Perovskite solar cell and preparation method thereof

Abstract

The application provides a perovskite solar cell and a preparation method thereof. The perovskite solar cell comprises a substrate, a first electrode layer, a first carrier transport layer, a three-dimensional perovskite layer, a passivation layer, a second carrier transport layer and a second electrode layer which are sequentially stacked. The passivation layer is in contact with the three-dimensional perovskite layer and the second carrier transport layer. The passivation layer comprises a first passivation material and a second passivation material which are uniformly mixed. The first passivation material is an organic halide salt. The second passivation material comprises at least one of an amino group, a carboxyl group, a phosphine group and a sulfonic acid group. The passivation layer between the three-dimensional perovskite layer and the second carrier transport layer can passivate interface defects. The first passivation material in the passivation layer can passivate iodine defects, and the second passivation material in the passivation layer can passivate lead defects. The first passivation material and the second passivation material are mutually synergistic, so that the open-circuit voltage, the short-circuit current density and the fill factor of the perovskite solar cell are effectively improved, and the photoelectric conversion efficiency of the perovskite solar cell is effectively improved.

Description

Technical Field

[0001] This invention relates to the field of perovskite solar cell technology, specifically to a perovskite solar cell and its fabrication method. Background Technology

[0002] With the increasing severity of global ecological and energy shortages, solar photovoltaic power generation has received widespread attention. Perovskite solar cells, as a third-generation type of solar cell, have become a rising star in the field of solar cells due to their advantages such as low cost, simple fabrication process, and high efficiency. In just over a decade, the efficiency of perovskite solar cells has increased from 3.8% to 25.8%, demonstrating enormous potential. A perovskite solar cell comprises a substrate, a first electrode, a first carrier transport layer, a perovskite layer, a second carrier transport layer, and a second electrode, stacked sequentially.

[0003] However, there are many defects at the interface between the perovskite layer and the carrier transport layer, such as iodine defects and lead defects. The presence of these interface defects not only causes a loss of photoelectric conversion efficiency but also affects the battery life. Summary of the Invention

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

[0005] This invention provides a perovskite solar cell, comprising a substrate, a first electrode layer, a first carrier transport layer, a three-dimensional perovskite layer, a passivation layer, and a second carrier transport layer stacked sequentially. The passivation layer is in contact with the three-dimensional perovskite layer and the second carrier transport layer. The passivation layer comprises a uniformly mixed first passivation material and a second passivation material. The first passivation material is an organic halide salt, and the second passivation material comprises at least one of amino, carboxyl, phosphonoyl, and sulfonic acid groups.

[0006] Optionally, the first passivating material includes at least one of n-butylamine hydroiodide, n-hexylamine hydroiodide, n-octylamine hydroiodide, oleylamine hydroiodide, phenethylamine hydroiodide, naphthylamine hydroiodide, methylpyridine hydroiodide, methylimidazolium hydroiodide, methylcarbazole hydroiodide, and methylthiophene hydroiodide.

[0007] Optionally, the second passivating material includes at least one of 2-quinoxalocarboxylic acid, bis(trifluoromethanesulfonyl)imide, 2-pyridyltrifluoromethoxybenzylimide, (5-mercapto-1,3,4-thiadiazol-2-ylthio)acetic acid, 4-imidazolium acetate hydrochloride, 3-(1-naphthyl)-L-alanine hydrochloride, theophylline-7-acetic acid, tenofovir, 3-(1-pyridyl)propanesulfonate, 9-[2-(diethoxyphosphonomethoxy)ethyl]adenine, and adenosine monophosphate.

[0008] Optionally, the molar ratio of the first passivating material to the second passivating material is 1-300.

[0009] Optionally, the molar ratio of the first passivating material to the second passivating material is 1-50.

[0010] Optionally, the thickness of the passivation layer is 1nm-30nm.

[0011] Optionally, the thickness of the passivation layer is 5nm-10nm.

[0012] Optionally, the substrate may include glass, a flexible substrate, a heterojunction cell, a crystalline silicon cell, or a thin-film solar cell.

[0013] The present invention also provides a method for fabricating a perovskite solar cell, comprising: sequentially forming a first electrode layer, a first carrier transport layer, a three-dimensional perovskite layer, a passivation layer, and a second carrier transport layer on one side surface of a substrate, wherein the substrate, the first electrode layer, the first carrier transport layer, the three-dimensional perovskite layer, the passivation layer, and the second carrier transport layer are sequentially stacked, and the passivation layer is in contact with the three-dimensional perovskite layer and the second carrier transport layer, wherein the passivation layer comprises a uniformly mixed first passivation material and a second passivation material, wherein the first passivation material is an organic halide salt, and the second passivation material comprises at least one selected from amino, carboxyl, phosphonoyl, and sulfonic acid groups.

[0014] Optionally, the step of forming the passivation layer includes: preparing a passivation solution, wherein the solute of the passivation solution includes a first passivation material and a second passivation material; using the passivation solution to form a passivation liquid film on the surface of the three-dimensional perovskite layer away from the first carrier transport layer; and annealing the passivation liquid film.

[0015] Optionally, the annealing temperature is 60℃-120℃, and the annealing time is 5min-10min.

[0016] Optionally, the concentration of the solute in the passivation solution is 0.05 mg / ml to 0.35 mg / ml.

[0017] Optionally, the solvent of the passivation solution includes at least one of methanol and isopropanol.

[0018] Optionally, the passivation liquid film can be formed on the surface of the three-dimensional perovskite layer using a spin coating method.

[0019] Optionally, the spin coating speed is 2000 r / min-5000 r / min.

[0020] The technical solution of this invention has the following advantages:

[0021] 1. The perovskite solar cell provided by the present invention has a passivation layer located between the three-dimensional perovskite layer and the second carrier transport layer, which can passivate interface defects. The first passivation material in the passivation layer can passivate iodine defects, and the second passivation material in the passivation layer can passivate lead defects. The first passivation material and the second passivation material work together to effectively improve the open-circuit voltage, short-circuit current density and fill factor of the perovskite solar cell, thereby effectively improving the photoelectric conversion efficiency of the perovskite solar cell.

[0022] 2. The method for fabricating perovskite solar cells provided by the present invention forms a passivation layer on the surface of a three-dimensional perovskite layer, thereby simultaneously passivating iodine defects and lead defects at the interface between the three-dimensional perovskite layer and the second carrier transport layer. This effectively improves the open-circuit voltage, short-circuit current density, and fill factor of the perovskite solar cell, thereby effectively improving the photoelectric conversion efficiency of the perovskite solar cell. Attached Figure Description

[0023] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0024] Figure 1 A schematic diagram of the structure of a solar cell provided in an embodiment of the present invention;

[0025] Explanation of reference numerals in the attached figures:

[0026] 1-Substrate; 2-First electrode layer; 3-First carrier transport layer; 4-Three-dimensional perovskite layer; 5-Passivation layer; 6-Second carrier transport layer; 7-Second electrode layer. Detailed Implementation

[0027] The technical solution of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] In the description of this invention, it should be noted that the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0029] See Figure 1This embodiment provides a perovskite solar cell, comprising a substrate 1, a first electrode layer 2, a first carrier transport layer 3, a three-dimensional perovskite layer 4, a passivation layer 5, a second carrier transport layer 6, and a second electrode layer 7 stacked sequentially. The passivation layer is in contact with the three-dimensional perovskite layer and the second carrier transport layer. The passivation layer comprises a uniformly mixed first passivation material and a second passivation material. The first passivation material is an organic halide salt, and the second passivation material comprises at least one of amino, carboxyl, phosphonoyl, and sulfonic acid groups.

[0030] In the aforementioned perovskite solar cell, the passivation layer located between the three-dimensional perovskite layer and the second carrier transport layer can passivate interface defects. Specifically, the first passivation material in the passivation layer can passivate iodine defects, and the second passivation material in the passivation layer can passivate lead defects. The first and second passivation materials work together to effectively improve the open-circuit voltage, short-circuit current density, and fill factor of the perovskite solar cell, thereby effectively improving the photoelectric conversion efficiency of the perovskite solar cell.

[0031] It should be noted that when the passivation layer is made of only the first passivation material (organic halide salt), although it passivates the iodine defects at the interface, it reduces the carrier mobility, increasing the open-circuit voltage of the perovskite solar cell while decreasing the short-circuit current density. The second passivation material can passivate the lead defects at the interface, thereby reducing non-radiative recombination, increasing both the open-circuit voltage and the short-circuit current density of the perovskite solar cell. In other words, using both the first and second passivation materials to prepare the passivation layer not only significantly increases the open-circuit voltage of the perovskite solar cell but also increases its short-circuit current density, thus significantly increasing the photoelectric conversion efficiency of the perovskite solar cell. This makes the photoelectric conversion efficiency of the perovskite solar cell superior to that of the perovskite solar cell that uses only the first or second passivation material to prepare the passivation layer.

[0032] Specifically, the first passivating material includes at least one of n-butylamine hydroiodate, n-hexylamine hydroiodate, n-octylamine hydroiodate, oleylamine hydroiodate, phenethylamine hydroiodate, naphthylamine hydroiodate, methylpyridine hydroiodate, methylimidazolium hydroiodate, methylcarbazole hydroiodate, and methylthiophene hydroiodate. The second passivating material includes at least one of 2-quinoxalocarboxylic acid, bis(trifluoromethanesulfonyl)imide, 2-pyridyltrifluoromethoxybenzylimide, (5-mercapto-1,3,4-thiadiazol-2-ylthio)acetic acid, 4-imidazolium acetate hydrochloride, 3-(1-naphthyl)-L-alanine hydrochloride, theophylline-7-acetic acid, tenofovir, 3-(1-pyridyl)propanesulfonate, 9-[2-(diethoxyphosphonomethoxy)ethyl]adenine, and adenosine monophosphate.

[0033] Further, the molar ratio of the first passivating material to the second passivating material is 1-300. For example, the molar ratio of the first passivating material to the second passivating material can be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 30, 40, 50, 60, 70, 80, 90, 100, 125, 150, 175, 200, 225, 250, 275, or 300. Preferably, the molar ratio of the first passivating material to the second passivating material is 1-50.

[0034] Further, the thickness of the passivation layer is 1nm-30nm; for example, the thickness of the passivation layer can be 1nm, 3nm, 5nm, 7nm, 10nm, 13nm, 15nm, 17nm, 20nm, 23nm, 25nm, 27nm, or 30nm. Preferably, the thickness of the passivation layer is 5nm-10nm.

[0035] Specifically, the substrate includes, but is not limited to, glass, flexible substrates, heterojunction cells, crystalline silicon cells, or thin-film solar cells; flexible substrates include, but are not limited to, polyethylene naphthalate (PEN) and polyethylene terephthalate (PET); thin-film solar cells include, but are not limited to, copper indium gallium selenide (CIGS) thin-film solar cells, cadmium telluride (CdTe) thin-film solar cells, gallium arsenide (GaAs) thin-film solar cells, and perovskite solar cells; crystalline silicon cells include, but are not limited to, N-type monocrystalline passivated contact cells (TopCon cells). When the substrate is glass or a flexible substrate, the final cell fabricated is a single-junction perovskite cell; when the substrate is a heterojunction cell, crystalline silicon cell, or thin-film solar cell, the final cell fabricated is a tandem cell.

[0036] The material of the first electrode layer 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 or PEN, and the material of the first electrode layer is FTO or ITO, commercially available FTO conductive glass, ITO conductive glass, or PEN / ITO can be used directly.

[0037] One of the first carrier transport layer and the second carrier transport layer 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 solar 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 solar cell is a conventional perovskite solar cell.

[0038] The general structural formula of three-dimensional perovskites is ABX3, where A is a monovalent cation, B is a divalent cation, and X is a halide anion. A includes, but is not limited to, a methylamino group (MA). + ), formamidin group (FA)+ or cesium ions (Cs) + B includes, but is not limited to, Pb. 2+ Sn 2+ Furthermore, the thickness of the three-dimensional perovskite layer is 200nm-1000nm. For example, the thickness of the three-dimensional perovskite layer can be 200nm, 300nm, 400nm, 500nm, 600nm, 700nm, 800nm, 900nm or 1000nm.

[0039] The material of the second electrode layer includes, but is not limited to, gold, silver, and aluminum.

[0040] This embodiment also provides a method for fabricating the above-mentioned perovskite solar cell, including the following steps: sequentially forming a first electrode layer, a first carrier transport layer, a three-dimensional perovskite layer, a passivation layer, a second carrier transport layer, and a second electrode layer on one side surface of a substrate, see [link to previous embodiment]. Figure 1 The substrate 1, the first electrode layer 2, the first carrier transport layer 3, the three-dimensional perovskite layer 4, the passivation layer 5, and the second carrier transport layer 6 are sequentially stacked, and the passivation layer 5 is in contact with the three-dimensional perovskite layer 4 and the second carrier transport layer 6. The passivation layer 5 includes a uniformly mixed first passivation material and a second passivation material. The first passivation material is an organic halide salt, and the second passivation material includes at least one of amino, carboxyl, phosphonoyl, and sulfonic acid groups.

[0041] The following provides a clear and complete description of an exemplary method for fabricating perovskite solar cells.

[0042] Step S1: Provide substrate 1.

[0043] Step S2: Form a first electrode layer 2 on one side surface of the substrate 1. Specifically, the process for forming the first electrode layer on one side surface of the substrate includes, but is not limited to, magnetic sputtering or chemical vapor deposition.

[0044] Step S3: A first carrier transport layer 3 is formed on the surface of the first electrode layer 2 facing away from the substrate 1. Specifically, the methods for forming the first carrier transport layer include, but are not limited to, spin coating, coating method, vacuum evaporation method, and magnetron sputtering method. The preparation method can be selected according to the material of the first carrier transport layer.

[0045] Step S4: A three-dimensional perovskite layer 4 is formed on the surface of the first carrier transport layer 3 facing away from the substrate 1. Specifically, the methods for forming the three-dimensional perovskite layer include, but are not limited to, spin coating and plating.

[0046] Step S5: A passivation layer 5 is formed on the surface of the three-dimensional perovskite layer 4 facing away from the substrate 1.

[0047] In one embodiment, the step of forming a passivation layer on the surface of the three-dimensional perovskite layer facing away from the substrate includes: preparing a passivation solution, wherein the solute of the passivation solution includes a first passivation material and a second passivation material, and the solvent includes at least one of methanol and isopropanol; forming a passivation liquid film on the surface of the three-dimensional perovskite layer facing away from the first carrier transport layer using the passivation solution; and annealing the passivation liquid film. It should be understood that the method for forming the passivation layer includes, but is not limited to, the method described above.

[0048] Further, in the passivation solution, the molar ratio of the first passivating material to the second passivating material is 1-300. For example, the molar ratio of the first passivating material to the second passivating material can be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 30, 40, 50, 60, 70, 80, 90, 100, 125, 150, 175, 200, 225, 250, 275, or 300. Preferably, in the passivation solution, the molar ratio of the first passivating material to the second passivating material is 1-50.

[0049] Furthermore, the concentration of the solute in the passivation solution is 0.05 mg / ml to 0.35 mg / ml.

[0050] Furthermore, the methods for forming the passivation liquid film include, but are not limited to, spin coating and coating methods. When forming the passivation liquid film on the surface of the three-dimensional perovskite layer using spin coating, the spin coating speed is 2000 r / min-5000 r / min; for example, the spin coating speed can be 2000 r / min, 2500 r / min, 3000 r / min, 3500 r / min, 4000 r / min, 4500 r / min or 5000 r / min.

[0051] Optionally, the annealing temperature is 60℃-120℃, and the annealing time is 5min-10min. For example, the annealing temperature can be 60℃, 70℃, 80℃, 90℃, 100℃, 110℃, or 120℃, and the annealing time can be 5min, 6min, 7min, 8min, 9min, or 10min. The higher the annealing temperature, the shorter the annealing time.

[0052] Step S6: Form a second carrier transport layer 6 on the surface of the passivation layer 5 facing away from the substrate 1. Specifically, the method for forming the second carrier transport layer includes, but is not limited to, spin coating, coating method, vacuum evaporation, and magnetron sputtering. The preparation method can be selected according to the material of the second carrier transport layer.

[0053] Step S7: A second electrode layer 7 is formed on the surface of the second carrier transport layer 6 facing away from the substrate 1, resulting in... Figure 1 The perovskite solar cell shown. Specifically, methods for forming the second electrode layer include, but are not limited to, vacuum evaporation.

[0054] The following specific embodiments clearly and completely describe the technical solution of the present invention. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0055] Example 1

[0056] This embodiment provides a method for fabricating a perovskite solar cell, including the following steps:

[0057] Prepare a passivation solution. The solutes in the passivation solution include oleylamine hydroiodate and 2-quinoxalocarboxylic acid. The molar ratio of oleylamine hydroiodate to 2-quinoxalocarboxylic acid is 5. The solvent is methanol, and the concentration of the solute is 0.08 mg / ml.

[0058] FTO conductive glass is provided, and an electron transport layer is formed on the surface of the FTO layer of the FTO conductive glass by spin coating. The electron transport layer is made of TiO2 and has a thickness of 10nm.

[0059] A three-dimensional perovskite layer was formed on the surface of the electron transport layer by spin coating. The material of the three-dimensional perovskite layer was MAPbI3 and the thickness was 400 nm.

[0060] The passivation layer is formed on the surface of the three-dimensional perovskite layer. The specific steps include: using spin coating to form a passivation liquid film on the surface of the three-dimensional perovskite layer with a passivation solution, the rotation speed is 4000 r / min; the passivation liquid film is annealed at a temperature of 80℃ for 8 min to obtain a passivation layer with a thickness of 12 nm.

[0061] A hole transport layer was formed on the surface of the passivation layer by spin coating. The hole transport layer was made of CuSCN and had a thickness of 15 nm. A second electrode layer was formed on the surface of the hole transport layer by vacuum evaporation. The second electrode layer was made of silver and had a thickness of 100 nm, thus obtaining a perovskite solar cell.

[0062] The photoelectric conversion efficiency of the prepared perovskite solar cell was tested, showing an initial efficiency of 22.15%, an open-circuit voltage of 1.19 V, and a short-circuit current density of 24.12 mA / cm². 2 The fill factor was 77.16%; the prepared perovskite solar cell maintained 95% of its initial efficiency after operating for 1700 h at 85℃ and 85% RH.

[0063] Example 2

[0064] This embodiment provides a method for fabricating a perovskite solar cell, including the following steps:

[0065] Prepare a passivation solution. The solutes in the passivation solution include n-octylamine hydroiodate and bis(trifluoromethanesulfonyl)imide. The molar ratio of n-octylamine hydroiodate to bis(trifluoromethanesulfonyl)imide is 4.5. The solvent is isopropanol, and the concentration of the solute is 0.15 mg / ml.

[0066] ITO conductive glass is provided, and a hole transport layer is formed on the surface of the ITO layer of the ITO conductive glass using a spin coating method. The material of the hole transport layer is NiO. x The hole transport layer is 10 nm thick;

[0067] A three-dimensional perovskite layer was formed on the surface of the hole transport layer by spin coating. The material of the three-dimensional perovskite layer was CsPbI3 and the thickness was 600 nm.

[0068] The passivation layer is formed on the surface of the three-dimensional perovskite layer. The specific steps include: using a spin coating method to form a passivation liquid film on the surface of the three-dimensional perovskite layer with a passivation solution, the rotation speed is 4000 r / min; the passivation liquid film is annealed at a temperature of 90℃ for 7 min to obtain a passivation layer with a thickness of 9 nm.

[0069] A perovskite solar cell was obtained by sequentially depositing a 20 nm thick PCBM layer, a 10 nm thick BCP layer, and a 120 nm thick second electrode layer on the surface of the passivation layer using a vacuum evaporation process. The material of the second electrode layer was silver.

[0070] The photoelectric conversion efficiency of the prepared perovskite solar cell was tested, and the initial efficiency was 21.2%, the open-circuit voltage was 1.18V, and the short-circuit current density was 23.38mA / cm². 2 The fill factor was 76.84%; the prepared perovskite solar cell maintained 96% of its initial efficiency after operating at 85℃ and 85% RH for 1800 h.

[0071] Example 3

[0072] This embodiment provides a method for fabricating a perovskite solar cell, including the following steps:

[0073] Prepare a passivation solution. The solutes in the passivation solution include phenethylamine hydroiodide and tenofovir, with a molar ratio of phenethylamine hydroiodide to tenofovir of 2.4. The solvent is isopropanol, and the concentration of the solutes is 0.20 mg / ml.

[0074] A copper indium gallium selenide (CIGS) thin-film solar cell is provided, wherein a first electrode layer is formed on the electrode surface of the CIGS thin-film solar cell using a physical vapor deposition (PVD) process. The material of the first electrode layer is ITO and the thickness is 100 nm.

[0075] A hole transport layer was formed on the surface of the first electrode layer by spin coating. The hole transport layer was made of poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA) and had a thickness of 10 nm.

[0076] A three-dimensional perovskite layer was formed on the surface of the hole transport layer using a spin-coating method. The material of the three-dimensional perovskite layer was Cs. 0.15 FA 0.85 PbI 2.4 Br 0.6 The thickness is 640nm;

[0077] The passivation layer is formed on the surface of the three-dimensional perovskite layer. The specific steps include: using a spin coating method to form a passivation liquid film on the surface of the three-dimensional perovskite layer with a passivation solution, the rotation speed is 5000 r / min; the passivation liquid film is annealed at a temperature of 70℃ for 9 min to obtain a passivation layer with a thickness of 8 nm.

[0078] A 30 nm thick C layer was sequentially deposited on the passivation layer surface using a vacuum evaporation process. 60 The perovskite / copper indium gallium selenide (CIGS) tandem solar cell consists of a 10nm thick BCP layer and a 120nm thick second electrode layer, with the second electrode layer made of silver.

[0079] The photoelectric conversion efficiency of the prepared perovskite / copper indium gallium selenide tandem solar cell was tested, and the initial efficiency was 21.3%.

[0080] Example 4

[0081] This embodiment provides a method for fabricating a perovskite solar cell, including the following steps:

[0082] Prepare a passivation solution. The solutes in the passivation solution include methylthiophene hydroiodate and 3-(1-pyridyl)propanesulfonate. The molar ratio of methylthiophene hydroiodate to 3-(1-pyridyl)propanesulfonate is 3.6. The solvent is isopropanol, and the concentration of the solute is 0.25 mg / ml.

[0083] A heterojunction solar cell is provided, wherein a first electrode layer is formed on the electrode surface of the heterojunction solar cell using a physical vapor deposition (PVD) process. The material of the first electrode layer is ITO and the thickness is 100 nm.

[0084] A hole transport layer was formed on the surface of the first electrode layer by spin coating. The material of the hole transport layer was [4-(3,6-dimethyl-9H-carbazole-9-yl)butyl]phosphonic acid (Me-4PACZ), and the thickness was 12 nm.

[0085] A three-dimensional perovskite layer was formed on the surface of the hole transport layer using a spin-coating method. The material of the three-dimensional perovskite layer was Cs. 0.12 FA 0.88 PbI 2.7 Br 0.3 The thickness is 680nm;

[0086] The passivation layer is formed on the surface of the three-dimensional perovskite layer. The specific steps include: using spin coating to form a passivation liquid film on the surface of the three-dimensional perovskite layer with a passivation solution, the rotation speed is 4000 r / min; the passivation liquid film is annealed at a temperature of 90℃ for 7 min to obtain a passivation layer with a thickness of 12 nm.

[0087] A 20 nm thick PCBM layer, a 10 nm thick BCP layer, and a 120 nm thick second electrode layer were sequentially deposited on the surface of the passivation layer using a vacuum evaporation process. The material of the second electrode layer was silver, thus obtaining a perovskite / heterojunction tandem solar cell.

[0088] The photoelectric conversion efficiency of the prepared perovskite / heterojunction tandem solar cell was tested, and the initial efficiency was 26.4%. After running at 85℃ and RH85% for 3000h, the prepared perovskite / heterojunction tandem solar cell maintained 96% of the initial efficiency.

[0089] Example 5

[0090] This embodiment provides a method for fabricating a perovskite solar cell, including the following steps:

[0091] A passivation solution was prepared, the solutes of which included methylpyridine hydroiodate and 2-pyridyltrifluoromethoxybenzamine, the molar ratio of methylpyridine hydroiodate to 2-pyridyltrifluoromethoxybenzamine was 8.5, the solvent was isopropanol, and the concentration of the solute was 0.15 mg / ml.

[0092] A gallium arsenide thin-film solar cell is provided, wherein a first electrode layer is formed on the electrode surface of the gallium arsenide thin-film solar cell using a physical vapor deposition (PVD) process. The material of the first electrode layer is ITO and the thickness is 100 nm.

[0093] A hole transport layer was formed on the surface of the first electrode layer by spin coating. The material of the hole transport layer was [4-(3,6-dimethyl-9H-carbazole-9-yl)butyl]phosphonic acid (Me-4PACZ), and the thickness was 10 nm.

[0094] A three-dimensional perovskite layer was formed on the surface of the hole transport layer using a spin-coating method. The material of the three-dimensional perovskite layer was Cs. 0.14 FA 0.86 PbI 2.7 Br 0.3 The thickness is 650nm;

[0095] The passivation layer is formed on the surface of the three-dimensional perovskite layer. The specific steps include: using spin coating to form a passivation liquid film on the surface of the three-dimensional perovskite layer with a passivation solution, the rotation speed is 5000 r / min; the passivation liquid film is annealed at a temperature of 100℃ for 6 min to obtain a passivation layer with a thickness of 8 nm.

[0096] A 20 nm thick C layer was sequentially deposited on the passivation layer surface using a vacuum evaporation process. 60 The perovskite / gallium arsenide tandem solar cell consists of a 15nm thick SnO2 layer and a 120nm thick second electrode layer, with the second electrode layer made of silver.

[0097] The photoelectric conversion efficiency of the prepared perovskite / gallium arsenide tandem solar cell was tested, and the initial efficiency was 18.2%. After running at 85℃ and RH85% for 3000 hours, the prepared perovskite / gallium arsenide tandem solar cell maintained 98% of the initial efficiency.

[0098] Comparative Example 1

[0099] This comparative example provides a method for fabricating a perovskite solar cell, which differs from the method for fabricating a perovskite solar cell provided in Example 1 in that: after forming a three-dimensional perovskite layer, this comparative example does not form a passivation layer, but directly forms a hole transport layer.

[0100] The photoelectric conversion efficiency of the prepared perovskite solar cell was tested, showing an initial efficiency of 18.57%, an open-circuit voltage of 1.05 V, and a short-circuit current density of 23.42 mA / cm². 2 The fill factor was 75.52%; the prepared perovskite solar cell maintained 92% of its initial efficiency after operating for 1200 h at 85℃ and 85% RH.

[0101] Comparative Example 2

[0102] 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 the passivation solution used in this comparative example has oleylamine hydroiodide as the solute.

[0103] The photoelectric conversion efficiency of the prepared perovskite solar cell was tested, showing an initial efficiency of 21.01%, an open-circuit voltage of 1.17 V, and a short-circuit current density of 23.32 mA / cm². 2The fill factor was 77.02%; the prepared perovskite solar cell maintained 90% of its initial efficiency after operating for 1200 h at 85℃ and 85% RH.

[0104] Comparative Example 3

[0105] 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 the passivation solution used in this comparative example has 2-quinoxaloline carboxylic acid as the solute.

[0106] The photoelectric conversion efficiency of the prepared perovskite solar cell was tested, and the initial efficiency was 21.30%, the open-circuit voltage was 1.16V, and the short-circuit current density was 23.85mA / cm². 2 The fill factor was 77.11%; the prepared perovskite solar cell maintained 90% of its initial efficiency after operating for 1200 h at 85℃ and 85% RH.

[0107] Comparative Example 4

[0108] 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 2 in that the passivation solution used in this comparative example has a solute of n-octylamine hydroiodate.

[0109] The photoelectric conversion efficiency of the prepared perovskite solar cell was tested, and the initial efficiency was 20.2%. After operating at 85℃ and RH85% for 1200 h, the prepared perovskite solar cell maintained 92% of the initial efficiency.

[0110] Comparative Example 5

[0111] 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 2 in that the passivation solution used in this comparative example has bis(trifluoromethanesulfonyl)imide as the solute.

[0112] The photoelectric conversion efficiency of the prepared perovskite solar cell was tested, and the initial efficiency was 20.7%. After operating at 85℃ and RH 85% for 1200 h, the prepared perovskite solar cell maintained 91% of the initial efficiency.

[0113] As can be seen from the comparison between Example 1 and Comparative Examples 1-3, and between Example 2 and Comparative Examples 4-5, compared with no passivation layer or the passivation layer being made of only the first passivation material or the second passivation material, this application uses both the first passivation material and the second passivation material to prepare the passivation layer, which effectively increases the short-circuit current density, open-circuit voltage and fill factor of the perovskite solar cell, thereby effectively improving the photoelectric conversion performance of the perovskite solar cell.

[0114] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A perovskite solar cell, characterized in that, The device comprises a substrate, a first electrode layer, a first carrier transport layer, a three-dimensional perovskite layer, a passivation layer, and a second carrier transport layer, which are stacked sequentially. The passivation layer is in contact with the three-dimensional perovskite layer and the second carrier transport layer. The passivation layer comprises a uniformly mixed first passivation material and a second passivation material. The first passivation material is at least one of the following: hexylamine hydroiodate, octylamine hydroiodate, oleylamine hydroiodate, naphthylamine hydroiodate, methylpyridine hydroiodate, methylimidazolium hydroiodate, methylcarbazole hydroiodate, and methylthiophene hydroiodate. The second passivation material is at least one of the following: bis(trifluoromethanesulfonyl)imide, 2-pyridyltrifluoromethoxybenzylimide, (5-mercapto-1,3,4-thiadiazol-2-ylthio)acetic acid, 3-(1-naphthyl)-L-alanine hydrochloride, tenofovir, 9-[2-(diethoxyphosphonomethoxy)ethyl]adenine, and adenosine phosphate.

2. The perovskite solar cell according to claim 1, characterized in that, The molar ratio of the first passivating material to the second passivating material is 2-300.

3. The perovskite solar cell according to claim 2, characterized in that, The molar ratio of the first passivating material to the second passivating material is 2-50.

4. The perovskite solar cell according to claim 1 or 2, characterized in that, The thickness of the passivation layer is 1nm-30nm.

5. The perovskite solar cell according to claim 4, characterized in that, The thickness of the passivation layer is 5nm-10nm.

6. The perovskite solar cell according to claim 1 or 2, characterized in that, The substrate includes glass, flexible substrate, heterojunction cell, crystalline silicon cell, or thin-film solar cell.

7. The method for preparing a perovskite solar cell according to any one of claims 1 to 6, characterized in that, include: A first electrode layer, a first carrier transport layer, a three-dimensional perovskite layer, a passivation layer, and a second carrier transport layer are sequentially formed on one side surface of a substrate. The substrate, the first electrode layer, the first carrier transport layer, the three-dimensional perovskite layer, the passivation layer, and the second carrier transport layer are stacked sequentially, and the passivation layer is in contact with the three-dimensional perovskite layer and the second carrier transport layer. The passivation layer includes a uniformly mixed first passivation material and a second passivation material. The first passivation material is an organic halide salt, and the second passivation material includes at least one of amino, carboxyl, phosphonoyl, and sulfonic acid groups.

8. The method for preparing a perovskite solar cell according to claim 7, characterized in that, The steps for forming the passivation layer include: A passivation solution is prepared, wherein the solute of the passivation solution includes a first passivation material and a second passivation material; The passivation solution is used to form a passivation liquid film on the surface of the three-dimensional perovskite layer away from the first carrier transport layer; The passivation liquid film is annealed.

9. The method for preparing a perovskite solar cell according to claim 8, characterized in that, The annealing temperature is 60℃-120℃, and the annealing time is 5min-10min.

10. The method for preparing a perovskite solar cell according to claim 8, characterized in that, The concentration of the solute in the passivation solution is 0.05 mg / ml to 0.35 mg / ml.

11. The method for preparing a perovskite solar cell according to claim 10, characterized in that, The passivation solution contains at least one of methanol and isopropanol as its solvent.

12. The method for preparing a perovskite solar cell according to claim 8, characterized in that, The passivation liquid film is formed on the surface of the three-dimensional perovskite layer using a spin coating method.

13. The method for preparing a perovskite solar cell according to claim 12, characterized in that, The spin coating speed is 2000 r / min-5000 r / min.

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