-(3,6-dimethyl-9H-carbazol-9-yl)butyl]phosphonic acid, and [4-(9H-carbazol-9-yl)butyl]phosphonic acid;

[0034] And / or, the first electrode includes at least one of indium tin oxide, fluorine-doped tin oxide, and aluminum-doped zinc oxide;

[0035] and / or, the electron transport layer comprises at least one of [6,6]-phenyl-C61-butyric acid methyl ester, fullerene, and tin dioxide;

[0036] and / or, the hole blocking layer comprises at least one of 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline, titanium oxide, and zinc oxide;

[0037] And / or, the second electrode includes at least one of gold, silver, copper, aluminum, a carbon electrode, indium tin oxide, and indium zinc oxide.

[0038] In a second aspect, the present invention provides a method for preparing the perovskite solar cell as described above, comprising the following steps:

[0039] While forming the perovskite layer, the first passivation layer is formed on one side of the perovskite layer, and the second passivation layer is formed on the other side of the perovskite layer to obtain the perovskite solar cell.

[0040] The method for preparing a perovskite solar cell as described above, wherein while forming the perovskite layer, the first passivation layer is formed on one side of the perovskite layer, and the second passivation layer is formed on the other side of the perovskite layer, to obtain the perovskite solar cell, comprises:

[0041] A perovskite precursor solution is coated on the hole transport layer, and an anti-solvent solution containing a passivation material is added to the perovskite precursor solution during the coating process.

[0042] In the method for preparing a perovskite solar cell as described above, adding an anti-solvent solution containing a passivation material to the perovskite precursor solution during the coating process comprises:

[0043] 5s-10s before the end of coating, an anti-solvent solution containing a passivation material is added to the perovskite precursor solution.

[0044] The method for preparing a perovskite solar cell as described above, wherein the anti-solvent comprises at least one solvent selected from the group consisting of ethanol, isopropanol, toluene, chlorobenzene, chloroform, ethyl acetate, dimethylformamide, and dimethyl sulfoxide;

[0045] And / or, the concentration of the passivation material in the anti-solvent solution is 0.01 mg / mL-10 mg / mL, preferably 0.2 mg / mL-5 mg / mL.

[0046] The method for preparing a perovskite solar cell as described above further includes: sequentially forming an electron transport layer, a hole blocking layer, and a second electrode on the second passivation layer.

[0047] In a third aspect, the present invention provides a stacked cell, comprising the perovskite solar cell as described above, or a perovskite solar cell prepared according to the method for preparing a perovskite solar cell as described above.

[0048] In a fourth aspect, the present invention provides a photovoltaic module, comprising the perovskite solar cell as described above, or a perovskite solar cell prepared according to the method for preparing a perovskite solar cell as described above, or the stacked cell as described above.

[0049] In a fifth aspect, the present invention provides an electrical device comprising the photovoltaic module described above.

[0050] In the perovskite solar cell provided by the present invention, the first passivation layer and the second passivation layer contain elements in the perovskite layer, and the content of the elements in the perovskite layer included in the first passivation layer and the second passivation layer is limited. The interaction of these elements can effectively fill the interface defects of the perovskite layer, reduce the formation of non-radiative recombination centers, and achieve effective passivation of the upper and lower interfaces of the perovskite layer, thereby significantly improving the photoelectric conversion efficiency of the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] To more clearly illustrate the technical solutions in the embodiments of the present invention or related technologies, the following briefly introduces the drawings required for use in the embodiments of the present invention or related technologies. Obviously, the drawings described below are only some embodiments of the present invention. Those skilled in the art can also derive other drawings based on these drawings without inventive effort.

[0052] Figure 1 A schematic structural diagram of a perovskite solar cell provided by the present invention;

[0053] Figure 2 This is a cross-sectional SEM image of the dual-interface passivated perovskite thin film device of Example 1;

[0054] Figure 3A deep-section three-dimensional element distribution map of a perovskite solar cell, where: Figure 3 (a) is a deep-section three-dimensional element distribution diagram of the perovskite solar cell of Comparative Example 2, Figure 3 (b) is a deep-section three-dimensional element distribution diagram of the perovskite solar cell of Example 1;

[0055] Figure 4 This is a deep-section element distribution curve of a perovskite solar cell, where: Figure 4 (a) is a deep-section element distribution curve of the perovskite solar cell of comparative example 2, Figure 4 (b) is a deep-section element distribution curve of the perovskite solar cell of Example 1;

[0056] Figure 5 is the space charge limited current curve of the perovskite solar cell, where Figure 5 (a) is the space charge limited current curve of the perovskite solar cell of comparative example 1, Figure 5 (b) is the space charge limited current curve of the perovskite solar cell of Comparative Example 2; Figure 5 (c) is the space charge limited current curve of the perovskite solar cell of Example 1. DETAILED DESCRIPTION

[0057] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0058] Over the past few years, perovskite solar cells have become a frontier in photovoltaic research due to their significant advantages in high efficiency, large area, and low-cost fabrication. The unique properties of perovskite materials allow for their manufacture via scalable solution processing at low temperatures, significantly reducing production costs and paving the way for large-scale commercial applications. With the continuous improvement of material stability, the industrialization of perovskite solar cells is rapidly advancing.

[0059] Perovskite layers are typically prepared by dissolving the perovskite components in a solvent at a specific ratio, thoroughly mixing them, and then subjecting them to mesophase crystallization and thermal annealing to form a polycrystalline film. While this process is simple and effective, polycrystalline perovskite layers prepared by the solution method often exhibit numerous defects. These defects, primarily due to uneven crystallization and interfacial instabilities, lead to increased carrier recombination, thereby reducing the photovoltaic conversion efficiency of the cell.

[0060] To improve the quality of the perovskite layer, researchers have optimized the crystallization process and introduced additives to modify the crystallization kinetics of the perovskite film. These methods help form perovskite grains that extend throughout the entire cross-section and reduce defects in the bulk phase. However, defects at the upper and lower interfaces of the perovskite layer remain a significant problem and require further passivation treatment. Interface defects can lead to non-radiative recombination of charge carriers, thereby reducing the photovoltaic efficiency of the cell.

[0061] The inventors of this application have discovered that the prior art typically employs a separate passivation method, which involves introducing separate passivation layers on the upper and lower sides of the perovskite layer. While this method has improved the performance of perovskite solar cells to a certain extent, it still has some limitations, resulting in lower-than-expected photoelectric conversion efficiency. To further improve the photoelectric conversion efficiency of the cell, it is urgently necessary to develop an efficient dual-interface passivation method that allows for better interaction between the elements in the perovskite layer and the passivation layer, significantly reducing carrier recombination caused by interface defects and improving the photoelectric conversion efficiency of perovskite solar cells.

[0062] Based on this, in a first aspect, the present invention provides a perovskite solar cell, comprising a perovskite layer, a first passivation layer located on one side of the perovskite layer, and a second passivation layer located on the other side of the perovskite layer; the first passivation layer and the second passivation layer each independently include elements in the perovskite layer; the mass percentage of the elements in the perovskite layer in the first passivation layer is ≥88%, for example, it can be 88%, 89%, 90%, 91%, 92%, 95%, 97%, 99%, 99.9% or a range consisting of any two thereof; the mass percentage of the elements in the perovskite layer in the second passivation layer is ≥88%, for example, it can be 88%, 89%, 90%, 91%, 92%, 95%, 97%, 99%, 99.9% or a range consisting of any two thereof.

[0063] In the present invention, the first passivation layer is located below the perovskite layer, and the second passivation layer is located above the perovskite layer.

[0064] In the present invention, the first and second passivation layers each independently comprise elements from the perovskite layer, and the mass percentage of the elements from the perovskite layer in the first and second passivation layers is ≥88%. This interaction of elements can effectively fill interface defects, reduce the formation of non-radiative recombination centers, and effectively passivate the upper and lower interfaces of the perovskite layer, thereby significantly improving the photoelectric conversion efficiency of the battery. Furthermore, the elements in the perovskite layer can form stable chemical bonds with the elements in the passivation layer, further enhancing the chemical stability of the interface. This stability not only improves the efficiency of the battery but also extends its service life. Furthermore, this interaction of elements can better match the energy band structure, reduce energy loss, and improve charge transfer efficiency. The high mass percentage of elements in the perovskite layer can form a more efficient charge transfer path, reduce charge retention at the interface, and improve charge extraction efficiency.

[0065] Therefore, in the perovskite solar cell provided by the present invention, the first passivation layer and the second passivation layer include elements in the perovskite layer; and the content of the elements in the perovskite layer included in the first passivation layer and the second passivation layer is limited, which can improve the photoelectric conversion efficiency of the perovskite solar cell.

[0066] The present invention can test the types and distribution of elements in the first passivation layer, the second passivation layer and the perovskite layer by time-resolved secondary ion mass spectrometry, and test the types and contents of elements in the first passivation layer, the second passivation layer and the perovskite layer by energy dispersive X-ray spectroscopy (EDS).

[0067] In some embodiments of the present invention, the mass percentage of the elements in the perovskite layer in the first passivation layer is 90%-95%, for example, it can be 90%, 91%, 92%, 94%, 95% or a range consisting of any two thereof.

[0068] In some embodiments, the mass percentage of the elements in the perovskite layer in the second passivation layer is 95-99%, for example, it can be 95%, 96%, 97%, 98%, 99% or a range consisting of any two thereof.

[0069] The present invention reduces lattice mismatch at the interface by introducing an appropriate amount of perovskite layer elements into the passivation layer. This chemical and structural compatibility helps reduce interface defect density, minimize non-radiative recombination, and increase carrier lifetime, thereby improving the photoelectric conversion efficiency of perovskite solar cells.

[0070] In some embodiments of the present invention, the perovskite layer includes a perovskite material having a chemical composition of ABX3, wherein A is a monovalent cation, specifically methylamine ion (CH3NH3 + , MA + ), formamidinium ion (HC(NH2)2+ , FA + ), cesium ions (Cs + ), B is a divalent cation, specifically lead ion (Pb 2+ ) and / or tin ions (Sn 2 + ), X is a monovalent anion, which may specifically include iodide ion (I - ), bromide ion (Br - ), chloride ion (Cl - ) at least one of; the elements in the perovskite layer include element A, element B and element X.

[0071] Perovskite materials include the above-mentioned elements, which can achieve better interaction with the elements in the passivation layer, effectively fill interface defects, reduce the formation of non-radiative recombination centers, and achieve effective passivation of the upper and lower interfaces of the perovskite layer, thereby significantly improving the photoelectric conversion efficiency of the battery.

[0072] In some embodiments of the present invention, the first passivation layer and the second passivation layer each independently include phosphonic acid groups; the ratio of the concentration of the phosphonic acid groups in the first passivation layer and the second passivation layer is (3-10):1, for example, it can be 3:1, 5:1, 7:1, 9:1, 10:1 or a range consisting of any two of them.

[0073] It can be understood that the passivation materials in the first passivation layer and the second passivation layer of the present invention both include phosphonic acid groups, and the concentration of the phosphonic acid groups can represent the concentration of the passivation material.

[0074] In the present invention, the ratio of the concentration of the phosphonic acid groups in the first passivation layer and the second passivation layer is within the above range, which can achieve differentiated passivation of the upper and lower interfaces of the perovskite layer, which is conducive to achieving the best passivation effect on the two interfaces, thereby maximizing the photoelectric conversion efficiency of the perovskite solar cell.

[0075] In the present invention, the ratio of the concentrations of the phosphonic acid groups in the first passivation layer and the second passivation layer can be obtained by the following method:

[0076] A time-resolved secondary ion mass spectrometer (TOF-SIMS) was used to perform deep element distribution analysis on perovskite solar cells, and a deep element distribution curve was obtained. In the curve, the ratio of the relative intensity of the phosphonic acid groups in the first passivation layer to the relative intensity of the phosphonic acid groups in the second passivation layer is the ratio of the concentrations of the phosphonic acid groups in the first passivation layer and the second passivation layer.

[0077] In some embodiments of the present invention, in the deep-section element distribution curve of the perovskite solar cell, the relative intensity of the phosphonic acid group in the first passivation layer is 3×10 -3 au-5×10-2 au, for example, can be 3×10 -3 au, 5×10 -3 au, 7×10 -3 au, 9×10 -3 au, 2×10 -2 au, 5×10 -2 au or a range consisting of any two of them.

[0078] In some embodiments, the relative intensity of the phosphonic acid groups in the second passivation layer is 5×10 -4 au-5×10 - 3 au, for example, can be 5×10 -4 au, 7×10 -4 au, 9×10 -4 au, 1×10 -3 au, 3×10 -3 au, 5×10 -3 au or a range consisting of any two of them.

[0079] In the deep-section element distribution curve, the intensity of the phosphonic acid group can reflect its concentration and distribution in the passivation layer. The phosphonic acid group can form a stable chemical bond with the uncoordinated ions or defect sites in the perovskite material, thereby effectively passivating the interface defects, reducing the non-radiative recombination of carriers at the interface, and improving the photoelectric conversion efficiency of the perovskite solar cell. The phosphonic acid group also affects the energy level structure of the interface, optimizes the band alignment, helps reduce the energy loss of carriers at the interface, and promotes the effective separation and transfer of charges. In addition, the phosphonic acid group can also improve the chemical stability of the interface and reduce the impact of environmental factors (such as moisture and oxygen) on the perovskite material, thereby extending the service life of the battery.

[0080] In some embodiments of the present invention, the difference in defect state density of the perovskite solar cell before and after passivation is 50%-85%, for example, it can be 50%, 60%, 70%, 80%, 85% or any two thereof.

[0081] In the present invention, the difference in defect state density of the perovskite solar cell before and after passivation is within the above range, which can reduce non-radiative recombination, and more photogenerated electrons and holes can be collected to the electrode, thereby improving the photoelectric conversion efficiency of the perovskite solar cell.

[0082] The difference in defect state density of the perovskite solar cell before and after passivation can be measured by the following method:

[0083] By using the space charge limited current method (SCLC), single carrier devices (such as ITO / SnO2 / PVK / PCBM / Ag) are constructed. Figure 5 As shown in the figure, the threshold voltage (V TFL ), the carrier defect state density can be calculated by the following formula:

[0084]

[0085] Where ε0 is the dielectric constant of vacuum, usually 8.854×10 -12 F / cm; ε is the relative dielectric constant of the perovskite layer, usually in the range of 6-70, and is taken as 50 here; L is the thickness of the perovskite layer, in m; e is the electron charge, usually 1.6×10 -19 C.

[0086] Defect state density difference = (carrier defect density before passivation - carrier defect density after passivation) / carrier defect density before passivation.

[0087] In some embodiments of the present invention, the ratio of the thickness of the first passivation layer to the second passivation layer is (10-100):1, for example, it can be 10:1, 30:1, 40:1, 60:1, 80:1, 100:1 or a range consisting of any two thereof.

[0088] In the present invention, the ratio of the thickness of the first passivation layer to the second passivation layer is within the above range, which can achieve differentiated passivation of the upper and lower interfaces of the perovskite layer, specifically reducing interface defects. Furthermore, the thickness of the passivation layer affects the charge transfer path and efficiency. An appropriate thickness ratio can optimize the band alignment of the interface, reduce energy loss during charge transfer, and improve charge separation efficiency. Furthermore, the thickness of the passivation layer also affects the optical properties of the battery, such as reflectivity and transmittance. By adjusting the thickness ratio, light absorption and utilization can be optimized, improving photoelectric conversion efficiency.

[0089] The present invention can test the thickness of the first passivation layer and the second passivation layer by using a scanning electron microscope.

[0090] In some embodiments of the present invention, the thickness of the first passivation layer is 50 nm-100 nm, for example, 50 nm, 60 nm, 70 nm, 80 nm, 90 nm, 100 nm or a range consisting of any two thereof.

[0091] In some embodiments, the thickness of the second passivation layer is 1 nm-5 nm, for example, 1 nm, 2 nm, 3 nm, 4 nm, 5 nm, or a range consisting of any two thereof.

[0092] In the present invention, the thickness of the first and second passivation layers can effectively passivate interface defects without significantly increasing the charge transfer path, thereby maintaining high charge transfer efficiency. Furthermore, while ensuring the passivation effect, it also maintains good charge transfer characteristics, reduces carrier recombination and energy loss in the passivation layer, and improves the photoelectric conversion efficiency of the perovskite solar cell.

[0093] In some embodiments of the present invention, the passivation material in the first passivation layer and the second passivation layer is the same, which can further improve the photoelectric conversion efficiency of the perovskite solar cell.

[0094] In some embodiments of the present invention, the passivation material includes a hydrophilic functional group and a hydrophobic functional group; preferably, the hydrophilic functional group includes at least one of a phosphonic acid group, a hydroxyl group, a carboxyl group, an amino group, a sulfonic acid group, and a silane group.

[0095] In some embodiments, the hydrophobic functional group includes at least one of a substituted or unsubstituted alkyl group and a substituted or unsubstituted aromatic group.

[0096] In the present invention, the hydrophilic functional groups can effectively bind to the surface of the perovskite material, reducing surface defects and non-radiative recombination, thereby improving the photoelectric conversion efficiency of the perovskite solar cell. The hydrophobic functional groups help improve the moisture resistance and environmental stability of the passivation layer, preventing moisture from invading the perovskite layer and extending its service life. The synergistic effect of the hydrophilic and hydrophobic functional groups optimizes the interface between the perovskite layer and the passivation layer, improving charge transfer efficiency.

[0097] Specifically, the passivation material in the first passivation layer includes at least one of 4-(3,6-dimethyl-9-hydrogen-carbazole-9-yl)phenyl)phosphonic acid, 4-(3,6-dimethoxy-9-hydrogen-carbazole-9-yl)phenyl)phosphonic acid, [4-(2,7-dibromo-9,9-dimethylacridine-10(9-hydrogen)-yl)butyl]phosphonic acid, (2-(9H-carbazole-9-yl)ethyl)phosphonic acid, 2,3,4,5,6-pentafluorobenzylphosphonic acid, [2-(3,6-diphenyl-9-hydrogen-carbazole-9-yl)ethyl]phosphonic acid, [4-(3,6-dibromo-9-hydrogen-carbazole-9-yl)butyl]phosphonic acid, and [2-(3,6-dibromo-9-hydrogen-carbazole-9-yl)ethyl]phosphonic acid.

[0098] In some embodiments, the passivation material in the second passivation layer includes at least one of 4-(3,6-dimethyl-9H-carbazole-9-yl)phenyl)phosphonic acid, 4-(3,6-dimethoxy-9H-carbazole-9-yl)phenyl)phosphonic acid, [4-(2,7-dibromo-9,9-dimethylacridin-10(9H)-yl)butyl]phosphonic acid, (2-(9H-carbazole-9-yl)ethyl)phosphonic acid, 2,3,4,5,6-pentafluorobenzylphosphonic acid, [2-(3,6-diphenyl-9H-carbazole-9-yl)ethyl]phosphonic acid, [4-(3,6-dibromo-9H-carbazole-9-yl)butyl]phosphonic acid, and [2-(3,6-dibromo-9H-carbazole-9-yl)ethyl]phosphonic acid.

[0099] The above-mentioned passivation materials can effectively passivate defects and grain boundaries on the surface of the perovskite layer, reduce non-radiative recombination, facilitate the extraction and transport of carriers, and improve the photoelectric conversion efficiency of perovskite solar energy.

[0100] In some embodiments of the present invention, the thickness of the perovskite layer is 400 nm to 800 nm, for example, 400 nm, 500 nm, 600 nm, 700 nm, 800 nm, or any two thereof, preferably 500 nm to 700 nm. This ensures sufficient light absorption and improves photoelectric conversion efficiency. When the thickness of the perovskite layer is 500 nm to 700 nm, the photoelectric conversion efficiency of the perovskite solar cell can be further improved.

[0101] The present invention can test the thickness of the perovskite layer by means of a scanning electron microscope.

[0102] In some embodiments of the present invention, the perovskite solar cell further includes a hole transport layer located on a side of the first passivation layer facing away from the perovskite layer, a first electrode located on a side of the hole transport layer facing away from the perovskite layer, and an electron transport layer, a hole blocking layer, and a second electrode located in sequence on a side of the second passivation layer facing away from the hole transport layer.

[0103] In some embodiments of the present invention, the thickness of the hole transport layer is 20 nm to 50 nm, for example, 20 nm, 30 nm, 35 nm, 40 nm, 50 nm, or any combination thereof. This can optimize the selective transport of holes, reduce electron recombination, and facilitate the formation of a high-quality interface, reducing interface defects.

[0104] In the present invention, the thickness of the hole transport layer can be tested by a scanning electron microscope.

[0105] In some embodiments, the hole transport layer includes at least one of nitrogen oxide, poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine], [2-(3,6-dimethoxy-9H-carbazol-9-yl)ethyl]phosphonic acid, [2-(9H-carbazol-9-yl)ethyl]phosphonic acid, [4-(3,6-dimethyl-9H-carbazol-9-yl)butyl]phosphonic acid, and [4-(9H-carbazol-9-yl)butyl]phosphonic acid.

[0106] The above-mentioned hole transport materials have excellent hole transport capabilities and can further improve the photoelectric conversion efficiency of perovskite solar cells.

[0107] In the present invention, the first electrode (or transparent conductive electrode) collects holes transported by the hole transport layer and conducts them out of the battery. The first electrode comprises at least one of indium tin oxide (ITO), fluorine-doped tin oxide (FTO), and aluminum-doped zinc oxide (AZO).

[0108] The electron transport layer can extract and transport photogenerated electrons from the perovskite layer while blocking the transmission of holes, thereby improving the photoelectric conversion efficiency of the battery. It can also passivate defects on the surface of the perovskite layer, reducing non-radiative recombination and improving the stability and photoelectric conversion efficiency of the battery.

[0109] In some embodiments, the electron transport layer includes at least one of [6,6]-phenyl-C61-butyric acid methyl ester (PC61BM), fullerene (C60), and tin dioxide (SnO2).

[0110] The hole blocking layer can prevent holes from moving toward the cathode (second electrode), avoiding problems such as leakage, thereby further optimizing the performance of perovskite solar cells.

[0111] In some embodiments, the hole blocking layer includes at least one of 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP), titanium oxide (TiO 2 ), and zinc oxide (ZnO).

[0112] The second electrode (also called the top electrode or current collector) has high conductivity and can effectively collect and transmit current, reduce series resistance, and improve the fill factor (FF). It can also reflect unabsorbed light back to the perovskite layer, increasing light absorption and current density.

[0113] In some embodiments, the second electrode includes at least one of gold, silver, copper, aluminum, a carbon electrode, indium tin oxide (ITO), and indium zinc oxide (IZO).

[0114] In a second aspect, the present invention provides a method for preparing the perovskite solar cell as described above, comprising the following steps:

[0115] While forming the perovskite layer, a first passivation layer is formed on one side of the perovskite layer, and a second passivation layer is formed on the other side of the perovskite layer to obtain a perovskite solar cell.

[0116] In the present invention, in-situ passivation is performed during the formation of the perovskite layer, achieving simultaneous passivation of the upper and lower interfaces of the perovskite layer. This results in a perovskite solar cell, where a first passivation layer forms at the lower interface and a second passivation layer forms at the upper interface. Due to gravity and the effects of hydrophilic functional groups, the first passivation layer contains a higher mass of passivation material, while the second passivation layer contains a lower mass of passivation material. This perovskite solar cell exhibits a higher photoelectric conversion efficiency. This method simplifies the process, reduces process steps and experimental variables, and improves experimental reproducibility.

[0117] In some embodiments of the present invention, while forming the perovskite layer, forming a first passivation layer on one side of the perovskite layer and forming a second passivation layer on the other side of the perovskite layer, to obtain a perovskite solar cell includes:

[0118] A perovskite precursor solution is coated on the hole transport layer, and an antisolvent solution containing a passivation material is added to the perovskite precursor solution during the coating process.

[0119] In one embodiment, a hole transport layer can be first deposited on the first electrode by magnetron sputtering, and then a perovskite layer can be deposited by a coating method, specifically a spin coating method, and an anti-solvent solution containing a passivation material is added to the perovskite precursor solution during the coating process. The rapid precipitation of the intermediate phase of the perovskite layer proceeds with the anti-solvent extrusion process, starting from the upper interface and diffusing to the lower interface. The hydrophilic or hydrophobic functional groups in the passivation material give it orientation. When the perovskite crystallizes, most of it is squeezed to the upper and lower interfaces of the perovskite layer, thereby completing the preparation of a perovskite solar cell with a double-interface passivation structure, so that the hole transport layer and the perovskite layer have good matching properties, and the preparation method is simple, and the resulting perovskite solar cell has a high photoelectric conversion efficiency.

[0120] In some embodiments of the present invention, adding an antisolvent solution containing a passivation material to the perovskite precursor solution during the coating process comprises:

[0121] 5s-10s before the end of coating, an anti-solvent solution containing a passivation material is added to the perovskite precursor solution.

[0122] 5-10 seconds before the coating process is complete, i.e., nearing the end of the coating process, an antisolvent solution containing a passivation material is added to the coating perovskite precursor solution. The antisolvent rapidly induces the nucleation and growth of perovskite crystals while simultaneously introducing the passivation material to the upper and lower interfaces of the perovskite layer. The addition of the antisolvent rapidly reduces the solubility in the solution, promoting the rapid nucleation and growth of perovskite crystals, and forming a high-quality perovskite film. With the help of the antisolvent, the passivation material is introduced to the interface of the perovskite layer, effectively filling interfacial defects, reducing non-radiative recombination of charge carriers, and improving the photoelectric conversion efficiency of the perovskite solar cell. By performing passivation simultaneously during the coating process, additional process steps are eliminated, the manufacturing process is simplified, and production efficiency is improved.

[0123] In some embodiments of the present invention, the anti-solvent includes at least one of ethanol, isopropanol, toluene, chlorobenzene, chloroform, ethyl acetate, dimethylformamide, dimethyl sulfoxide and the like.

[0124] In some embodiments, the concentration of the passivating material in the antisolvent solution is 0.01 mg / mL-10 mg / mL, for example, 0.01 mg / mL, 0.05 mg / mL, 0.1 mg / mL, 1 mg / mL, 2 mg / mL, 3 mg / mL, 4 mg / mL, 5 mg / mL, 6 mg / mL, 7 mg / mL, 8 mg / mL, 9 mg / mL, 10 mg / mL or any two thereof, preferably 0.2 mg / mL-5 mg / mL.

[0125] The concentration of the passivation material can effectively fill interface defects, reduce non-radiative recombination of carriers, and improve the photoelectric conversion efficiency of perovskite solar cells. When the concentration of the passivation material in the antisolvent is 0.2mg / mL-5mg / mL, the photoelectric conversion efficiency of the perovskite solar cell can be further improved.

[0126] In the present invention, the passivation material is dissolved in the anti-solvent, and the stirring temperature during mixing can be 20° C.-60° C., and the stirring time is 1 hour-24 hours.

[0127] In some embodiments of the present invention, the further embodiment further includes: sequentially forming an electron transport layer, a hole blocking layer, and a second electrode on the second passivation layer.

[0128] In the present invention, the material of the electron transport layer, for example, C60, can be formed into the electron transport layer on the surface of the second passivation layer by an evaporation method.

[0129] Subsequently, a hole blocking layer material, for example, BCP, may be deposited on the surface of the electron transport layer to form a hole blocking layer.

[0130] Subsequently, a second electrode can be formed on the surface of the hole blocking layer through evaporation technology to produce a perovskite solar cell.

[0131] In the embodiments of the present invention, unless otherwise specified, the processes involved, such as spin coating and evaporation technology, may be conventional operations in the art and are not particularly limited thereto.

[0132] When forming each layer of the perovskite solar cell in the present invention, the solvent used includes at least one of N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), 2-Mercaptoethanol (2-ME), and N-methylpyrrolidone (NMP).

[0133] In a third aspect, the present invention provides a stacked cell, comprising the perovskite solar cell as described above, or a perovskite solar cell prepared according to the method for preparing a perovskite solar cell as described above, which has corresponding advantages to the above-mentioned perovskite solar cell and will not be described in detail.

[0134] It can be understood that perovskite tandem cells include but are not limited to silicon / perovskite tandem cells, full perovskite tandem cells, copper indium gallium selenide and other thin film cells / perovskite tandem cells.

[0135] In some embodiments, the perovskite tandem cell is a silicon / perovskite tandem cell. Furthermore, the silicon / perovskite tandem cell includes a top cell and a bottom cell arranged one above the other, wherein the top cell is the aforementioned perovskite solar cell and the bottom cell is a silicon cell. Furthermore, the top cell and the bottom cell are arranged in series. Furthermore, the silicon cell includes a back conductive metal electrode, a bottom transparent conductive layer, a p-type amorphous silicon layer, a first intrinsic amorphous silicon layer, a silicon wafer, a second intrinsic amorphous silicon layer, and an n-type amorphous silicon layer, stacked in sequence.

[0136] In some embodiments, the silicon / perovskite stack cell includes, from bottom to top, a back conductive metal electrode, a transparent conductive layer, a p-type amorphous silicon layer, a first intrinsic amorphous silicon layer, a silicon wafer, a second intrinsic amorphous silicon layer, an n-type amorphous silicon layer, a first electrode, the above-mentioned hole transport layer, a perovskite layer, a passivation layer, an electron transport layer, a hole blocking layer and a second electrode.

[0137] In a fourth aspect, the present invention provides a photovoltaic module, comprising the perovskite solar cell as described above, or a perovskite solar cell prepared according to the method for preparing a perovskite solar cell as described above, or a stacked cell as described above, which has corresponding advantages to the above-mentioned perovskite solar cell and will not be repeated.

[0138] It can be understood that photovoltaic modules can be used in photovoltaic power stations, such as ground power stations, rooftop power stations, water surface power stations, etc., and can also be used in equipment or devices that use solar energy to generate electricity, such as user solar power supplies, solar street lights, solar cars, solar buildings, etc. It can also be understood that the application scenarios of photovoltaic systems include but are not limited to this, that is, photovoltaic systems can be used in all fields that require solar energy to generate electricity. Taking the photovoltaic power generation system network as an example, the photovoltaic system may include a photovoltaic array, a junction box and an inverter. The photovoltaic array can be an array combination of multiple photovoltaic modules. For example, multiple photovoltaic modules can form multiple photovoltaic arrays. The photovoltaic array is connected to the junction box. The junction box can converge the current generated by the photovoltaic array. The converged current flows through the inverter to be converted into the alternating current required by the mains power grid and then connected to the mains power network to achieve solar power supply.

[0139] The photovoltaic modules provided in this application can be used in, but are not limited to, electrical devices such as vehicles, ships, or aircraft.

[0140] In a fifth aspect, the present invention provides an electrical device comprising the photovoltaic module described above.

[0141] The electrical equipment of the present invention can be conventional electrical equipment in the field, such as power equipment (such as electric vehicles), electronic equipment (such as computers, mobile phones, digital cameras, printers, fax machines, etc.), wearable devices (such as watches, bracelets, VR glasses, etc.), household appliances (such as air conditioners, refrigerators, washing machines, microwave ovens, etc.), etc., without special restrictions.

[0142] The technical solution of the present invention is further described below with reference to specific embodiments.

[0143] Example 1

[0144] The structural diagram of the perovskite solar cell in this embodiment is as follows Figure 1 As shown, it includes a first electrode, a hole transport layer, a first passivation layer, a perovskite layer, a second passivation layer, an electron transport layer, a hole blocking layer and a second electrode which are stacked in sequence.

[0145] The method for preparing a perovskite solar cell of this embodiment includes the following steps:

[0146] 1) The ITO glass was ultrasonically cleaned with isopropyl alcohol, acetone, deionized water, and ethanol for 20 minutes in sequence. After drying, the surface was treated with plasma for 500 seconds to improve substrate wettability.

[0147] 2) NiO x It is deposited on the ITO surface by magnetron sputtering process. The sputtering process is pure Ar atmosphere, the coating pressure is 0.8pa, and the sputtering power is 300W for 25 times to form a hole transport layer.

[0148] 3) Dissolve Me-pPhPACz in isopropanol solution at a concentration of 0.5 mg / mL.

[0149] 4) Perovskite (1.2M Cs 0.1 MA 0.05 FA 0.85 PbI 0.95 Br 0.05 ) Preparation of precursor solution: Dissolve a certain amount of FAI, CsI, MABr, PbBr2, and PbI2 in a mixed solvent of DMF:DMSO (volume ratio is 4:1) and stir thoroughly to mix. Then, the perovskite precursor solution is deposited on the ITO / NiO by spin coating. x The spin coating speed was 3000 rpm for 40 s, and 100 μL of the isopropanol solution containing Me-pPhPACz prepared in step 3) was added dropwise 10 s before the end of the spin coating. The perovskite mesophase film was then annealed at 120° C. for 30 min to form a first passivation layer, a perovskite layer, and a second passivation layer in sequence on the hole transport layer.

[0150] 5) The sample of step 4) was transferred to a vacuum coating chamber, and a 30 nm thick C60 as an electron transport layer and a 6 nm thick BCP as a hole blocking layer were sequentially deposited on the second passivation layer by thermal evaporation to form a double-interface passivated perovskite thin film device, such as Figure 2 shown.

[0151] 6) A 120 nm thick silver electrode was deposited on the hole blocking layer by vacuum thermal evaporation to form a second electrode, thereby obtaining a perovskite solar cell.

[0152] The first passivation layer of the perovskite solar cell includes elements such as Pb, I, C, N, P, O, H, Cs, etc., and the second passivation layer includes elements such as Pb, I, C, N, P, O, H, Cs, etc.

[0153] Example 2

[0154] The preparation methods of the perovskite solar cell in Example 2 are basically the same as those in Example 1, except that, in step 3), Br-4PACz is dissolved in an ethanol solution at a concentration of 2 mg / mL.

[0155] Example 3

[0156] The preparation method of the perovskite solar cell in Example 3 is basically the same as that in Example 1, except that, in step 3), the concentration of Me-pPhPACz in the isopropanol solution is changed to 0.2 mg / ml.

[0157] Example 4

[0158] The preparation method of the perovskite solar cell in Example 4 is basically the same as that in Example 1, except that, in step 3), the concentration of Me-pPhPACz in the isopropanol solution is changed to 5 mg / ml.

[0159] Example 5

[0160] The preparation method of the perovskite solar cell in Example 5 is basically the same as that in Example 1, except that, in step 3), the concentration of Me-pPhPACz in the isopropanol solution is changed to 12 mg / ml.

[0161] Example 6

[0162] The preparation method of the perovskite solar cell in Example 6 is basically the same as that in Example 1, except that the concentration of the perovskite precursor solution and the deposition process are changed so that the thickness of the perovskite layer is 400 nm.

[0163] Example 7

[0164] The preparation method of the perovskite solar cell in Example 7 is basically the same as that in Example 1, except that the concentration of the perovskite precursor solution and the deposition process are changed so that the thickness of the perovskite layer is 800 nm.

[0165] Example 8

[0166] The preparation method of the perovskite solar cell in Example 8 is basically the same as that in Example 1, except that the sputtering deposition thickness of nickel oxide is changed to 50 nm.

[0167] Comparative Example 1

[0168] The preparation method of the perovskite solar cell of Comparative Example 1 comprises the following steps:

[0169] 1) Same as Example 1.

[0170] 2) Same as Example 1.

[0171] 3) Perovskite (1.2M Cs 0.1 MA 0.05 FA 0.85 PbI 0.95 Br 0.05 ) Preparation of precursor solution: Dissolve a certain amount of FAI, CsI, MABr, PbBr2, and PbI2 in a mixed solvent of DMF:DMSO (volume ratio is 4:1) and stir thoroughly to mix. Then, the perovskite precursor solution is deposited on the ITO / NiO by spin coating. xThe spin coating speed was 3000 rpm for 40 s, and 100 μL of isopropanol solution was added 10 s before the end of spin coating. The perovskite mesophase film was then annealed at 120° C. for 30 min to form a perovskite layer on the hole transport layer.

[0172] 4) The sample from step 3) was transferred to a vacuum coating chamber, and a 30 nm thick C60 as an electron transport layer and a 6 nm thick BCP as a hole blocking layer were sequentially deposited on the second passivation layer by thermal evaporation.

[0173] 5) A 120 nm thick silver electrode was deposited on the hole blocking layer by vacuum thermal evaporation to form a second electrode, thereby obtaining a perovskite solar cell.

[0174] Comparative Example 2

[0175] The preparation method of the perovskite solar cell of Comparative Example 2 comprises the following steps:

[0176] 1) Same as Example 1.

[0177] 2) Same as Example 1.

[0178] 3) Me-pPhPACz was dissolved in isopropanol solution at a concentration of 0.5 mg / mL and deposited onto NiO by spin coating. x The film was deposited on the substrate at a speed of 2000 rpm for 30 s, and then annealed at 100° C. for 10 min to form a passivation layer.

[0179] 4) Perovskite (1.2M Cs 0.1 MA 0.05 FA 0.85 PbI 0.95 Br 0.05 ) Preparation of precursor solution: Dissolve a certain amount of FAI, CsI, MABr, PbBr2, and PbI2 in a mixed solvent of DMF:DMSO (volume ratio is 4:1) and stir thoroughly to mix. Then, the perovskite precursor solution is deposited on the ITO / NiO by spin coating. x / Me-pPhPACz was spin-coated at a speed of 3000 rpm for 40 s. 100 μL of isopropanol solution was added dropwise 10 s before the end of spin coating. The perovskite mesophase film was then annealed at 120 °C for 30 min to form a perovskite layer on the passivation layer.

[0180] 5) Same as Example 1.

[0181] 6) Same as Example 1.

[0182] Comparative Example 3

[0183] The preparation method of the perovskite solar cell of Comparative Example 3 comprises the following steps:

[0184] 1) Same as Example 1.

[0185] 2) Same as Example 1.

[0186] 3) Dissolve Br-4PACz in ethanol solution at a concentration of 2 mg / ml and deposit it onto NiO by spin coating. x The film was deposited on the substrate at a speed of 2000 rpm for 30 s, and then annealed at 100° C. for 10 min to form a passivation layer.

[0187] 4) Perovskite (1.2M Cs 0.1 MA 0.05 FA 0.85 PbI 0.95 Br 0.05 Precursor solution preparation: Dissolve a certain amount of FAI, CsI, MABr, PbBr2, and PbI2 in a DMF:DMSO (4:1 by volume) mixture and stir thoroughly to mix thoroughly. The perovskite precursor solution is then spin-coated onto the ITO / NiOX / Br-4PACz substrate at 3000 rpm for 40 seconds. Add 100 μL of isopropanol solution 10 seconds before the end of the spin coating. The perovskite mesophase film is then annealed at 120°C for 30 minutes to form a perovskite layer on the passivation layer.

[0188] 5) Same as Example 1.

[0189] 6) Same as Example 1.

[0190] Comparative Example 4

[0191] The preparation method of the perovskite solar cell of Comparative Example 4 comprises the following steps:

[0192] 1) Same as Example 1.

[0193] 2) Same as Example 1.

[0194] 3) Me-pPhPACz was dissolved in isopropanol solution at a concentration of 0.5 mg / mL and deposited onto NiO by spin coating. x The film was deposited on the substrate at a speed of 2000 rpm for 30 s, and then annealed at 100° C. for 10 min to form a first passivation layer.

[0195] 4) Perovskite (1.2M Cs 0.1 MA 0.05 FA 0.85 PbI 0.95 Br 0.05) Preparation of precursor solution: Dissolve a certain amount of FAI, CsI, MABr, PbBr2, and PbI2 in a mixed solvent of DMF:DMSO (volume ratio is 4:1) and stir thoroughly to mix. Then, the perovskite precursor solution is deposited on the ITO / NiO by spin coating. x / Me-pPhPACz was spin-coated at a speed of 3000 rpm for 40 s. 100 μL of isopropanol solution was added dropwise 10 s before the end of spin coating. The perovskite mesophase film was then annealed at 120 °C for 30 min to form a perovskite layer on the first passivation layer.

[0196] 5) Me-pPhPACz was dissolved in isopropanol solution at a concentration of 0.01 mg / mL and deposited on the perovskite layer by spin coating at a speed of 3000 rpm for 30 seconds, followed by annealing at 80°C for 10 minutes to form a second passivation layer.

[0197] 6) The deposition method of the electron transport layer and the hole blocking layer is the same as that in Example 1.

[0198] 7) The deposition method of the second electrode is the same as that of Example 1.

[0199] Test example:

[0200] 1. Types and contents of elements in the first passivation layer and the second passivation layer: The types and distribution of elements in the first passivation layer, the second passivation layer and the perovskite layer were tested by time-resolved secondary ion mass spectrometry, and the types and contents of elements in the first passivation layer, the second passivation layer and the perovskite layer were tested by energy dispersive X-ray spectroscopy (EDS).

[0201] 2. Relative intensities of phosphonic acid groups in the first and second passivation layers: Time-resolved secondary ion mass spectrometry (TOF-SIMS) was used to perform a depth profile test on the perovskite solar cell, generating a deep profile element distribution curve. From this curve, the relative intensities of the phosphonic acid groups in the first and second passivation layers can be determined. Test mode: negative ion spectrum mode; experimental conditions: primary ion beam: Bi 3+ , 30keV, 45° incidence, scanning area: 70μm×70μm, pixel 128×128, beam current 0.48pA, sputtering ion beam: Cs, 2keV, 45° incidence, sputtering area 210μm×210μm, etching time 450s, strong In on the ITO substrate was measured - Signal stopped; device model: ULVAC-PHI nanoTOF 3+.

[0202] 3. Thickness: The thickness of the first passivation layer, the second passivation layer, the hole transport layer, and the perovskite layer were measured using a scanning electron microscope (SEM). Equipment model: HITACHI SU8010.

[0203] 4. Difference in defect state density before and after passivation: By using the space charge limited current method (SCLC), a single carrier device (such as ITO / SnO2 / PVK / PCBM / Ag) is constructed. Figure 5 As shown ( Figure 5 (a) is the space charge limited current curve of the perovskite solar cell of comparative example 1, Figure 5 (b) is the space charge limited current curve of the perovskite solar cell of Comparative Example 2; Figure 5 (c) is the space charge limited current curve of the perovskite solar cell of Example 1), and the critical voltage (V) in the trap filling region (TFL) is obtained by changing the slope of the current-voltage (IV) curve. TFL ), the carrier defect state density can be calculated by the following formula:

[0204]

[0205] Where ε0 is the dielectric constant of vacuum, usually 8.854×10 -12 F / cm; ε is the relative dielectric constant of the perovskite layer, usually in the range of 6-70, and is taken as 50 here; L is the thickness of the perovskite layer, in m; e is the electron charge, usually 1.6×10 -19 C.

[0206] Defect state density difference = (carrier defect density before passivation - carrier defect density after passivation) / carrier defect density before passivation.

[0207] 5. Place the prepared perovskite solar cell device under a light source with an intensity P of 100 mW / cm 2 Under the AM1.5G standard simulated sunlight, by changing the bias voltage on the battery device, the current value of the battery device is obtained, thereby drawing the current (Curent)-voltage (V) curve of the battery component, and thus obtaining the open circuit voltage Voc (V) and short circuit current density Jsc (mA / cm 2 ), fill factor FF (%), photoelectric conversion efficiency of battery devices, that is, battery efficiency PCE (%). Battery device effective area 0.06mm 2 The V and J of a battery device change with changes in the external load. When the external load is short-circuited, V = 0, and the current at this time is called the short-circuit current. When the external load is disconnected, the current is 0, and V at this time is called the open-circuit voltage (Voc). The output power of a battery device has a maximum value, called the maximum power point (Pmax). The fill factor (FF) of a battery device is Pmax / (Jsc × Voc). The test results are shown in Table 2.

[0208] Figure 3(a) is a deep-section three-dimensional element distribution diagram of the perovskite solar cell of comparative example 2.

[0209] Figure 3 (b) is a deep-section three-dimensional element distribution diagram of the perovskite solar cell of Example 1.

[0210] Figure 3 (a) shows the single interface passivated perovskite solar cell prepared in Comparative Example 2. The Me-pPhPACz layer is deposited before the perovskite layer is formed. The characteristic phosphonic acid functional groups are mainly distributed at the bottom interface of the perovskite layer. Figure 3 In the double-interface passivated perovskite solar cell prepared in Example 1 in (b), after the anti-solvent double-interface passivated perovskite film is crystallized, the passivation material is mainly concentrated at the bottom interface (first passivation layer) and the top interface (second passivation layer) of the perovskite layer, thereby achieving a double-interface passivation effect.

[0211] Figure 4 (a) is a deep-section element distribution curve of the perovskite solar cell of Comparative Example 2;

[0212] Figure 4 (b) is a deep-section element distribution curve of the perovskite solar cell of Example 1.

[0213] from Figure 4 As can be seen, the characteristic functional group PO3 unique to Me-pPhPACz molecules - With the signal intensity of the deep profiling process, Me-pPhPACz showed a relatively concentrated distribution at the ITO / perovskite interface, regardless of bottom interface passivation or double interface passivation. The difference is that a strong PO3 - The signal intensity is 5-10 times that of the bottom single interface passivation, proving that in the double interface passivation, Me-pPhPACz is distributed on both the upper and lower surfaces of the perovskite layer. - It has a strong bonding ability with the perovskite layer, passivating the point defects and position defects at the perovskite interface, thereby achieving passivation of the upper and lower interfaces of the perovskite layer, enabling perovskite solar cells to achieve a photoelectric conversion efficiency of more than 22%.

[0214] Table 1

[0215]

[0216] Table 2

[0217]

[0218]

[0219] As can be seen from Table 1-2, compared with the comparative example, the mass percentage of the elements in the perovskite layer in the first passivation layer and the second passivation layer of the perovskite solar cell provided by the present invention is ≥88%. The interaction of these elements can effectively fill the interface defects of the perovskite layer, reduce the formation of non-radiative recombination centers, and achieve effective passivation of the upper and lower interfaces of the perovskite layer, thereby significantly improving the photoelectric conversion efficiency of the battery.

[0220] Compared with Example 5, the concentration of the passivation material of Examples 1-4 in the anti-solvent solution is 0.2 mg / mL-5 mg / mL, so that the mass percentage of the elements in the perovskite layer in the first passivation layer is 90%-95%, and the mass percentage of the elements in the perovskite layer in the second passivation layer is 95%-99%, which can further improve the photoelectric conversion efficiency of the perovskite solar cell.

[0221] Compared with Examples 6-7, the thickness of the perovskite layer in Example 1 is between 500 nm and 700 nm, which can further improve the photoelectric conversion efficiency of the perovskite solar cell.

[0222] The perovskite solar cell of Example 1 forms a first passivation layer on one side of the perovskite layer and a second passivation layer on the other side of the perovskite layer while forming the perovskite layer. Compared with Comparative Example 4 in which the first passivation layer, the perovskite layer, and the second passivation layer are separately formed, the perovskite solar cell prepared in Example 1 has a higher photoelectric conversion efficiency.

[0223] Finally, it should be noted that those skilled in the art will readily identify other embodiments of the present invention after considering the specification and practicing the invention disclosed herein. The present invention is intended to cover any variations, uses, or adaptations of the present invention that follow the general principles of the present invention and include common knowledge or customary techniques in the art not disclosed herein. The present invention is not limited to the precise structure described above and illustrated in the accompanying drawings, and various modifications and variations may be made without departing from the scope thereof. The scope of the present invention is limited solely by the appended claims.

Claims

1. A perovskite solar cell, characterized in that A perovskite layer, a first passivation layer located on one side of the perovskite layer, and a second passivation layer located on the other side of the perovskite layer; the first passivation layer and the second passivation layer each independently include elements in the perovskite layer; The mass percentage of the elements in the perovskite layer in the first passivation layer is ≥88%; The mass percentage of the elements in the perovskite layer in the second passivation layer is ≥88%.

2. The perovskite solar cell according to claim 1, characterized in that The mass percentage of the elements in the perovskite layer in the first passivation layer is 90%-95%; And / or, the mass percentage of the elements in the perovskite layer in the second passivation layer is 95%-99%.

3. The perovskite solar cell according to claim 1 or 2, characterized in that The perovskite layer includes a perovskite material having a chemical composition of ABX3, wherein A includes at least one of methylamine ions, formamidine ions, and cesium ions, B includes lead ions and / or tin ions, and X includes at least one of iodide ions, bromide ions, and chloride ions; The elements in the perovskite layer include element A, element B and element X.

4. The perovskite solar cell according to any one of claims 1 to 3, characterized in that The first passivation layer and the second passivation layer each independently include phosphonic acid groups; The ratio of the concentration of the phosphonic acid groups in the first passivation layer to the concentration of the second passivation layer is (3-10):

1.

5. The perovskite solar cell according to claim 4, characterized in that In the deep-section element distribution curve of the perovskite solar cell, the relative intensity of the phosphine group in the first passivation layer is 3×10 -3 au-5×10 -2 au; And / or, the relative intensity of the phosphonic acid groups in the second passivation layer is 5×10 -4 au-5×10 -3 au.

6. The perovskite solar cell according to any one of claims 1 to 5, characterized in that: The difference in defect state density of the perovskite solar cell before and after passivation is 50%-85%.

7. The perovskite solar cell according to any one of claims 1 to 6, characterized in that: The ratio of the thickness of the first passivation layer to the thickness of the second passivation layer is (10-100):

1.

8. The perovskite solar cell according to any one of claims 1 to 7, characterized in that: The thickness of the first passivation layer is 50nm-100nm; And / or, the thickness of the second passivation layer is 1 nm-5 nm.

9. The perovskite solar cell according to any one of claims 1 to 8, characterized in that: The passivation material in the first passivation layer and the second passivation layer is the same.

10. The perovskite solar cell according to claim 9, characterized in that The passivation material includes a hydrophilic functional group and a hydrophobic functional group; Preferably, the hydrophilic functional group includes at least one of a phosphonic acid group, a hydroxyl group, a carboxyl group, an amino group, a sulfonic acid group, and a silane group; And / or, the hydrophobic functional group includes at least one of a substituted or unsubstituted alkyl group and a substituted or unsubstituted aromatic group.

11. The perovskite solar cell according to claim 9 or 10, characterized in that The passivation material in the first passivation layer includes at least one of 4-(3,6-dimethyl-9-hydrogen-carbazole-9-yl)phenyl)phosphonic acid, 4-(3,6-dimethoxy-9-hydrogen-carbazole-9-yl)phenyl)phosphonic acid, [4-(2,7-dibromo-9,9-dimethylacridin-10(9-hydrogen)-yl)butyl]phosphonic acid, (2-(9H-carbazole-9-yl)ethyl)phosphonic acid, 2,3,4,5,6-pentafluorobenzylphosphonic acid, [2-(3,6-diphenyl-9-hydrogen-carbazole-9-yl)ethyl]phosphonic acid, [4-(3,6-dibromo-9-hydrogen-carbazole-9-yl)butyl]phosphonic acid, and [2-(3,6-dibromo-9-hydrogen-carbazole-9-yl)ethyl]phosphonic acid; And / or, the passivation material in the second passivation layer includes at least one of 4-(3,6-dimethyl-9-hydrogen-carbazole-9-yl)phenyl)phosphonic acid, 4-(3,6-dimethoxy-9-hydrogen-carbazole-9-yl)phenyl)phosphonic acid, [4-(2,7-dibromo-9,9-dimethylacridine-10(9-hydrogen)-yl)butyl]phosphonic acid, (2-(9H-carbazole-9-yl)ethyl)phosphonic acid, 2,3,4,5,6-pentafluorobenzylphosphonic acid, [2-(3,6-diphenyl-9-hydrogen-carbazole-9-yl)ethyl]phosphonic acid, [4-(3,6-dibromo-9-hydrogen-carbazole-9-yl)butyl]phosphonic acid, and [2-(3,6-dibromo-9-hydrogen-carbazole-9-yl)ethyl]phosphonic acid.

12. The perovskite solar cell according to any one of claims 1 to 11, characterized in that: The thickness of the perovskite layer is 400nm-800nm, preferably 500nm-700nm.

13. The perovskite solar cell according to any one of claims 1 to 12, characterized in that: The perovskite solar cell also includes a hole transport layer located on the side of the first passivation layer facing away from the perovskite layer, a first electrode located on the side of the hole transport layer facing away from the perovskite layer, and an electron transport layer, a hole blocking layer and a second electrode located in sequence on the side of the second passivation layer facing away from the hole transport layer.

14. The perovskite solar cell according to claim 13, characterized in that The thickness of the hole transport layer is 20nm-50nm; and / or the hole transport layer comprises at least one of nitrogen oxide, poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine], [2-(3,6-dimethoxy-9H-carbazol-9-yl)ethyl]phosphonic acid, [2-(9H-carbazol-9-yl)ethyl]phosphonic acid, [4-(3,6-dimethyl-9H-carbazol-9-yl)butyl]phosphonic acid, and [4-(9H-carbazol-9-yl)butyl]phosphonic acid; And / or, the first electrode includes at least one of indium tin oxide, fluorine-doped tin oxide, and aluminum-doped zinc oxide; and / or, the electron transport layer comprises at least one of [6,6]-phenyl-C61-butyric acid methyl ester, fullerene, and tin dioxide; and / or, the hole blocking layer comprises at least one of 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline, titanium oxide, and zinc oxide; And / or, the second electrode includes at least one of gold, silver, copper, aluminum, a carbon electrode, indium tin oxide, and indium zinc oxide.

15. A method for preparing a perovskite solar cell according to any one of claims 1 to 14, characterized in that: The following steps are involved: While forming the perovskite layer, the first passivation layer is formed on one side of the perovskite layer, and the second passivation layer is formed on the other side of the perovskite layer to obtain the perovskite solar cell.

16. The method for preparing a perovskite solar cell according to claim 15, wherein: The step of forming the perovskite layer while forming the first passivation layer on one side of the perovskite layer and forming the second passivation layer on the other side of the perovskite layer to obtain the perovskite solar cell comprises: A perovskite precursor solution is coated on the hole transport layer, and an anti-solvent solution containing a passivation material is added to the perovskite precursor solution during the coating process.

17. The method for preparing a perovskite solar cell according to claim 16, wherein: Adding an antisolvent solution containing a passivation material to the perovskite precursor solution during the coating process comprises: 5s-10s before the end of coating, an anti-solvent solution containing a passivation material is added to the perovskite precursor solution.

18. The method for preparing a perovskite solar cell according to claim 16 or 17, wherein: The anti-solvent includes at least one of ethanol, isopropanol, toluene, chlorobenzene, chloroform, ethyl acetate, dimethylformamide, dimethyl sulfoxide and the like; And / or, the concentration of the passivation material in the anti-solvent solution is 0.01 mg / mL-10 mg / mL, preferably 0.2 mg / mL-5 mg / mL.

19. The method for preparing a perovskite solar cell according to any one of claims 15 to 18, wherein: Also includes: An electron transport layer, a hole blocking layer and a second electrode are sequentially formed on the second passivation layer.

20. A stacked battery, characterized in that: A perovskite solar cell comprising the perovskite solar cell according to any one of claims 1 to 14, or a perovskite solar cell prepared according to the method for preparing a perovskite solar cell according to any one of claims 15 to 19.

21. A photovoltaic module, characterized in that: The invention comprises the perovskite solar cell according to any one of claims 1 to 14, or the perovskite solar cell prepared according to the method for preparing a perovskite solar cell according to any one of claims 15 to 19, or the stacked cell according to claim 20.

22. An electrical device, characterized in that: A photovoltaic module comprising the photovoltaic module according to claim 21.

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