A perovskite solar cell and its preparation method

Abstract

The present invention provides a perovskite solar cell and a preparation method thereof. The preparation method of the perovskite solar cell includes: providing a substrate; forming a first electrode layer on one surface of the substrate; forming a first carrier transport layer on the surface of the first electrode layer facing away from the substrate; forming an organic amine salt layer on the surface of the first carrier transport layer facing away from the substrate; forming a metal halide salt layer on the surface of the organic amine salt layer facing away from the substrate using a dry process, forming an organic liquid film on the surface of the metal halide salt layer facing away from the substrate, performing a first annealing on the organic liquid film, reacting the organic liquid film with the metal halide salt layer to form a light absorption layer, and reacting the organic amine salt layer with the light absorption layer to form a first passivation layer, the first passivation layer being located on one surface of the light absorption layer, and having a band gap greater than the band gap of the light absorption layer. The formation of the first passivation layer can improve the photoelectric conversion performance and structural stability of the perovskite solar cell.

Description

Technical Field

[0001] The present invention relates to the technical field of solar cells, and in particular to a perovskite solar cell and a preparation method thereof. Background Art

[0002] In recent years, organic-inorganic hybrid perovskite materials have attracted widespread attention due to their excellent optoelectronic properties. In just over a decade, the efficiency of perovskite solar cells has increased from 3.8% to 25.8%, showing great potential.

[0003] As the light-absorbing layer in perovskite solar cells, the preparation methods of perovskite thin films include one-step and two-step methods. The two-step method first forms a solid metal halide layer on the surface of the first carrier transport layer, then forms an organic liquid film on the surface of the metal halide layer, and finally anneals the perovskite film. However, due to the lattice mismatch between the perovskite material and the metal halide, the stress caused by the lattice expansion during the annealing process can damage the first carrier transport layer, thereby affecting the first carrier transport capacity of the first carrier transport layer and, in turn, the photoelectric conversion performance of the perovskite solar cell. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is how to improve the photoelectric conversion performance of perovskite solar cells, thereby providing a perovskite solar cell and a preparation method thereof.

[0005] The present invention provides a method for preparing a perovskite solar cell, comprising: providing a substrate; forming a first electrode layer on one side surface of the substrate; forming a first carrier transport layer on a side surface of the first electrode layer facing away from the substrate; forming an organic amine salt layer on a side surface of the first carrier transport layer facing away from the substrate; forming a metal halide salt layer on a side surface of the organic amine salt layer facing away from the substrate using a dry process, forming an organic liquid film on a side surface of the metal halide salt layer facing away from the substrate, performing a first annealing on the organic liquid film, reacting the organic liquid film with the metal halide salt layer to generate a light absorption layer, reacting the organic amine salt layer with the light absorption layer to generate a first passivation layer, wherein the first passivation layer is located on one side surface of the light absorption layer, the material of the light absorption layer is a three-dimensional perovskite material, the material of the first passivation layer is a two-dimensional perovskite material, and the band gap of the first passivation layer is greater than the band gap of the light absorption layer.

[0006] Optionally, the material of the organic amine salt layer includes at least one of tetrabutylammonium bromide, tetrabutylammonium iodide, dimethylammonium iodide, triethylammonium iodide, phenethylammonium iodide, p-fluorophenethylammonium iodide, phenethylammonium bromide, butylammonium bromide, isopropylammonium bromide, octylammonium iodide, tetrafluorobenzylammonium iodide, tribromophenethylammonium iodide, phenpropylammonium iodide and tetrafluorophenethylammonium bromide.

[0007] Optionally, the step of forming an organic amine salt layer on the surface of the first carrier transport layer facing away from the substrate includes: preparing a first organic amine salt solution, forming a first organic amine salt liquid film on the surface of the first carrier transport layer facing away from the substrate, and performing a second annealing on the first organic amine salt liquid film to obtain the organic amine salt layer; or, forming the organic amine salt layer on the surface of the first carrier transport layer facing away from the substrate using a vacuum evaporation process.

[0008] Optionally, the process of forming the first organic amine salt liquid film includes a slit coating process, a doctor blade coating process, a spray coating process, a spin coating process or an immersion process.

[0009] Optionally, the concentration of the solute in the first organic amine salt solution is 0.005 mol / L-1 mol / L, and the solvent of the first organic amine salt solution includes at least one of dimethylamide, dimethyl sulfoxide, N-methylpyrrolidone, ethanol, methanol, and isopropanol.

[0010] Optionally, the temperature of the second annealing is 50° C.-120° C., and the time of the second annealing is 5 min-30 min.

[0011] Optionally, the dry process includes a vacuum evaporation process, a magnetron sputtering process, a chemical vapor deposition process, an atomic deposition process or a reactive plasma deposition process; the process of forming an organic liquid film on the surface of the metal halide layer facing away from the substrate includes a slit coating process, a scraping process, a spraying process, a spin coating process or an immersion process; during the process of forming the organic liquid film and the first annealing process, the substrate is in a nitrogen atmosphere or an inert atmosphere.

[0012] Optionally, the deposition rate of the metal halide salt layer is 0.5Å / s-50Å / s.

[0013] Optionally, the concentration of the organic liquid membrane is 0.2 mol / L-1 mol / L.

[0014] Optionally, the thickness of the organic amine salt layer is 1 nm-100 nm; the thickness of the metal halide salt layer is 10 nm-2000 nm.

[0015] Optionally, the thickness of the organic amine salt layer is 5 nm-20 nm; the thickness of the metal halide salt layer is 100 nm-1000 nm.

[0016] Optionally, it also includes: after forming the light absorbing layer, forming a second passivation layer on the surface of the light absorbing layer facing away from the substrate, the material of the second passivation layer is a two-dimensional perovskite material, and the band gap of the second passivation layer is greater than the band gap of the light absorbing layer; forming a second carrier transport layer on the surface of the second passivation layer facing away from the light absorbing layer.

[0017] Optionally, the step of forming a second passivation layer on the surface of the light absorbing layer facing away from the substrate includes: preparing a second organic amine salt solution, forming a second organic amine salt liquid film on the surface of the light absorbing layer facing away from the substrate, and performing a third annealing on the second organic amine salt liquid film to convert the second organic amine salt liquid film into a second passivation layer.

[0018] Optionally, the process for forming the second organic amine salt liquid film includes a slit coating process, a doctor blade coating process, a spray coating process or a spin coating process.

[0019] Optionally, the concentration of the solute in the second organic amine salt solution is 0.005 mol / L-1 mol / L, and the solvent of the second organic amine salt solution includes at least one of dimethylamide, dimethyl sulfoxide, N-methylpyrrolidone, ethanol, methanol and isopropanol.

[0020] Optionally, the material of the solute in the second organic amine salt solution includes at least one of tetrabutylammonium bromide, tetrabutylammonium iodide, dimethylammonium iodide, triethylammonium iodide, phenethylammonium iodide, p-fluorophenethylammonium iodide, phenethylammonium bromide, butylammonium bromide, isopropylammonium bromide, octylammonium iodide, tetrafluorobenzylammonium iodide, tribromophenethylammonium iodide, phenpropylammonium iodide and tetrafluorophenethylammonium bromide.

[0021] Optionally, the temperature of the third annealing is 50° C.-120° C., and the time of the third annealing is 5 min-30 min.

[0022] The present invention also provides a perovskite solar cell, comprising: a substrate; a first electrode layer located on one side surface of the substrate; a first carrier transport layer located on a side surface of the first electrode layer facing away from the substrate;

[0023] A first passivation layer located on a surface of the first carrier transport layer facing away from the substrate, wherein the material of the first passivation layer is a two-dimensional perovskite material; and a light absorption layer located on a surface of the first passivation layer facing away from the substrate, wherein the material of the light absorption layer is a three-dimensional perovskite material, and the band gap of the first passivation layer is greater than the band gap of the light absorption layer.

[0024] Optionally, the difference between the band gap of the first passivation layer and the band gap of the light absorbing layer is 0.5 eV-1.5 eV.

[0025] Optionally, the material of the first passivation layer includes M2A n-1 B n X 3n+1 , M includes: at least one of tetrabutylamine cation, dimethylamine cation, triethylamine cation, phenethylamine cation, p-fluorophenethylamine cation, butylamine cation, isopropylamine cation, octylamine cation, tetrafluorobenzylamine cation, tribromophenethylamine cation and phenylpropylamine cation, A includes at least one of methylamino group, formamidine group and cesium ion, B includes lead ion and tin ion son At least one of the following, X is a halogen anion, and the value of n is 2-6.

[0026] Optionally, the thickness of the first passivation layer is 1 nm-30 nm; the thickness of the light absorption layer is 300 nm-1200 nm.

[0027] Optionally, it also includes: a second passivation layer located on the surface of the side of the light absorbing layer away from the substrate, the material of the second passivation layer is a two-dimensional perovskite material, and the band gap of the second passivation layer is greater than the band gap of the light absorbing layer; and a second carrier transport layer located on the surface of the side of the second passivation layer away from the light absorbing layer.

[0028] Optionally, the difference between the band gap of the second passivation layer and the band gap of the light absorbing layer is 0.5 eV-1.5 eV.

[0029] Optionally, the material of the second passivation layer includes M2A n-1 B n X 3n+1 , M includes: at least one of tetrabutylamine cation, dimethylamine cation, triethylamine cation, phenethylamine cation, p-fluorophenethylamine cation, butylamine cation, isopropylamine cation, octylamine cation, tetrafluorobenzylamine cation, tribromophenethylamine cation and phenylpropylamine cation, A includes at least one of methylamino group, formamidine group and cesium ion, B includes lead ion and tin ion son At least one of the following, X is a halogen anion, and the value of n is 2-6.

[0030] Optionally, the thickness of the second passivation layer is 1 nm-30 nm; the thickness of the light absorption layer is 300 nm-1200 nm.

[0031] The technical solution of the present invention has the following advantages:

[0032] 1. The preparation method of the perovskite solar cell provided by the present invention forms an organic amine salt layer on the surface of the first carrier transport layer, so that after the metal halide layer deposited on the surface of the organic amine salt layer reacts with the organic liquid film to form a light absorption layer, the light absorption layer reacts with the organic amine salt layer to form a first passivation layer. The organic amine salt layer can buffer the stress caused by lattice expansion during the formation of the light absorption layer, thereby avoiding damage to the first carrier transport layer; the formation of the first passivation layer also reduces the amount of residual metal halide salt between the light absorption layer and the first carrier transport layer, thereby passivating the interface defects between the light absorption layer and the first carrier transport layer; at the same time, the material of the first passivation layer is a two-dimensional perovskite material, the material of the light absorption layer is a three-dimensional perovskite material, and the band gap of the first passivation layer is greater than the band gap of the light absorption layer, that is, a high-low junction structure is formed at the interface between the first passivation layer and the light absorption layer, which is beneficial to the transport effect of the first carrier generated by the light absorption layer to the first carrier transport layer; in summary, the formation of the above-mentioned first passivation layer can improve the photoelectric conversion performance of the perovskite solar cell;

[0033] In addition, two-dimensional perovskite materials have excellent structural stability and photostability. Therefore, the presence of the first passivation layer can also improve the structural stability of perovskite solar cells.

[0034] 2. The preparation method of the perovskite solar cell provided by the present invention comprises a second passivation layer formed between the light absorbing layer and the second carrier transport layer. The formation of the second passivation layer reduces the amount of residual metal halide salts between the light absorbing layer and the second carrier transport layer, thereby passivating the interface defects between the light absorbing layer and the second carrier transport layer. The material of the second passivation layer is a two-dimensional perovskite material, and the band gap of the second passivation layer is larger than the band gap of the light absorbing layer. That is, a high-low junction structure is formed at the interface between the second passivation layer and the light absorbing layer, which is beneficial to the transport effect of the second carriers generated by the light absorbing layer to the second carrier transport layer. In summary, the formation of the second passivation layer can further improve the photoelectric conversion performance of the perovskite solar cell.

[0035] In addition, two-dimensional perovskite materials have excellent structural stability and photostability. Therefore, the presence of the second passivation layer can further improve the structural stability of perovskite solar cells.

[0036] 3. In the perovskite solar cell provided by the present invention, the first passivation layer located between the first carrier transport layer and the light absorption layer can prevent the first carrier transport layer from being damaged; the formation of the first passivation layer also reduces the amount of residual metal halide salts located between the light absorption layer and the first carrier transport layer, thereby passivating the interface defects between the light absorption layer and the first carrier transport layer; at the same time, the material of the first passivation layer is a two-dimensional perovskite material, the material of the light absorption layer is a three-dimensional perovskite material, and the band gap of the first passivation layer is greater than the band gap of the light absorption layer, that is, a high-low junction structure is formed at the interface between the first passivation layer and the light absorption layer, which is beneficial to the transport effect of the first carriers generated by the light absorption layer to the first carrier transport layer; in summary, the performance of the above-mentioned first passivation layer can improve the photoelectric conversion performance of the perovskite solar cell;

[0037] In addition, two-dimensional perovskite materials have excellent structural stability and photostability. Therefore, the presence of the first passivation layer can also improve the structural stability of perovskite solar cells.

[0038] 4. The perovskite solar cell provided by the present invention further includes a second passivation layer located between the light absorbing layer and the second carrier transport layer. The formation of the second passivation layer reduces the amount of residual metal halide located between the light absorbing layer and the second carrier transport layer, thereby passivating the interface defects between the light absorbing layer and the second carrier transport layer; the material of the second passivation layer is a two-dimensional perovskite material, and the band gap of the second passivation layer is larger than the band gap of the light absorbing layer; that is, a high-low junction structure is formed at the interface between the second passivation layer and the light absorbing layer, which is beneficial to the transport effect of the second carriers generated by the light absorbing layer to the second carrier transport layer; in summary, the formation of the second passivation layer can further improve the photoelectric conversion performance of the perovskite solar cell;

[0039] In addition, two-dimensional perovskite materials have excellent structural stability and photostability. Therefore, the presence of the second passivation layer can further improve the structural stability of perovskite solar cells. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0041] Figure 1 A flow chart of a method for preparing a perovskite solar cell according to an embodiment of the present invention;

[0042] Figure 2A schematic structural diagram of a perovskite solar cell prepared according to an embodiment of the present invention;

[0043] Figure 3 This is a schematic structural diagram of another perovskite solar cell prepared according to an embodiment of the present invention. DETAILED DESCRIPTION

[0044] The technical solution of the present invention is described clearly and completely below in conjunction with the accompanying drawings. Obviously, the embodiments described are 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 any creative work are within the scope of protection of the present invention. In the description of the present invention, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance.

[0045] This embodiment provides a method for preparing a perovskite solar cell. Figure 1 and Figure 2 , including the following steps:

[0046] Step S1: providing a substrate 1;

[0047] Step S2: forming a first electrode layer 2 on one side surface of the substrate 1;

[0048] Step S3: forming a first carrier transport layer 3 on a surface of the first electrode layer 2 facing away from the substrate 1;

[0049] Step S4: forming an organic amine salt layer on the surface of the first carrier transport layer 3 facing away from the substrate 1;

[0050] Step S5: using a dry process to form a metal halide salt layer on the surface of the organic amine salt layer on the side away from the substrate 1, forming an organic liquid film on the surface of the metal halide salt layer on the side away from the substrate 1, performing a first annealing on the organic liquid film, the organic liquid film reacts with the metal halide salt layer to generate a light absorption layer 5, the organic amine salt layer reacts with the absorption layer to generate a first passivation layer 4, the first passivation layer 4 is located on one side of the light absorption layer 5, the material of the light absorption layer 5 is a three-dimensional perovskite material, the material of the first passivation layer 4 is a two-dimensional perovskite material, and the band gap of the first passivation layer 4 is greater than the band gap of the light absorption layer 5.

[0051] The above-mentioned method for preparing a perovskite solar cell forms an organic amine salt layer on the surface of the first carrier transport layer 3, so that the metal halide salt layer deposited on the surface of the organic amine salt layer reacts with the organic liquid film to form a light absorption layer 5, and then the light absorption layer reacts with the organic amine salt layer to form a first passivation layer 4. The formation of the organic amine salt layer can buffer the stress caused by lattice expansion during the formation of the light absorption layer 5, thereby preventing the first carrier transport layer 3 from being damaged; the formation of the first passivation layer 4 also reduces the amount of residual metal halide salt between the light absorption layer 5 and the first carrier transport layer 3, thereby passivating the interface between the light absorption layer 5 and the first carrier transport layer 3 defects; at the same time, the material of the first passivation layer 4 is a two-dimensional perovskite material, and the material of the light absorption layer 5 is a three-dimensional perovskite material. The band gap of the first passivation layer 4 is larger than the band gap of the light absorption layer 5, that is, a high-low junction structure is formed at the interface between the first passivation layer 4 and the light absorption layer 5, which is beneficial to the transport effect of the first carriers generated by the light absorption layer 5 to the first carrier transport layer 3; in summary, the formation of the above-mentioned first passivation layer 4 can improve the photoelectric conversion performance of the perovskite solar cell; in addition, the two-dimensional perovskite material has excellent structural stability and light stability. Therefore, the presence of the first passivation layer 4 can also improve the structural stability of the perovskite solar cell.

[0052] The preparation method of the perovskite solar cell provided in this embodiment adopts a dry process to form the metal halide salt layer. During the process of forming the metal halide salt layer, the organic amine salt layer will not dissolve. Therefore, after the metal halide salt layer reacts with the organic liquid film to form a light absorption layer, the light absorption layer can react with the organic amine salt layer to form a first passivation layer. Moreover, by preparing the metal halide salt layer through a dry process, the thickness and uniformity of the metal halide salt layer can be better controlled, which is conducive to the preparation of a high-quality light absorption layer. In addition, the preparation method of the perovskite solar cell provided in this embodiment is easy to upgrade the existing single-layer battery equipment to develop stacked batteries. It is not only suitable for small-area laboratory devices, but also can prepare large-area single-cell perovskite solar cells and stacked perovskite solar cells.

[0053] The following combination Figure 2 Provide a clear and complete description of the fabrication methods for perovskite solar cells.

[0054] Step S1: providing a substrate 1;

[0055] Specifically, the substrate 1 includes, but is not limited to, glass, heterojunction cells, crystalline silicon cells, or thin-film solar cells. Thin-film solar cells include, but are not limited to, copper indium gallium selenide thin-film solar cells, cadmium telluride thin-film solar cells, gallium arsenide thin-film solar cells, and perovskite solar cells. Crystalline silicon cells include, but are not limited to, N-type single-crystal heterojunction cells (HJT cells). When the substrate is glass, a single-junction perovskite solar cell is ultimately produced. When the substrate is a heterojunction cell, crystalline silicon cell, or thin-film solar cell, a tandem cell is ultimately produced.

[0056] Step S2: forming a first electrode layer 2 on one side surface of the substrate 1;

[0057] Specifically, the process for forming the first electrode layer 2 on one side of the substrate 1 includes, but is not limited to, a magnetic sputtering process or a chemical vapor deposition process. The material of the first electrode layer 2 includes, but is not limited to, fluorine-doped tin oxide (FTO) or indium tin oxide (ITO). It should be understood that when the substrate is glass and the material of the first electrode layer is FTO or ITO, commercially available FTO conductive glass or ITO conductive glass can be directly used. The thickness of the material of the first electrode layer is 80 nm to 200 nm, for example, 100 nm, 150 nm, or 180 nm.

[0058] After the first electrode layer 2 is formed on one surface of the substrate 1, the sample needs to be pretreated; specifically, the pretreatment includes the following steps: ultrasonically cleaning the sample in sequence using a detergent, deionized water, ethanol, acetone, isopropanol, and ethanol, with each ultrasonic cleaning lasting 10 minutes to 20 minutes, for example, 15 minutes; then, drying the sample; then, performing ultraviolet ozone treatment on the sample, with the ultraviolet ozone treatment lasting 15 minutes to 25 minutes, for example, 20 minutes.

[0059] Step S3: forming a first carrier transport layer 3 on a surface of the first electrode layer 2 facing away from the substrate 1;

[0060] Specifically, the method of forming the first carrier transport layer 3 includes but is not limited to spin coating, scraping, spraying, vacuum evaporation, and magnetron sputtering. The preparation method can be selected according to the material of the first carrier transport layer.

[0061] Step S4: forming an organic amine salt layer on the surface of the first carrier transport layer 3 facing away from the substrate 1;

[0062] The material of the organic amine salt layer includes at least one of tetrabutylammonium bromide, tetrabutylammonium iodide, dimethylammonium iodide, triethylammonium iodide, methylammonium bromide, phenethylammonium iodide, p-fluorophenethylammonium iodide, methylammonium iodide, phenethylammonium bromide, butylammonium bromide, isopropylammonium bromide, octylammonium iodide, tetrafluorobenzylammonium iodide, tribromophenethylammonium iodide, phenpropylammonium iodide and tetrafluorophenethylammonium bromide.

[0063] In one embodiment, the thickness of the organic amine salt layer is 1 nm to 100 nm. For example, the thickness of the organic amine salt layer can be 50 nm, 55 nm, 60 nm, 65 nm, 70 nm, 75 nm, or 80 nm. Preferably, the thickness of the organic amine salt layer is 5 nm to 20 nm, for example, 8 nm, 10 nm, 12 nm, 15 nm, or 18 nm.

[0064] In one embodiment, the step of forming an organic amine salt layer on a surface of the first carrier transport layer 3 facing away from the substrate 1 includes:

[0065] Step S41: preparing a first organic amine salt solution, wherein the solvent of the first organic amine salt solution includes at least one of dimethylamide, dimethyl sulfoxide, N-methylpyrrolidone, ethanol, methanol, and isopropanol; the solute of the first organic amine salt solution is the same as the material of the organic amine salt layer; the concentration of the solute in the first organic amine salt solution is 0.005 mol / L-1 mol / L, and illustratively, the concentration of the solute in the first organic amine salt solution is 0.008 mol / L, 0.01 mol / L, 0.05 mol / L, 0.15 mol / L, 0.25 mol / L, 0.35 mol / L, 0.65 mol / L, 0.75 mol / L, 0.85 mol / L, or 0.95 mol / L;

[0066] Step S42: forming a first organic amine salt liquid film on a surface of the first carrier transport layer 3 facing away from the substrate 1, wherein the process for forming the first organic amine salt liquid film includes a slit coating process, a doctor blade process, a spray coating process, a spin coating process or an immersion process;

[0067] Step S43: performing a second annealing on the first organic amine salt liquid film to obtain the organic amine salt layer;

[0068] Specifically, the second annealing temperature is 50° C. to 120° C., and the second annealing time is 5 min to 30 min. Exemplarily, the second annealing temperature is 90° C., 100° C., or 110° C., and the second annealing time is 10 min, 15 min, or 20 min. The higher the second annealing temperature, the shorter the annealing time.

[0069] In another embodiment, the organic amine salt layer may be formed on the surface of the first carrier transport layer 3 facing away from the substrate 1 by using a vacuum evaporation process.

[0070] Step S5: forming a first passivation layer 4 and a light absorption layer 5 on a surface of the first carrier transport layer 3 facing away from the substrate 1, wherein the first passivation layer 4 is located between the light absorption layer 5 and the first carrier transport layer 3, wherein the material of the light absorption layer 5 is a three-dimensional perovskite material, and the material of the first passivation layer 4 is a two-dimensional perovskite material, and the band gap of the first passivation layer 4 is larger than the band gap of the light absorption layer 5;

[0071] Specifically, the step of forming the first passivation layer 4 and the light absorption layer 5 on the surface of the first carrier transport layer 3 facing away from the substrate 1 includes:

[0072] Step S51: forming a metal halide salt layer on a surface of the organic amine salt layer facing away from the substrate 1 using a dry process;

[0073] Specifically, the dry process includes a vacuum evaporation process, a magnetron sputtering process, a chemical vapor deposition process, an atomic deposition process or a reactive plasma deposition process; the deposition rate of the metal halide layer is 0.5Å / s-50Å / s; exemplarily, the deposition rate of the metal halide layer can be 10Å / s, 15Å / s, 20Å / s, 25Å / s or 30Å / s.

[0074] The material of the metal halide layer includes at least one of lead iodide, cesium iodide, lead bromide, cesium bromide, lead chloride and cesium chloride; the thickness of the metal halide layer is 10nm-2000nm; illustratively, the thickness of the metal halide layer can be 100nm, 200nm, 300nm, 400nm, 500nm, 600nm, 700nm, 800nm, 900nm, 1000nm, 1500nm or 2000nm; preferably, the thickness of the metal halide layer is 100nm-1000nm.

[0075] Step S52: forming an organic liquid film on the surface of the metal halide layer facing away from the substrate 1;

[0076] Specifically, the process of forming the organic liquid film on the surface of the metal halide layer facing away from the substrate 1 includes a slit coating process, a doctor blade coating process, a spray coating process, a spin coating process or an immersion process; during the process of forming the organic liquid film, the substrate is in a nitrogen atmosphere or an inert atmosphere.

[0077] In the organic solution used to form the organic liquid membrane, the solute includes at least one of benzylammonium bromide, methylammonium iodide, butylammonium acetate, methylammonium bromide, methylammonium bromide, phenethylammonium chloride, methylammonium iodide, methylbutyric acid ammonium, potassium ammonium chloride, ethylammonium iodide, phenylbutylammonium bromide, phenylethylammonium bromide, phenylpropylammonium iodide, methylammonium chloride, methylammonium chloride, and methylammonium bromide; the solvent includes at least one of ethanol, methanol, and isopropanol, and the solvent may also include other alcohol solutions that have excellent solubility for the organic liquid membrane but are insoluble in the metal halide layer; the solute concentration is 0.2 mol / L-1 mol / L, for example, 0.8 mol / L, and the solute concentration of the organic solution required for different processes is different.

[0078] Step S53: performing a first annealing on the organic liquid film, wherein the organic liquid film reacts with a partial thickness of the metal halide salt layer to form a light absorbing layer 5, and the organic amine salt layer reacts with a partial thickness of the metal halide salt layer to form a first passivation layer 4, wherein the first passivation layer 4 is located on one side surface of the light absorbing layer 5;

[0079] Specifically, during the first annealing process, the substrate 1 is in a nitrogen atmosphere or an inert atmosphere. The temperature of the first annealing is 80° C. to 170° C., and the first annealing time is 5 min to 30 min. Exemplarily, the first annealing temperature is 90° C., 100° C., or 150° C., and the first annealing time is 10 min, 20 min, or 25 min. The higher the first annealing temperature, the shorter the first annealing time.

[0080] The thickness of the first passivation layer 4 is 1 nm-30 nm. For example, the thickness of the first passivation layer 4 is 10 nm, 15 nm or 20 nm.

[0081] The thickness of the light absorbing layer 5 is 300 nm-1200 nm. For example, the thickness of the light absorbing layer 5 is 400 nm, 500 nm, 800 nm or 1000 nm.

[0082] Step S6: forming a second carrier transport layer 6 on a surface of the light absorbing layer 5 facing away from the substrate 1;

[0083] Specifically, the method of forming the second carrier transport layer 6 includes but is not limited to spin coating, blade coating, spray coating, vacuum evaporation, and magnetron sputtering. The preparation method can be selected according to the material of the second carrier transport layer.

[0084] It should be understood that one of the first carrier transport layer 3 and the second carrier transport layer 6 is a hole transport layer, and the other is an electron transport layer; when the first carrier transport layer is a hole transport layer and the second carrier transport layer is an electron transport layer, the perovskite cell is an inverted perovskite solar cell; when the first carrier transport layer is an electron transport layer and the second carrier transport layer is a hole transport layer, the perovskite cell is a formal perovskite solar cell.

[0085] The materials of the hole transport layer include but are not limited to NiO x , CuSCN, Cu2O or CuI; the thickness of the hole transport layer is 5nm-50nm; illustratively, the thickness of the hole transport layer can be 10nm, 15nm, 20nm or 30nm.

[0086] Materials for the electron transport layer include but are not limited to titanium dioxide, tin dioxide, zinc oxide, fullerene C70, fullerene C60, [6,6]-phenyl-C71-butyric acid methyl ester (PC 71 BM), [6,6]-phenyl-C61-butyric acid methyl ester (PC 61 BM). The thickness of the electron transport layer is 10 nm to 40 nm. For example, the thickness of the electron transport layer can be 15 nm, 20 nm, 25 nm or 30 nm.

[0087] Step S7: forming a second electrode layer 7 on the side of the second carrier transport layer 6 facing away from the substrate 1, to obtain Figure 2 The perovskite solar cell shown.

[0088] Specifically, the method for forming the second electrode layer 7 includes, but is not limited to, vacuum evaporation. The material of the second electrode layer includes, but is not limited to, gold, silver, and copper. The thickness of the second electrode layer is 80 nm to 100 nm. Exemplarily, the thickness of the second electrode layer can be 80 nm, 82 nm, 85 nm, 87 nm, 90 nm, 95 nm, or 100 nm.

[0089] When the first carrier transport layer is a hole transport layer and the second carrier transport layer is an electron transport layer, the method further includes: forming a hole blocking layer (not shown in the figure) on the surface of the second carrier transport layer 6 facing away from the light absorption layer 5; the second electrode layer 7 is located on the surface of the hole blocking layer facing away from the light absorption layer 5; the hole blocking layer is suitable for preventing recombination of electrons and holes, and the hole blocking layer includes but is not limited to BCP (bathocuproine).

[0090] As a preferred embodiment, see Figure 3The method for preparing a perovskite solar cell further includes: after forming the light absorbing layer 5, forming a second passivation layer 8 on a surface of the light absorbing layer 5 facing away from the substrate 1. The material of the second passivation layer 8 is a two-dimensional perovskite material, and the band gap of the second passivation layer 8 is larger than the band gap of the light absorbing layer 5; and forming a second carrier transport layer 6 on a surface of the second passivation layer 8 facing away from the light absorbing layer 5. The formation of the second passivation layer reduces the amount of residual metal halide between the light absorbing layer and the second carrier transport layer, thereby passivating the interface defects between the light absorbing layer and the second carrier transport layer. At the same time, a high-low junction structure is formed at the interface between the second passivation layer 8 and the light absorbing layer 5, which facilitates the transport of second carriers generated by the light absorbing layer 5 to the second carrier transport layer 6. In summary, the formation of the second passivation layer can further improve the photoelectric conversion performance of the perovskite solar cell. In addition, two-dimensional perovskite materials have excellent structural stability and photostability. Therefore, the presence of the second passivation layer can further improve the structural stability of the perovskite solar cell. The first passivation layer and the second passivation layer formed simultaneously can effectively inhibit charge recombination and promote charge transfer, thereby effectively reducing the turn-on voltage loss of the perovskite solar cell.

[0091] Specifically, the step of forming the second passivation layer 8 on the surface of the light absorbing layer 5 facing away from the substrate 1 includes:

[0092] A second organic amine salt solution is prepared, wherein the solute material in the second organic amine salt solution includes at least one of tetrabutylammonium bromide, tetrabutylammonium iodide, dimethylammonium iodide, triethylammonium iodide, methylammonium bromide, phenethylammonium iodide, p-fluorophenethylammonium iodide, methylammonium iodide, phenethylammonium bromide, butylammonium bromide, isopropylammonium bromide, octylammonium iodide, tetrafluorobenzylammonium iodide, tribromophenethylammonium iodide, phenylpropylammonium iodide and tetrafluorophenethylammonium bromide; and the solvent of the second organic amine salt solution includes dimethylamine bromide, triethylammonium iodide, phenylpropylammonium iodide and tetrafluorophenethylammonium bromide. At least one of methylamide, dimethyl sulfoxide, N-methylpyrrolidone, ethanol, methanol and isopropanol; the concentration of the solute in the second organic amine salt solution is 0.005 mol / L-1 mol / L, exemplarily, the concentration of the solute in the second organic amine salt solution is 0.15 mol / L, 0.25 mol / L, 0.35 mol / L, 0.65 mol / L, 0.75 mol / L, 0.85 mol / L or 0.95 mol / L.

[0093] forming a second organic amine salt liquid film on a surface of the light absorbing layer 5 facing away from the substrate 1; the process of forming the second organic amine salt liquid film includes a slit coating process, a doctor blade coating process, a spray coating process or a spin coating process;

[0094] The second organic amine salt liquid film is subjected to a third annealing, and the second organic amine salt liquid film reacts with residual metal halide on a surface of the light absorbing layer facing away from the substrate to form a second passivation layer.

[0095] Specifically, the temperature of the third annealing is 50°C-120°C, and the time of the third annealing is 5 min-30 min; illustratively, the temperature of the second annealing is 90°C, 100°C or 110°C, and the time of the third annealing is 10 min, 15 min or 20 min. The higher the temperature of the third annealing, the shorter the time of the third annealing.

[0096] The thickness of the second passivation layer is 1 nm-30 nm. Exemplarily, the thickness of the second passivation layer is 5 nm, 10 nm, 15 nm or 20 nm.

[0097] refer to Figure 2 This embodiment further provides a perovskite solar cell, comprising:

[0098] Substrate 1;

[0099] a first electrode layer 2 located on one side surface of the substrate 1;

[0100] a first carrier transport layer 3 located on a surface of the first electrode layer 2 facing away from the substrate 1;

[0101] a first passivation layer 4 located on a surface of the first carrier transport layer 3 facing away from the substrate 1, wherein the material of the first passivation layer 4 is a two-dimensional perovskite material;

[0102] a light absorbing layer 5 located on a surface of the first passivation layer 4 facing away from the substrate 1 , wherein the light absorbing layer 5 is made of a three-dimensional perovskite material, and the band gap of the first passivation layer 4 is larger than the band gap of the light absorbing layer 5 ;

[0103] a second carrier transport layer 6 located on a surface of the light absorbing layer 5 facing away from the substrate 1;

[0104] A second electrode layer 7 is located on a side of the second carrier transport layer 6 facing away from the substrate 1 .

[0105] In the above-mentioned perovskite solar cell, the first passivation layer 4 located between the first carrier transport layer 3 and the light absorption layer 5 can buffer the stress caused by the lattice expansion during the formation of the light absorption layer 5, thereby avoiding damage to the first carrier transport layer 3; the formation of the first passivation layer 4 also reduces the amount of residual metal halide salts between the light absorption layer and the first carrier transport layer, thereby passivating the interface defects between the light absorption layer 5 and the first carrier transport layer 3; at the same time, a high-low junction structure is formed at the interface between the first passivation layer 4 and the light absorption layer 5, which is beneficial to the transport effect of the first carriers generated by the light absorption layer 5 to the first carrier transport layer 3; in summary, the performance of the first passivation layer 4 can improve the photoelectric conversion performance of the perovskite solar cell; in addition, the two-dimensional perovskite material has excellent structural stability and light stability, therefore, the presence of the first passivation layer 4 can also improve the structural stability of the perovskite solar cell.

[0106] Specifically, the difference between the band gap of the first passivation layer 4 and the band gap of the light absorption layer 5 is 0.5ev-1.5eV, for example, 1.0eV; if the difference between the band gap of the first passivation layer and the band gap of the light absorption layer is less than xx, the degree of forming a high-low junction at the interface between the first passivation layer and the light absorption layer is small, the passivation effect on the light absorption layer is small, and the effect of enhancing the extraction and transport of carriers is not obvious.

[0107] Furthermore, the material of the first passivation layer 4 includes M2A n-1 B n X 3n+1 , M includes: tetrabutylammonium cation (TBA + ), dimethylamine cation (DMA + ), triethylamine cation (TEA + ), phenylethylamine cation (PEA + ), p-fluorophenethylamine cation (pF-PEA + ), butylamine cation (BA + ), isopropylamine cation (2-PA + ), octylamine cation (OA + ), tetrafluorobenzylamine cation (p-FPMA + ), tribromophenethylamine cation (3-Br-PEA + ) and phenylpropylamine cation (PPA + ), A includes a methylamino group (MA + ), formamidine group (FA + ) and cesium ions (Cs + ), B includes lead ions (Pb 2+ ) and tin son( Sn 2+） At least one of the following, X is a halogen anion, and n is 2-6; the general structural formula of the three-dimensional perovskite is ABX3, A is a monovalent cation, B is a divalent cation, and X is a halogen anion, wherein A includes but is not limited to a methylamino group (MA + ), formamidine group (FA + ) or cesium ions (Cs + ), B includes but is not limited to Pb 2+ 、Sn 2+ .

[0108] Furthermore, the thickness of the first passivation layer 4 is 1 nm to 30 nm, such as 5 nm, 10 nm or 25 nm. The thickness of the light absorbing layer 5 is 300 nm to 1200 nm, such as 500 nm, 600 nm, 700 nm or 1000 nm.

[0109] As a preferred embodiment, see Figure 3 The perovskite solar cell further includes: a second passivation layer 8 located on the surface of the light absorbing layer 5 facing away from the substrate 1. The material of the second passivation layer 8 is a two-dimensional perovskite material, and the band gap of the second passivation layer 8 is larger than the band gap of the light absorbing layer 5; a second carrier transport layer 6 located on the surface of the second passivation layer 8 facing away from the light absorbing layer 5. The formation of the second passivation layer reduces the amount of residual metal halide between the light absorbing layer and the second carrier transport layer, thereby passivating the interface defects between the light absorbing layer and the second carrier transport layer; a high-low junction structure is formed at the interface between the second passivation layer 8 and the light absorbing layer 5, which facilitates the transport of second carriers generated by the light absorbing layer 5 to the second carrier transport layer 6. In summary, the formation of the second passivation layer can further improve the photoelectric conversion performance of the perovskite solar cell. In addition, the two-dimensional perovskite material has excellent structural stability and photostability. Therefore, the presence of the second passivation layer can further improve the structural stability of the perovskite solar cell.

[0110] Specifically, the difference between the band gap of the second passivation layer 8 and the band gap of the light absorbing layer 5 is 0.5 eV-1.5 eV, for example, 1.0 eV.

[0111] Furthermore, the material of the second passivation layer 8 includes M2A n-1 B n X 3n+1 , M includes: tetrabutylammonium cation (TBA + ), dimethylamine cation (DMA + ), triethylamine cation (TEA + ), phenylethylamine cation (PEA + ), p-fluorophenethylamine cation (pF-PEA+ ), butylamine cation (BA + ), isopropylamine cation (2-PA + ), octylamine cation (OA + ), tetrafluorobenzylamine cation (p-FPMA + ), tribromophenethylamine cation (3-Br-PEA + ) and phenylpropylamine cation (PPA + ), A includes a methylamino group (MA + ), formamidine group (FA + ) and cesium ions (Cs + ), B includes lead ions (Pb 2+ ) and tin son( Sn 2+ ） At least one of the following, X is a halogen anion, and the value of n is 2-6.

[0112] The material of the second passivation layer 8 may be the same as or different from the material of the first passivation layer 4 .

[0113] Furthermore, the thickness of the second passivation layer 8 is 1 nm-30 nm, for example, 5 nm, 10 nm or 25 nm.

[0114] The following provides specific embodiments to clearly and completely describe the technical solutions of the present invention.

[0115] Example 1

[0116] This embodiment provides a method for preparing a perovskite solar cell, comprising:

[0117] The FTO conductive glass was pretreated; the specific steps were as follows: the FTO conductive glass was cleaned to remove surface impurities; the FTO conductive glass was ultrasonically treated with glass detergent, deionized water, ethanol, acetone, isopropanol, and ethanol for 15 minutes in sequence; the FTO conductive glass was blown dry with dry air, and then treated with UV-ozone for 20 minutes;

[0118] A 20 nm layer of nickel oxide was deposited on the surface of the FTO layer of the FTO conductive glass using a spin coating process as a hole transport layer. The solution for forming the hole transport layer contained water as the solvent and NiO as the solute. x , the concentration of the solute is 20 mg / ml;

[0119] A first organic amine salt solution with a solute concentration of 0.008 mol / L was sprayed on the surface of the hole transport layer facing away from the FTO conductive glass. The solute of the first organic amine salt solution was tetrafluorobenzyl ammonium iodide and the solvent was isopropyl alcohol. The layer was then annealed at 100°C for 5 minutes to obtain an organic amine salt layer with a thickness of 10 nm.

[0120] A 250nm lead iodide layer was formed on the side of the organic amine salt layer facing away from the FTO conductive glass using a vacuum evaporation process. The deposition rate of the lead iodide layer was 20Å / s.

[0121] An organic liquid film was formed on the side of the lead iodide layer facing away from the FTO conductive glass using a spin coating process. The organic solution for forming the organic liquid film included 0.5 mol / L methylammonium iodide (FAI), 0.1 mol / L methylammonium chloride (MACl), and 0.2 mol / L methylammonium bromide (MABr) in isopropyl alcohol.

[0122] Annealing at 100°C for 5 min to obtain a first passivation layer with a thickness of 10 nm and a light absorption layer with a thickness of 500 nm. The material of the first passivation layer is (p-FPMA)2Pb(I 0.8 Br 0.2 )4, the material of the light absorbing layer is MA 0.29 FA 0.71 Pb(Br 0.2 I 0.8 )3.

[0123] A 20nm thick C60 layer, a 5nm thick BCP layer and a 100nm thick silver layer were sequentially deposited on the surface of the light absorption layer using a vacuum evaporation process to obtain a perovskite solar cell.

[0124] Example 2

[0125] This embodiment provides a method for preparing a perovskite solar cell, which differs from the method for preparing a perovskite solar cell provided in Example 1 in that the concentration of the solute in the first organic amine salt solution is 0.01 mol / L.

[0126] Example 3

[0127] This embodiment provides a method for preparing a perovskite solar cell, which differs from the method for preparing a perovskite solar cell provided in Example 1 in that the concentration of the solute in the first organic amine salt solution is 1 mol / L.

[0128] Example 4

[0129] This embodiment provides a method for preparing a perovskite solar cell. The difference between this method and the method for preparing a perovskite solar cell provided in Example 1 is that after forming the light absorbing layer, a second passivation layer is formed on the surface of the light absorbing layer facing away from the substrate by a spraying process.

[0130] Specifically, the second organic amine salt solution used to form the second passivation layer has the same composition as the first organic amine salt solution, the steps and parameters for forming the second passivation layer are the same as the steps and parameters for forming the first passivation layer, and the material and thickness of the second passivation layer finally obtained are also the same as the material and thickness of the first passivation layer.

[0131] Example 5

[0132] This embodiment provides a method for preparing a perovskite solar cell. The difference between this method and the method for preparing a perovskite solar cell provided in Example 1 is that the solute of the first organic amine salt solution is benzyl ammonium iodide, and the material of the first passivation layer finally obtained is (PMA)2Pb(I 0.8 Br 0.2 )4.

[0133] Example 6

[0134] This embodiment provides a method for preparing a perovskite solar cell. The difference between this method and the method for preparing a perovskite solar cell provided in Example 1 is that the solute of the first organic amine salt solution is phenethylammonium iodide, and the material of the first passivation layer finally obtained is (PEA)2Pb(I 0.8 Br 0.2 )4.

[0135] Example 7

[0136] This embodiment provides a method for preparing a perovskite-silicon solar cell, comprising:

[0137] Provide crystalline silicon cells and perform UV ozone treatment on them;

[0138] The magnetron sputtering process was used to deposit 20nm of nickel oxide as a hole transport layer on one side of the crystalline silicon cell. The vacuum degree in the magnetron sputtering chamber during the deposition process was 5*10 -6 millibar;

[0139] A first organic amine salt solution was spin-coated on the surface of the hole transport layer facing away from the crystalline silicon cell. The concentration of the solute of the first organic amine salt solution was 0.01 mol / L. The solute of the first organic amine salt solution was ethylammonium chloride and the solvent was isopropyl alcohol. The solution was then annealed at 100° C. for 10 minutes to obtain an organic amine salt layer with a thickness of 10 nm.

[0140] A 200nm thick lead iodide layer is formed on the surface of the organic amine salt layer facing away from the crystalline silicon cell by vacuum evaporation process. The vacuum degree in the evaporation chamber during the evaporation process is 2*10 -6 mbar, the deposition rate of the lead iodide layer was 10 Å / s;

[0141] An organic liquid film is formed on the side of the lead iodide layer facing away from the crystalline silicon cell using a spray coating process. The organic solution forming the organic liquid film includes 0.4 mol / L methylammonium iodide (FAI), 0.02 mol / L methylammonium chloride (MACl), and 0.1 mol / L methylammonium bromide (MABr), with the solvent being isopropyl alcohol.

[0142] Annealing at 100°C for 10 min to obtain a first passivation layer with a thickness of 10 nm and a light absorption layer with a thickness of 500 nm. The material of the first passivation layer is (EA)2Pb(I 0.8 Br 0.2 )4, the material of the light absorbing layer is MA 0.2 FA 0.8 Pb(Br 0.2 I 0.8 )3.

[0143] A 20nm thick fullerene C60 derivative layer, a 5nm thick BCP (baconychloride) layer and a 10nm thick silver layer were sequentially deposited on the surface of the light absorption layer by vacuum evaporation to obtain a stacked perovskite solar cell.

[0144] Example 8

[0145] This embodiment provides a method for preparing a perovskite solar cell, which differs from the method for preparing a perovskite solar cell provided in Example 5 in that: after forming the light absorption layer, a second passivation layer is formed on the surface of the light absorption layer facing away from the substrate by a spraying process;

[0146] Specifically, the second organic amine salt solution used to form the second passivation layer has the same composition as the first organic amine salt solution, the steps and parameters for forming the second passivation layer are the same as the steps and parameters for forming the first passivation layer, and the material and thickness of the second passivation layer finally obtained are also the same as the material and thickness of the first passivation layer.

[0147] Comparative Example 1

[0148] This comparative example provides a method for preparing a perovskite solar cell, which differs from the method for preparing a perovskite solar cell provided in Example 1 in that after forming the hole transport layer, a light absorption layer is directly formed on the surface of the hole transport layer without forming an organic amine salt layer.

[0149] Comparative Example 2

[0150] This comparative example provides a method for preparing a perovskite solar cell, which differs from the method for preparing a perovskite solar cell provided in Example 5 in that after forming the hole transport layer, a light absorption layer is directly formed on the surface of the hole transport layer without forming an organic amine salt layer.

[0151] Comparative Example 3

[0152] This comparative example provides a method for preparing a perovskite solar cell, which differs from the method for preparing a perovskite solar cell provided in Example 6 in that after forming the hole transport layer, a light absorption layer is directly formed on the surface of the hole transport layer without forming an organic amine salt layer.

[0153] Comparative Example 4

[0154] This comparative example provides a method for preparing a perovskite stacked silicon solar cell, which differs from the method for preparing a perovskite solar cell provided in Example 7 in that after forming the hole transport layer, a light absorption layer is directly formed on the surface of the hole transport layer, and an organic amine salt layer is no longer formed.

[0155] Test Example 1

[0156] The photoelectric conversion performance of the perovskite solar cells prepared in Examples 1-8 and Comparative Examples 1-4 was tested, and the test results are shown in Table 1. oc Refers to the open circuit voltage, J sc It refers to short-circuit current density, FF refers to fill factor, and PCE refers to photoelectric conversion efficiency.

[0157] Table 1

[0158]

[0159] Test Example 2

[0160] The stability test was performed on the perovskite solar cells prepared in Examples 1-8 and Comparative Examples 1-4. Specifically, without encapsulation, the perovskite solar cells were heated at 85°C for 3000 hours and subjected to a photoelectric conversion test. The test results are as follows:

[0161] The photoelectric conversion efficiency of the perovskite solar cell prepared in Example 1 is 70% of the initial efficiency;

[0162] The photoelectric conversion efficiency of the perovskite solar cell prepared in Example 2 is 70% of the initial efficiency;

[0163] The photoelectric conversion efficiency of the perovskite solar cell prepared in Example 3 is 75% of the initial efficiency;

[0164] The photoelectric conversion efficiency of the perovskite solar cell prepared in Example 4 is 73% of the initial efficiency;

[0165] The photoelectric conversion efficiency of the perovskite solar cell prepared in Example 5 is 68% of the initial efficiency;

[0166] The photoelectric conversion efficiency of the perovskite solar cell prepared in Example 6 is 77% of the initial efficiency;

[0167] The photoelectric conversion efficiency of the perovskite solar cell prepared in Example 7 is 80% of the initial efficiency;

[0168] The photoelectric conversion efficiency of the perovskite solar cell prepared in Example 8 is 79% of the initial efficiency;

[0169] The photoelectric conversion efficiency of the perovskite solar cell prepared in Comparative Example 1 is 65% of the initial efficiency;

[0170] The photoelectric conversion efficiency of the perovskite solar cell prepared in Comparative Example 2 is 63% of the initial efficiency;

[0171] The photoelectric conversion efficiency of the perovskite solar cell prepared in Comparative Example 3 is 59% of the initial efficiency;

[0172] The photoelectric conversion efficiency of the perovskite solar cell prepared in Comparative Example 4 is 62% of the initial efficiency.

[0173] It should be understood that the initial efficiency is the photoelectric conversion efficiency before the perovskite solar cell is heated.

[0174] Obviously, the above embodiments are merely examples for clarity of explanation and are not intended to limit the implementation methods. Those skilled in the art will readily appreciate that other variations or modifications based on the above descriptions are possible. It is not necessary and impossible to enumerate all implementation methods here. Obvious variations or modifications arising therefrom remain within the scope of protection of the present invention.

Claims

1. A method for preparing a perovskite solar cell, characterized in that: include: providing a substrate; forming a first electrode layer on one surface of the substrate; forming a first carrier transport layer on a surface of the first electrode layer facing away from the substrate; forming an organic amine salt layer on a surface of the first carrier transport layer facing away from the substrate; A metal halide salt layer is formed on a surface of the organic amine salt layer facing away from the substrate using a dry process, an organic liquid film is formed on a surface of the metal halide salt layer facing away from the substrate, the organic liquid film is subjected to a first annealing, the organic liquid film reacts with the metal halide salt layer to generate a light absorption layer, the organic amine salt layer reacts with the light absorption layer to generate a first passivation layer, the first passivation layer is located on a surface of one side of the light absorption layer, the material of the light absorption layer is a three-dimensional perovskite material, the material of the first passivation layer is a two-dimensional perovskite material, and the band gap of the first passivation layer is greater than the band gap of the light absorption layer.

2. The method for preparing a perovskite solar cell according to claim 1, wherein: The material of the organic amine salt layer includes at least one of tetrabutylammonium bromide, tetrabutylammonium iodide, dimethylammonium iodide, triethylammonium iodide, phenethylammonium iodide, p-fluorophenethylammonium iodide, phenethylammonium bromide, butylammonium bromide, isopropylammonium bromide, octylammonium iodide, tetrafluorobenzylammonium iodide, tribromophenethylammonium iodide, phenpropylammonium iodide and tetrafluorophenethylammonium bromide.

3. The method for preparing a perovskite solar cell according to claim 1, wherein: The step of forming an organic amine salt layer on a surface of the first carrier transport layer facing away from the substrate comprises: preparing a first organic amine salt solution, forming a first organic amine salt liquid film on a surface of the first carrier transport layer facing away from the substrate, and performing a second annealing on the first organic amine salt liquid film to obtain the organic amine salt layer; Alternatively, the organic amine salt layer is formed on a surface of the first carrier transport layer facing away from the substrate by a vacuum evaporation process.

4. The method for preparing a perovskite solar cell according to claim 3, wherein: The process of forming the first organic amine salt liquid film includes a slit coating process, a doctor blade coating process, a spray coating process, a spin coating process or an immersion process.

5. The method for preparing a perovskite solar cell according to claim 3, wherein: The concentration of the solute in the first organic amine salt solution is 0.005 mol / L-1 mol / L, and the solvent of the first organic amine salt solution includes at least one of dimethylamide, dimethyl sulfoxide, N-methylpyrrolidone, ethanol, methanol, and isopropanol.

6. The method for preparing a perovskite solar cell according to claim 3, wherein: The temperature of the second annealing is 50° C.-120° C., and the time of the second annealing is 5 min-30 min.

7. The method for preparing a perovskite solar cell according to claim 1, wherein: The dry process includes a vacuum evaporation process, a magnetron sputtering process, a chemical vapor deposition process, an atomic deposition process or a reactive plasma deposition process; The process of forming an organic liquid film on the surface of the metal halide layer facing away from the substrate includes a slit coating process, a scraping process, a spraying process, a spin coating process or an immersion process; during the process of forming the organic liquid film and the first annealing process, the substrate is in a nitrogen atmosphere or an inert atmosphere.

8. The method for preparing a perovskite solar cell according to claim 7, wherein: The deposition rate of the metal halide salt layer is 0.5Å / s-50Å / s.

9. The method for preparing a perovskite solar cell according to claim 7, wherein: The concentration of the organic liquid membrane is 0.2 mol / L-1 mol / L.

10. The method for preparing a perovskite solar cell according to claim 1, wherein: The thickness of the organic amine salt layer is 1 nm to 100 nm; the thickness of the metal halide salt layer is 10 nm to 2000 nm.

11. The method for preparing a perovskite solar cell according to claim 10, wherein: The thickness of the organic amine salt layer is 5nm-20nm; the thickness of the metal halide salt layer is 100nm-1000nm.

12. The method for preparing a perovskite solar cell according to any one of claims 1 to 11, characterized in that: Also includes: After forming the light absorbing layer, forming a second passivation layer on a surface of the light absorbing layer facing away from the substrate, wherein the material of the second passivation layer is a two-dimensional perovskite material, and the band gap of the second passivation layer is larger than the band gap of the light absorbing layer; A second carrier transport layer is formed on a surface of the second passivation layer facing away from the light absorbing layer.

13. The method for preparing a perovskite solar cell according to claim 12, wherein: The step of forming a second passivation layer on a surface of the light absorbing layer facing away from the substrate comprises: A second organic amine salt solution is prepared to form a second organic amine salt liquid film on the surface of the light absorbing layer facing away from the substrate. The second organic amine salt liquid film is subjected to a third annealing to convert the second organic amine salt liquid film into a second passivation layer.

14. The method for preparing a perovskite solar cell according to claim 13, wherein: The process of forming the second organic amine salt liquid film includes a slit coating process, a doctor blade coating process, a spray coating process or a spin coating process.

15. The method for preparing a perovskite solar cell according to claim 13, wherein: The concentration of the solute in the second organic amine salt solution is 0.005 mol / L-1 mol / L, and the solvent of the second organic amine salt solution includes at least one of dimethylamide, dimethyl sulfoxide, N-methylpyrrolidone, ethanol, methanol and isopropanol.

16. The method for preparing a perovskite solar cell according to claim 13, wherein: The material of the solute in the second organic amine salt solution includes at least one of tetrabutylammonium bromide, tetrabutylammonium iodide, dimethylammonium iodide, triethylammonium iodide, phenethylammonium iodide, p-fluorophenethylammonium iodide, phenethylammonium bromide, butylammonium bromide, isopropylammonium bromide, octylammonium iodide, tetrafluorobenzylammonium iodide, tribromophenethylammonium iodide, phenpropylammonium iodide and tetrafluorophenethylammonium bromide.

17. The method for preparing a perovskite solar cell according to claim 13, wherein: The temperature of the third annealing is 50° C.-120° C., and the time of the third annealing is 5 min-30 min.

18. A perovskite solar cell, characterized in that: include: substrate; a first electrode layer located on one side surface of the substrate; a first carrier transport layer located on a surface of the first electrode layer facing away from the substrate; a first passivation layer located on a surface of the first carrier transport layer facing away from the substrate, wherein the first passivation layer is made of a two-dimensional perovskite material; a light absorbing layer located on a surface of the first passivation layer facing away from the substrate, wherein the light absorbing layer is made of a three-dimensional perovskite material, and the band gap of the first passivation layer is greater than the band gap of the light absorbing layer; The perovskite solar cell is prepared by the preparation method according to any one of claims 1 to 17.

19. The perovskite solar cell according to claim 18, characterized in that The difference between the band gap of the first passivation layer and the band gap of the light absorbing layer is 0.5 eV-1.5 eV.

20. The perovskite solar cell according to claim 19, characterized in that The thickness of the first passivation layer is 1 nm-30 nm; the thickness of the light absorption layer is 300 nm-1200 nm.

21. The perovskite solar cell according to claim 18 or 19, characterized in that Also includes: a second passivation layer located on a surface of the light absorbing layer facing away from the substrate, wherein the material of the second passivation layer is a two-dimensional perovskite material, and the band gap of the second passivation layer is larger than the band gap of the light absorbing layer; A second carrier transport layer is located on a surface of the second passivation layer facing away from the light absorbing layer.

22. The perovskite solar cell according to claim 21, wherein The difference between the band gap of the second passivation layer and the band gap of the light absorbing layer is 0.5 eV-1.5 eV.

23. The perovskite solar cell according to claim 21, characterized in that The thickness of the second passivation layer is 1 nm to 30 nm; the thickness of the light absorption layer is 300 nm to 1200 nm.

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