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 perovskite thin film absorption layer, a passivation layer and a hole transport layer which are stacked in sequence; and the preparation raw material of the passivation layer and / or the hole transport layer comprises an arylamine metal salt, the arylamine metal salt contains an amino group with a functionality of no less than 2. The application provides a hole transport layer material with high conductivity, high stability, few defects and adjustable energy level, the hole transport layer containing the arylamine metal salt is obtained through deposition, and the arylamine metal salt in the hole transport layer and the arylamine metal salt in the interface passivation layer have a synergistic effect, thereby improving the photoelectric performance of the perovskite solar cell.

Description

Technical Field

[0001] This invention belongs to the technical field of perovskite solar cell materials, specifically relating to a perovskite solar cell and its preparation method. Background Technology

[0002] Solar cells, as an energy storage device that converts solar energy into electrical energy, have the potential to replace other non-renewable energy sources such as coal, both from the perspective of photovoltaic technology development and economic feasibility.

[0003] Solar cells have undergone three generations of development. The first generation of photovoltaic cells, represented by silicon-based solar cells, suffered from drawbacks such as high power generation costs, high energy consumption, and fixed module positions. The second generation of thin-film solar cells, represented by copper indium gallium selenide and cadmium telluride, suffered from high toxicity and extremely limited reserves of component elements. Against this backdrop, the third generation of solar cells emerged, which combines advantages such as simple manufacturing processes, low cost, and flexible fabrication. These include quantum dot solar cells, dye-sensitized solar cells, and perovskite solar cells (PSCs).

[0004] Perovskite solar cells have attracted increasing attention due to their excellent photoelectric performance, solution processing, and low cost. Their photoelectric efficiency has also rapidly increased from the initial 3.8% to over 25%. The continuous improvement in efficiency and stability has provided a solid foundation for the further commercial application of PSCs in the future.

[0005] However, the organic components of perovskite have drawbacks such as volatility, low thermal stability, and dislocations and fractures in the perovskite lattice at grain boundaries and surfaces, leading to numerous defects during the fabrication of perovskite thin films. These defects form carrier trapping centers in the band gap, causing carrier recombination losses. Simultaneously, the interfaces in perovskite solar cells regulate photoelectric processes such as carrier extraction, transport, and collection, and are also crucial sites for carrier recombination.

[0006] Therefore, in order to obtain high-efficiency and stable perovskite solar cells, it is particularly important to passivate the defects of the perovskite layer and regulate its interface energy level. Summary of the Invention

[0007] To address the shortcomings of existing technologies, the present invention aims to provide a perovskite solar cell and its fabrication method. This invention provides a hole transport layer material with high conductivity, high stability, few defects, and tunable energy levels. The hole transport layer, containing arylamine metal salts, is deposited and exhibits a synergistic effect with an interface passivation layer containing arylamine metal salts, jointly enhancing the photoelectric performance of the perovskite solar cell.

[0008] To achieve this objective, the present invention adopts the following technical solution:

[0009] In a first aspect, the present invention provides a perovskite solar cell, the perovskite solar cell comprising a perovskite thin film absorber layer, a passivation layer and a hole transport layer stacked sequentially.

[0010] The raw materials for preparing the passivation layer and / or hole transport layer include arylamine metal salts, wherein the arylamine metal salts contain amino groups with a functionality of not less than two.

[0011] In this invention, the perovskite solar cell generally further includes a back electrode, an electron transport layer, and a substrate layer. The electron transport layer typically covers the surface of the perovskite thin-film absorber layer away from the hole transport layer. A passivation layer may exist between the electron transport layer and the perovskite thin-film absorber layer. The positions of the back electrode and the hole transport layer differ in conventional and inverted perovskite solar cells, and this invention does not limit their positions.

[0012] It should be noted that the technical solution in this invention can be applied to both conventional perovskite solar cells and inverted perovskite solar cells.

[0013] This invention effectively modulates the high conductivity, interfacial energy levels, and work function of the hole transport layer by doping it with arylamine metal salts. This not only promotes the energy level arrangement at the interface between the perovskite thin film absorber layer and the hole transport layer but also enhances hole extraction efficiency and significantly suppresses interfacial recombination. Furthermore, the strong electronic interaction between the arylamine metal salt-passivated hole transport layer and the perovskite thin film absorber layer further passivates defects in the absorber layer and enhances its crystallinity, thereby increasing grain size. Simultaneously, the amino groups in the arylamine metal salt structure neutralize free iodoformamide (FAI) in the precursor and form an intermediate structure, thus achieving a high-efficiency perovskite solar cell.

[0014] Preferably, the arylamine metal salt includes any one or a combination of at least two of the following: copper tetrahydrochloride of 1,2,4,5-phenyltetramine tetrahydrochloride, silver tetrahydrochloride of 1,2,4,5-phenyltetramine tetrahydrochloride, lithium tetrahydrochloride of 1,2,4,5-phenyltetramine tetrahydrochloride, or magnesium tetrahydrochloride of 1,2,4,5-phenyltetramine tetrahydrochloride. For the sake of brevity, all combinations within the above range will not be listed individually.

[0015] In this invention, the metal ions contained in the aforementioned phenyltetramine tetrahydrochloride metal salts can modulate the work function of the hole transport layer. The doping of these metal ions not only occupies defect sites, thereby improving the crystal quality and mobility of the thin film, but also replaces the Ni lattice. 2+ The position of the electron acceptor increases the hole concentration. And intrinsic NiO x Compared to hole transport layers, the doped hole transport layer exhibits higher conductivity and stronger hole extraction capability. The corresponding amino groups passivate Lewis acid defects in the perovskite through coordination bonds, neutralize free FAI in the precursor, and form an intermediate structure, thereby constructing a high-efficiency perovskite solar cell system. Therefore, the aforementioned phenyltetramine tetrahydrochloride metal salts can be used to fabricate high-efficiency and highly stable perovskite solar cells through the synergistic effect of defect passivation and energy level modulation.

[0016] Preferably, the preparation method of the arylamine metal salt includes the following steps:

[0017] (1) Mix metal chloride, acetate and water to obtain a salt solution;

[0018] (2) Mix arylamine hydrochloride and the first solvent to obtain an arylamine hydrochloride solution;

[0019] (3) Add the salt solution obtained in step (1) dropwise to the arylamine hydrochloride solution in step (2) to obtain a mixed solution;

[0020] (4) Concentrated ammonia water is diffused into the mixed solution by evaporation, and the arylamine metal salt is obtained after the reaction.

[0021] In this invention, the salt solution in step (3) needs to be slowly added dropwise to the arylamine hydrochloride solution in step (2); the concentrated ammonia also needs to be slowly evaporated and diffused into the mixed solution.

[0022] In this invention, highly crystalline arylamine metal salts can be synthesized by using a gas-phase diffusion method.

[0023] Preferably, the metal chloride salt in step (1) includes any one or a combination of at least two of copper chloride, silver chloride, lithium chloride or magnesium chloride. For example, it can be copper chloride, silver chloride, lithium chloride or magnesium chloride. For the sake of brevity, the combinations within the above range will not be listed one by one.

[0024] Preferably, the acetate in step (1) includes, but is not limited to, sodium acetate.

[0025] Preferably, the molar ratio of the acetate and the metal chloride in step (1) is 0 to 1. It should be noted that the molar ratio is not zero, for example, it can be 0.2, 0.5, 0.8 or 1.

[0026] Preferably, the first solvent in step (2) includes, but is not limited to, ethyl acetate.

[0027] Preferably, the concentration of the arylamine hydrochloride solution in step (2) is 0-0.1 mol / L. It should be noted that the molar concentration of the arylamine hydrochloride is not zero, and can be, for example, 0.02 mol / L, 0.05 mol / L, 0.07 mol / L, 0.075 mol / L, 0.08 mol / L, or 0.1 mol / L.

[0028] In this invention, by adjusting the concentration of the arylamine hydrochloride solution in step (2), the metal ions can be completely combined with the arylamine hydrochloride through coordination bonds to form an arylamine metal salt.

[0029] Preferably, the reaction time in step (4) is 12 to 24 hours, for example, 12 hours, 18 hours, 20 hours, 22 hours, or 24 hours.

[0030] In a second aspect, the present invention provides a method for preparing a perovskite solar cell according to the first aspect, the method comprising the following steps:

[0031] A hole transport layer is formed on the surface of the basal layer;

[0032] A passivation layer precursor solution is coated on the surface of the hole transport layer to form a passivation layer.

[0033] The passivation layer precursor solution and / or the hole transport layer contain an arylamine metal salt, wherein the arylamine metal salt contains an amino group with a functionality of not less than two.

[0034] In this invention, the hole transport layer can be deposited by electron beam evaporation technology, which has the advantages of high efficiency, high beam current density, fast evaporation rate, high purity and good quality of the produced film, and accurate control of thickness.

[0035] In this invention, the coating methods include, but are not limited to, blade coating, spray coating, or spin coating.

[0036] In this invention, the method for preparing the perovskite solar cell further includes:

[0037] A perovskite thin film absorption layer is coated on the surface of the passivation layer;

[0038] An electron transport layer is coated on the surface of the perovskite thin film absorber layer;

[0039] The back electrode is deposited on the surface of the electron transport layer to obtain the perovskite solar cell.

[0040] It should be noted that the preparation method of the perovskite thin film absorber layer is exemplarily as follows: MA 0.7 FA 0.3 PbI3 perovskite film precursor solution was coated onto the surface of the passivation layer, and then thermally annealed at 100-120℃ for 10-30 min to form a perovskite film absorption layer.

[0041] In this invention, the concentration of the perovskite thin film precursor solution is 1 to 2 mol / L, for example, it can be 1 mol / L, 1.2 mol / L, 1.5 mol / L, 1.8 mol / L, or 2 mol / L.

[0042] In this invention, the annealing temperature of the perovskite thin film absorber layer is 100-120°C, for example, 100°C, 105°C, 108°C, 110°C, 112°C, 115°C, or 120°C, and the time is 10-30 min, for example, 10 min, 15 min, 20 min, 25 min, or 30 min.

[0043] An exemplary method for preparing the electron transport layer is as follows: In a vacuum degree less than 10... -4 Under the condition of Pa, by vacuum evaporation, the perovskite thin film absorber layer surface is sequentially coated with the following... and rate of deposition C 60 Together with bathocuproine (BCP), it forms an electron transport layer containing carbon and tin layers;

[0044] An exemplary method for preparing the back electrode is as follows: In a vacuum degree less than 10... -4 Pa and evaporation rate are Under certain conditions, a back electrode is deposited on the surface of the electron transport layer by vacuum evaporation.

[0045] This invention provides another method for perovskite solar cells, the method comprising the following steps:

[0046] A passivation layer precursor solution is coated on the surface of the perovskite thin film absorber layer to form a passivation layer.

[0047] A hole transport layer is deposited on the surface of the passivation layer;

[0048] The passivation layer precursor solution and / or the hole transport layer contain an arylamine metal salt, wherein the arylamine metal salt contains an amino group with a functionality of not less than two.

[0049] In this invention, the other method for preparing a perovskite solar cell further includes:

[0050] Deposit an electron transport layer on the surface of the back electrode;

[0051] A perovskite thin film absorption layer is coated on the surface of the electron transport layer;

[0052] A base layer is formed on the surface of the hole transport layer.

[0053] It should be noted that the preparation method of the perovskite thin film absorber layer is exemplarily as follows: MA 0.7 FA 0.3 PbI3 perovskite film precursor solution was coated onto the surface of the passivation layer and then thermally annealed at 100-120℃ for 10-30 min to form a perovskite film absorption layer.

[0054] In this invention, the concentration of the perovskite thin film precursor solution is 1 to 2 mol / L, for example, it can be 1 mol / L, 1.2 mol / L, 1.5 mol / L, 1.8 mol / L, or 2 mol / L.

[0055] In this invention, the annealing temperature of the perovskite thin film absorber layer is 100-120°C, for example, 100°C, 105°C, 108°C, 110°C, 112°C, 115°C, or 120°C, and the time is 10-30 min, for example, 10 min, 15 min, 20 min, 25 min, or 30 min.

[0056] An exemplary method for preparing the electron transport layer is as follows: In a vacuum degree less than 10... -4 Under the condition of Pa, by vacuum evaporation, the perovskite thin film absorber layer surface is sequentially coated with the following... and rate of deposition C 60 Together with bathocuproine (BCP), it forms an electron transport layer containing carbon and tin layers;

[0057] An exemplary method for preparing the back electrode is as follows: In a vacuum degree less than 10... -4 Pa and evaporation rate are Under certain conditions, a back electrode is deposited on the surface of the electron transport layer by vacuum evaporation.

[0058] The substrate layer includes, but is not limited to, conductive glass.

[0059] Preferably, the mass percentage of arylamine metal salt in the hole transport layer is 0-5%, for example, it can be 0.1%, 1%, 2%, 3%, 4%, or 5%. It should be noted that the mass percentage of arylamine metal salt is not 0.

[0060] In this invention, by controlling the mass percentage of arylamine metal salt in the hole transport layer, the work function of the hole transport layer can be regulated. The doped metal ions can also occupy defect sites. If the content is too low, it will not be able to occupy all the defect sites, so that the defects still exist; otherwise, it will have a greater impact on the work function, causing energy level mismatch.

[0061] Preferably, the mass percentage of arylamine metal salt in the passivation layer precursor solution is 0-5%, for example, it can be 0.1%, 1%, 2%, 3%, 4%, or 5%. It should be noted that the mass percentage of arylamine metal salt is not 0.

[0062] Preferably, the passivation layer precursor solution contains N,N-dimethylformamide.

[0063] Preferably, the concentration of the passivation layer precursor solution is 0 to 1 mg / mL. It should be noted that the concentration of the passivation layer precursor solution is not zero, and can be, for example, 0.1 mg / mL, 0.2 mg / mL, 0.5 mg / mL, 0.8 mg / mL, or 1 mg / mL.

[0064] In this invention, by controlling the concentration of the passivation layer precursor solution, the amino groups contained therein passivate Lewis acid defects in the perovskite through coordination bonds, and can also neutralize free FAI in the precursor and form an intermediate structure; if the concentration is too low, it will not have a passivation effect, while if it is too high, it will induce a change in the work function of the perovskite surface, exacerbating the instability of the perovskite solar cell.

[0065] Preferably, the thickness of the passivation layer is 1-10nm, for example, it can be 1nm, 2nm, 3nm, 4nm, 5nm, 6nm, 7nm, 8nm, 9nm, or 10nm.

[0066] Preferably, the thickness of the hole transport layer is 10-20nm, for example, it can be 10nm, 12nm, 13nm, 14nm, 15nm, 16nm, 17nm, 18nm, 19nm, or 20nm.

[0067] Compared with the prior art, the present invention has the following beneficial effects:

[0068] This invention effectively modulates the high conductivity, interfacial energy levels, and work function of the hole transport layer by doping it with arylamine metal salts. This not only promotes the energy level arrangement at the interface between the perovskite thin film absorber layer and the hole transport layer but also enhances hole extraction efficiency and significantly suppresses interfacial recombination. Furthermore, the strong electronic interaction between the arylamine metal salt-passivated hole transport layer and the perovskite thin film absorber layer further passivates defects in the absorber layer and enhances its crystallinity, thereby increasing grain size. Simultaneously, the amino groups in the arylamine metal salt structure neutralize free FAI in the precursor and form an intermediate structure, thus achieving a high-efficiency perovskite solar cell. Attached Figure Description

[0069] Figure 1 The diagram shows the structure of the perovskite solar cell provided in Example 1, where 1-back electrode; 2-electron transport layer; 3-perovskite thin film absorber layer; 4-passivation layer; 5-hole transport layer; 6-substrate layer;

[0070] Figure 2 Light conversion efficiency performance diagrams provided for Examples 1-5 and Comparative Examples 1-3;

[0071] Figure 3 Photostable diagrams provided for Examples 1-5 and Comparative Examples 1-3;

[0072] Figure 4 High humidity and high thermal stability diagrams provided for Examples 1-5 and Comparative Examples 1-3. Detailed Implementation

[0073] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be considered as specific limitations thereof.

[0074] Example 1

[0075] This embodiment provides a perovskite solar cell, which includes a back electrode (80 nm thick), an electron transport layer (a 20 nm thick carbon layer and a 10 nm thick tin layer), a perovskite thin film absorber layer (400 nm thick), a passivation layer (2 nm thick), a hole transport layer (15 nm thick), and a substrate layer (500 nm thick) stacked sequentially. The passivation layer and the hole transport layer are both prepared using copper 1,2,4,5-phenyltetramine tetrahydrochloride as raw materials.

[0076] The preparation method of the 1,2,4,5-phenyltetramine tetracopper hydrochloride is as follows:

[0077] (1) In a petri dish, dissolve 1 mmol of copper chloride and 0.5 mmol of sodium acetate in 75 mL of water to obtain a salt solution;

[0078] (2) Dissolve 1.5 mmol of 1,2,4,5-phenyltetramine tetrahydrochloride (BTA·4HCl) in 20 mL of ethyl acetate to obtain a 1,2,4,5-phenyltetramine tetrahydrochloride solution.

[0079] (3) Slowly add the salt solution from step 1 to the 1,2,4,5-phenyltetramine tetrahydrochloride solution from step (2) to obtain a mixed solution;

[0080] (4) Add concentrated ammonia to another petri dish, and place the petri dish containing concentrated ammonia and the mixed solution obtained in step (3) into a beaker. Cover the beaker and allow the concentrated ammonia to slowly evaporate and diffuse into the mixed solution. After reacting for 24 hours, 1,2,4,5-phenyltetramine tetracopper hydrochloride (Cu-BTA) is obtained. The corresponding reaction equation is shown below.

[0081]

[0082] This embodiment also provides a perovskite solar cell, such as Figure 1 As shown, the preparation method is as follows:

[0083] (1) Nickel oxide (NiO) with a doping content of 3 wt.% Cu-BTA was deposited on the surface of a conductive substrate (FTO glass) using electron beam evaporation technology. X This forms a hole transport layer;

[0084] (2) Cu-BTA is dissolved in N,N-dimethylformamide (DMF) to form a passivation layer precursor solution with a concentration of 0.5 mg / mL. The passivation layer precursor solution is then coated onto the surface of the hole transport layer to form an interface passivation layer.

[0085] (3) Add 1.5 mol / L MA 0.7 FA 0.3 PbI3 precursor solution was coated onto the surface of the passivation layer and then thermally annealed at 110℃ for 20 min to form a perovskite thin film absorption layer.

[0086] (4) When the vacuum degree is less than 10 -4 Under the condition of Pa, by vacuum evaporation, the perovskite thin film absorber layer surface is sequentially deposited according to the following... and rate of deposition C 60 Together with Bathocuproine, they form an electron transport layer containing carbon and tin layers;

[0087] (5) When the vacuum degree is less than 10-4 Pa and evaporation rate are Under certain conditions, the back electrode is deposited on the surface of the electron transport layer by vacuum evaporation to obtain the perovskite solar cell.

[0088] Example 2

[0089] The difference between this embodiment and Embodiment 1 is that, in the process of preparing perovskite solar cells, step (1) uses a co-evaporation method, and an evaporation boat is used to evaporate NiO. X Electron beam deposition of Cu-BTA was performed, with the deposition rate controlled to ensure that the Cu-BTA doping content in the hole transport layer was 3 wt.%, with the rest being the same as in Example 1.

[0090] Example 3

[0091] The difference between this embodiment and Embodiment 1 is that the raw materials for preparing the passivation layer and the hole transport layer both include silver 1,2,4,5-phenyltetramine tetrahydrochloride (Ag-BTA), and the corresponding reaction equations are shown below. In the process of preparing the perovskite solar cell, in step (1), nickel oxide doped with 3 wt.% Ag-BTA is evaporated using an electron beam to form the hole transport layer; in step (2), Ag-BTA is dissolved in N,N-dimethylformamide, and the rest is the same as in Embodiment 1.

[0092]

[0093] Example 4

[0094] The difference between this embodiment and Embodiment 1 is that the raw materials for preparing the passivation layer and the hole transport layer both include lithium 1,2,4,5-phenyltetramine tetrahydrochloride (Li-BTA), and the corresponding reaction equations are shown below. In the process of preparing the perovskite solar cell, in step (1), nickel oxide doped with 3 wt.% Li-BTA is evaporated using an electron beam to form the hole transport layer; in step (2), Li-BTA is dissolved in N,N-dimethylformamide, and the rest is the same as in Embodiment 1.

[0095]

[0096] Example 5

[0097] The difference between this embodiment and Example 1 is that the raw materials for preparing the passivation layer and the hole transport layer both include magnesium 1,2,4,5-phenyltetramine tetrahydrochloride (Mg-BTA), and the corresponding reaction equations are shown below. In the process of preparing the perovskite solar cell, in step (1), nickel oxide doped with 3 wt.% Mg-BTA is evaporated using an electron beam to form the hole transport layer; in step (2), Mg-BTA is dissolved in N,N-dimethylformamide, and the rest is the same as in Example 1.

[0098]

[0099] Example 6

[0100] This embodiment provides a perovskite solar cell, which includes a back electrode (80 nm thick), an electron transport layer (a 20 nm thick carbon layer and a 10 nm thick tin layer), a perovskite thin film absorber layer (400 nm thick), a passivation layer (2 nm thick), a hole transport layer (15 nm thick), and a substrate layer (500 nm thick) stacked sequentially. The passivation layer and the hole transport layer are both prepared using copper 1,2,4,5-phenyltetramine tetrahydrochloride as raw materials.

[0101] The preparation method of the 1,2,4,5-phenyltetramine tetracopper hydrochloride is as follows:

[0102] (1) In a petri dish, dissolve 1 mmol of copper chloride and 0.1 mmol of sodium acetate in 75 mL of water to obtain a salt solution;

[0103] (2) Dissolve 0.002 mmol of 1,2,4,5-phenyltetramine tetrahydrochloride (BTA·4HCl) in 20 mL of ethyl acetate to obtain a 1,2,4,5-phenyltetramine tetrahydrochloride solution;

[0104] (3) Slowly add the salt solution from step 1 to the 1,2,4,5-phenyltetramine tetrahydrochloride solution from step (2) to obtain a mixed solution;

[0105] (4) Add concentrated ammonia to another petri dish, and place the petri dish containing concentrated ammonia and the mixed solution obtained in step (3) into a beaker. Cover the beaker and allow the concentrated ammonia to slowly evaporate and diffuse into the mixed solution. After reacting for 12 hours, 1,2,4,5-phenyltetramine tetracopper hydrochloride (Cu-BTA) is obtained. The corresponding reaction equation is shown below.

[0106]

[0107] This embodiment also provides a perovskite solar cell, such as Figure 1 As shown, the preparation method is as follows:

[0108] (1) Nickel oxide (NiO) with a doping content of 0.5 wt.% Cu-BTA was deposited on the surface of a conductive substrate (FTO glass) using electron beam evaporation technology. X This forms a hole transport layer;

[0109] (2) Cu-BTA is dissolved in N,N-dimethylformamide (DMF) to form a passivation layer precursor solution with a concentration of 0.2 mg / mL. The passivation layer precursor solution is then coated onto the surface of the hole transport layer to form an interface passivation layer.

[0110] (3) Add 1.5 mol / L MA 0.7 FA 0.3 PbI3 precursor solution was coated onto the surface of the passivation layer and then thermally annealed at 110℃ for 20 min to form a perovskite thin film absorption layer.

[0111] (4) When the vacuum degree is less than 10 -4 Under the condition of Pa, by vacuum evaporation, the perovskite thin film absorber layer surface is sequentially deposited according to the following... and rate of deposition C 60 Together with Bathocuproine, they form an electron transport layer containing carbon and tin layers;

[0112] (5) When the vacuum degree is less than 10 -4 Pa and evaporation rate are Under certain conditions, the back electrode is deposited on the surface of the electron transport layer by vacuum evaporation to obtain the perovskite solar cell.

[0113] Example 7

[0114] This embodiment provides a perovskite solar cell, which includes a back electrode (80 nm thick), an electron transport layer (a 20 nm thick carbon layer and a 10 nm thick tin layer), a perovskite thin film absorber layer (400 nm thick), a passivation layer (2 nm thick), a hole transport layer (15 nm thick), and a substrate layer (500 nm thick) stacked sequentially. The passivation layer and the hole transport layer are both prepared using copper 1,2,4,5-phenyltetramine tetrahydrochloride as raw materials.

[0115] The preparation method of the 1,2,4,5-phenyltetramine tetracopper hydrochloride is as follows:

[0116] (1) In a petri dish, dissolve 1 mmol of copper chloride and 1 mmol of sodium acetate in 75 mL of water to obtain a salt solution;

[0117] (2) Dissolve 2 mmol of 1,2,4,5-phenyltetramine tetrahydrochloride (BTA·4HCl) in 20 mL of ethyl acetate to obtain a 1,2,4,5-phenyltetramine tetrahydrochloride solution.

[0118] (3) Slowly add the salt solution from step 1 to the 1,2,4,5-phenyltetramine tetrahydrochloride solution from step (2) to obtain a mixed solution;

[0119] (4) Add concentrated ammonia to another petri dish, and place the petri dish containing concentrated ammonia and the mixed solution obtained in step (3) into a beaker. Cover the beaker and allow the concentrated ammonia to slowly evaporate and diffuse into the mixed solution. After reacting for 24 hours, 1,2,4,5-phenyltetramine tetracopper hydrochloride (Cu-BTA) is obtained. The corresponding reaction equation is shown below.

[0120]

[0121] This embodiment also provides a perovskite solar cell, such as Figure 1 As shown, the preparation method is as follows:

[0122] (1) Nickel oxide (NiO) with a doping content of 5 wt.% Cu-BTA was deposited on the surface of a conductive substrate (FTO glass) using electron beam evaporation technology. X This forms a hole transport layer;

[0123] (2) Dissolve Cu-BTA in N,N-dimethylformamide (DMF) to form a passivation layer precursor solution with a concentration of 1 mg / mL. Then, apply the passivation layer precursor solution to the surface of the hole transport layer to form an interface passivation layer.

[0124] (3) Add 1.5 mol / L MA 0.7 FA 0.3 PbI3 precursor solution was coated onto the surface of the passivation layer and then thermally annealed at 110℃ for 20 min to form a perovskite thin film absorption layer.

[0125] (4) When the vacuum degree is less than 10 -4 Under the condition of Pa, by vacuum evaporation, the perovskite thin film absorber layer surface is sequentially deposited according to the following... and rate of deposition C 60 Together with Bathocuproine, they form an electron transport layer containing carbon and tin layers;

[0126] (5) When the vacuum degree is less than 10 -4 Pa and evaporation rate are Under certain conditions, the back electrode is deposited on the surface of the electron transport layer by vacuum evaporation to obtain the perovskite solar cell.

[0127] Example 8

[0128] The difference between this embodiment and Embodiment 1 is that the raw materials for preparing the passivation layer and the hole transport layer both include copper diphenylenediamine dihydrochloride, while the rest are the same as in Embodiment 1.

[0129] Comparative Example 1

[0130] The difference between this comparative example and Example 1 is that in the process of preparing perovskite solar cells, the pure nickel oxide hole transport layer evaporated by electron beam is used in step (1), and 1,2,4,5-phenyltetramine tetracopper hydrochloride is no longer doped. The rest is the same as in Example 1.

[0131] Comparative Example 2

[0132] The difference between this comparative example and Example 1 is that step (2) is no longer performed in the process of preparing perovskite solar cells, while the remaining steps are retained and are the same as in Example 1.

[0133] Comparative Example 3

[0134] The difference between this comparative example and Example 1 is that in the process of preparing perovskite solar cells, the pure nickel oxide hole transport layer evaporated by electron beam is used in step (1), and 1,2,4,5-phenyltetramine tetracopper hydrochloride is no longer doped. At the same time, the operation in step (2) is no longer performed. All other steps are the same as in Example 1.

[0135] Test conditions

[0136] The perovskite solar cells provided in Examples 1 to 8 and Comparative Examples 1 to 3 were subjected to performance testing, and the testing methods are as follows:

[0137] (1) Photoelectric conversion efficiency (PCE): The photoelectric conversion efficiency of the perovskite solar cell during the aging process is tested.

[0138] (2) Stability: The photoelectric conversion efficiency of the perovskite solar cell was characterized by aging under conditions of light stability (maximum output power under simulated sunlight) and high humidity and high thermal stability (85℃, 85%RH). The difference between the photoelectric conversion efficiency of the perovskite solar cell after aging for 1200h and that of the perovskite solar cell in the initial state was statistically analyzed.

[0139] The test results are shown in Table 1:

[0140] Table 1

[0141]

[0142] As can be seen from the data in Table 1, such as Figures 2-4As shown, the perovskite solar cell of the present invention has a light conversion efficiency of over 14% in the initial state, and after aging at 85℃ / 85%RH for 1200h, the light conversion efficiency is over 13%, and the absolute value of the PCE change rate after aging is within 4.29%, further demonstrating that the perovskite solar cell of the present invention has excellent electrical performance and stability.

[0143] Analysis of Comparative Examples 1-3 and Example 1 shows that the performance of Comparative Examples 1-3 is not as good as that of Example 1, which proves that the perovskite solar cell with arylamine metal salt doping and interface passivation layer in the hole transport layer has better performance. The example even achieved positive growth in light conversion efficiency after aging.

[0144] analyze Figure 2 It can be seen that the light conversion efficiency of the perovskite solar cells in the initial state of Comparative Examples 1-3 is not as good as that of the embodiments.

[0145] analyze Figure 3 and Figure 4 It can be seen that the light conversion efficiency of the perovskite solar cells described in each embodiment changes little with the extension of aging time, and the stability is high; while the light conversion efficiency of the perovskite solar cells described in Comparative Examples 1-3 changes much more with the extension of aging time, and the stability is poor.

[0146] Analysis of Example 8 and Example 1 shows that the performance of Example 8 is not as good as that of Example 1, proving that the perovskite battery with an amino group of not less than 2 in the arylamine metal salt has better performance.

[0147] The applicant declares that the present invention is illustrated by the above embodiments, but the present invention is not limited to the above process steps, that is, it does not mean that the present invention must rely on the above process steps to be implemented. Those skilled in the art should understand that any improvements to the present invention, equivalent substitutions of the raw materials used in the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A perovskite solar cell, characterized in that, The perovskite solar cell comprises a perovskite thin film absorber layer, a passivation layer, and a hole transport layer stacked sequentially. The raw materials for preparing the passivation layer and the hole transport layer include arylamine metal salts, wherein the arylamine metal salts contain amino groups with a functionality of not less than two.

2. The perovskite solar cell according to claim 1, characterized in that, The arylamine metal salt includes any one or a combination of at least two of the following: copper 1,2,4,5-phenyltetramine tetrahydrochloride, silver 1,2,4,5-phenyltetramine tetrahydrochloride, lithium 1,2,4,5-phenyltetramine tetrahydrochloride, or magnesium 1,2,4,5-phenyltetramine tetrahydrochloride.

3. The perovskite solar cell according to claim 1, characterized in that, The preparation method of the arylamine metal salt includes the following steps: (1) Mix metal chloride, acetate and water to obtain a salt solution; (2) Mix arylamine hydrochloride and the first solvent to obtain an arylamine hydrochloride solution; (3) Add the salt solution obtained in step (1) dropwise to the arylamine hydrochloride solution in step (2) to obtain a mixed solution; (4) Concentrated ammonia water is diffused into the mixed solution by evaporation, and the arylamine metal salt is obtained after the reaction.

4. The perovskite solar cell according to claim 3, characterized in that, The metal chloride salt mentioned in step (1) includes any one or a combination of at least two of copper chloride, silver chloride, lithium chloride, or magnesium chloride.

5. The perovskite solar cell according to claim 3, characterized in that, The acetate mentioned in step (1) includes sodium acetate.

6. The perovskite solar cell according to claim 3, characterized in that, The molar ratio of the acetate and the metal chloride in step (1) is 0 to 1, but does not include 0.

7. The perovskite solar cell according to claim 3, characterized in that, In step (2), the first solvent includes ethyl acetate.

8. The perovskite solar cell according to claim 3, characterized in that, The concentration of the arylamine hydrochloride solution in step (2) is 0 to 0.1 mol / L, but does not include 0 mol / L.

9. The perovskite solar cell according to claim 3, characterized in that, The reaction time in step (4) is 12 to 24 hours.

10. A method for preparing a perovskite solar cell according to any one of claims 1-9, characterized in that, The method includes the following steps: A hole transport layer is formed on the surface of the basal layer; A passivation layer precursor solution is coated on the surface of the hole transport layer to form a passivation layer. The passivation layer precursor solution and the hole transport layer contain arylamine metal salts, wherein the arylamine metal salts contain amino groups with a functionality of not less than two.

11. A method for preparing a perovskite solar cell according to any one of claims 1-9, characterized in that, The method includes the following steps: A passivation layer precursor solution is coated on the surface of the perovskite thin film absorber layer to form a passivation layer. A hole transport layer is deposited on the surface of the passivation layer; The passivation layer precursor solution and the hole transport layer contain arylamine metal salts, wherein the arylamine metal salts contain amino groups with a functionality of not less than two.

12. The method according to claim 10 or 11, characterized in that, The mass percentage of arylamine metal salt in the hole transport layer is 0-5%, but not 0%.

13. The method according to claim 10 or 11, characterized in that, The mass percentage of arylamine metal salt in the passivation layer precursor solution is 0-5%, but not 0%.

14. The method according to claim 10 or 11, characterized in that, The passivation layer precursor solution contains N,N-dimethylformamide.

15. The method according to claim 10 or 11, characterized in that, The concentration of the passivation layer precursor solution is 0 to 1 mg / mL, but does not include 0 mg / mL.

16. The method according to claim 10 or 11, characterized in that, The thickness of the passivation layer is 1-10 nm.

17. The method according to claim 10 or 11, characterized in that, The thickness of the hole transport layer is 10-20 nm.

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