Perovskite solar cell and preparation method thereof
By introducing a MOF material layer doped with metal R atoms into perovskite solar cells, the problem of poor conductivity between the electron transport layer and the perovskite absorber layer was solved, resulting in a significant improvement in cell efficiency.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2022-08-26
- Publication Date
- 2026-03-24
AI Technical Summary
In existing perovskite solar cells, the poor conductivity between the electron transport layer and the perovskite absorber layer leads to low cell efficiency.
A MOF material layer is set between the electron transport layer and the perovskite absorber layer. The MOF material layer is composed of MOF material doped with metal R atoms. The conductivity and energy band are controlled by the porous structure of the MOF material and the doped metal R atoms to improve conductivity.
It significantly improves the open-circuit voltage, current density, fill factor, and cell conversion efficiency of perovskite solar cells, thereby enhancing cell performance.
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Figure CN115425152B_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of perovskite solar cells, in particular to a perovskite solar cell and a preparation method thereof. BACKGROUND
[0002] Perovskite solar cells have attracted extensive attention due to their excellent photoelectric properties such as tunable band gap, high light absorption coefficient, long carrier lifetime and diffusion length, high defect tolerance, and low-cost low-temperature liquid-phase preparation method. However, how to design perovskite solar cells to improve cell efficiency has become a problem to be solved.
[0003] In the prior art, a perovskite solar cell generally comprises, from bottom to top, a transparent conductive layer, an electron transport layer, a perovskite absorption layer, a hole transport layer, and an electrode. However, the conductivity between the electron transport layer and the perovskite absorption layer is poor, resulting in low cell efficiency of the perovskite solar cell. SUMMARY
[0004] The present application provides a perovskite solar cell, which aims to solve the problem of poor conductivity between the electron transport layer and the perovskite absorption layer in the prior art perovskite solar cell, resulting in low cell efficiency.
[0005] The present application is implemented by providing a perovskite solar cell, comprising, from bottom to top, a transparent conductive layer, an electron transport layer, a perovskite absorption layer, a hole transport layer, and an electrode. The perovskite solar cell further comprises:
[0006] A MOF material layer is arranged between the electron transport layer and the perovskite absorption layer, and the MOF material layer is composed of a MOF material doped with metal R atoms. The structural formula of the MOF material is C8H 10 N4U 1-y R y ; U and R are one or more of Zn, Ni, Fe, Co, Cu, or rare earth metals, and U and R are different from each other, and the mass fraction of R is less than the mass fraction of U.
[0007] Preferably, the mass fraction of U is 15-40%, and the mass fraction of R is 0.5-10%.
[0008] Preferably, the doped metal R atoms are uniformly distributed in the framework of the MOF material, and the doped metal R atoms are chemically bonded to the non-metal of the MOF material.
[0009] Preferably, the framework of the MOF material is a dodecahedron structure, and the doped metal R atoms are distributed at each vertex position of the dodecahedron structure.
[0010] Preferably, the MOF material layer has a thickness of 0.3-5 um.
[0011] The application also provides a method for preparing a perovskite solar cell, comprising the following steps:
[0012] forming an electron transport layer on the transparent conductive layer;
[0013] forming a MOF material layer on the electron transport layer; the MOF material layer is composed of a MOF material doped with metal R atoms, and the MOF material has a structural formula of C8H 10 N4U 1-y R y ; U and R are one or more of Zn, Ni, Fe, Co, Cu or rare earth metals, and U and R are different from each other, and the mass fraction of R is less than that of U.
[0014] forming a perovskite absorption layer on the MOF material layer;
[0015] forming a hole transport layer on the perovskite absorption layer;
[0016] forming an electrode on the hole transport layer.
[0017] Preferably, the mass fraction of U is 15-40%, and the mass fraction of R is 0.5-10%.
[0018] Preferably, the step of forming a MOF material layer on the electron transport layer comprises:
[0019] Step A: dissolving a metal U salt solution and a metal R salt solution in a C solution, stirring uniformly, and then adding to a C solution containing a D solution to obtain a mixed solution, heating, cooling and filtering the mixed solution to obtain a MOF material doped with metal R atoms; the C solution is one or more of methanol, ethanol, isopropyl alcohol or acetone, and the D solution is one or more of dimethylimidazole, N,N-dimethylformamide and tris(2-benzimidazole methyl)amine;
[0020] Step B: mixing the MOF material doped with metal R atoms obtained in step A with an E solution to configure a precursor solution, spin coating the precursor solution on the electron transport layer and drying to form the MOF material layer; the E solution is one or more of DMF, DMSO, NMP and gamma-butyrolactone.
[0021] Preferably, the metal U salt solution is one or more of zinc nitrate, zinc sulfate or zinc chloride, and the metal R salt solution is one or more of nickel acetylacetone, nickel nitrate, nickel sulfate or nickel chloride.
[0022] Preferably, the ratio of the number of moles of metal U in the metal U salt solution to the number of moles of metal R in the metal R salt solution is 9-95.
[0023] Preferably, after the filtering of the MOF material doped with metal R atoms, the method further comprises:
[0024] The MOF material doped with metal R atoms is cleaned by a cleaning solution.
[0025] The perovskite solar cell provided by the present application sets a MOF material layer between the electron transport layer and the perovskite absorption layer, and the MOF material layer is composed of MOF material doped with metal R atoms. On the one hand, the MOF material has a porous and inter-granular gap structure, so the contact area of the MOF material layer with the perovskite absorption layer and the electron transport layer is larger, which is conducive to improving the electrical conductivity between the electron transport layer and the perovskite absorption layer. On the other hand, a small amount of metal R atoms is doped in the metal-organic framework structure of the MOF material, and the doped metal R atoms are used to regulate the electrical conductivity and energy band of the MOF material, which is conducive to matching the conduction band energy level of the MOF material with that of the perovskite, facilitating electron movement and improving the electrical conductivity between the electron transport layer and the perovskite absorption layer, thereby improving the cell efficiency of the perovskite solar cell. BRIEF DESCRIPTION OF DRAWINGS
[0026] Figure 1 FIG. 1 is a structural schematic diagram of a perovskite solar cell provided by an embodiment of the present application;
[0027] Figure 2 FIG. 2 is a flowchart of a perovskite solar cell preparation method provided by an embodiment of the present application. DETAILED DESCRIPTION
[0028] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application is further described in detail below in combination with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application, and are not used to limit the present application.
[0029] The perovskite solar cell provided by the embodiment of the present application sets a MOF material layer between the electron transport layer and the perovskite absorption layer, and the MOF material layer is composed of MOF material doped with metal R atoms. On the one hand, the MOF material has a porous and intergranular gap structure, so that the MOF material layer has a larger contact area with the perovskite absorption layer and the electron transport layer, which is conducive to improving the conductivity between the electron transport layer and the perovskite absorption layer. On the other hand, a small amount of metal R atoms is doped in the metal-organic framework structure of the MOF material, and the doped metal R atoms are used to regulate the conductivity and energy band of the MOF material, which is conducive to matching the conduction band energy level of the MOF material with that of the perovskite, and conducive to electron movement, thereby improving the conductivity between the electron transport layer and the perovskite absorption layer, and greatly improving the cell efficiency of the perovskite solar cell.
[0030] Please refer to Figure 1 The perovskite solar cell provided by the embodiment of the present application comprises, from bottom to top, a transparent conductive layer 1, an electron transport layer 2, a MOF material layer 3, a perovskite absorption layer 4, a hole transport layer 5 and an electrode 6. The MOF material layer is composed of MOF material doped with metal R atoms. The structural formula of the MOF material is C8H 10 N4U 1-y R y U and R are one or more of Zn, Ni, Fe, Co, Cu or rare earth metals, and U and R are different from each other, and the mass fraction of R is less than that of U.
[0031] In the embodiment of the present application, the specific structure of the transparent conductive layer 1 can comprise, from bottom to top, a transparent glass substrate and a transparent conductive film. The transparent glass substrate is used for transmitting sunlight, and the transparent conductive film is used for light transmission and conduction.
[0032] As an embodiment of the present application, the transparent conductive film can be any one of ITO film, FTO film, IWO film, IWO film and ICO film. In actual application, any one of ITO film, FTO film, IWO film, IWO film and ICO film can be selected.
[0033] In the embodiment of the present application, the MOF material layer 3 is arranged between the electron transport layer 2 and the perovskite absorption layer 4 of the perovskite solar cell, and the MOF material layer 3 is composed of MOF material doped with metal R atoms. On the one hand, the MOF material has a porous and inter-particle gap structure, so that the MOF material layer 3 has a larger contact area with the perovskite absorption layer 4 and the electron transport layer 2, which is conducive to improving the conductivity between the electron transport layer 2 and the perovskite absorption layer 4. On the other hand, since the mass fraction of R is less than the mass fraction of U, a small amount of metal R atoms is doped in the metal-organic framework structure of the MOF material, and the conductivity and energy band of the MOF material are adjusted by doping the metal R atoms, which is conducive to matching the conduction band of the MOF material with the conduction band of the perovskite, and conducive to electron movement, thereby improving the conductivity and greatly improving the cell efficiency of the perovskite solar cell.
[0034] As an embodiment of the present application, the material of the electron transport layer 2 can be at least one of TiO2, ZnO and SnO2. Preferably, the material of the electron transport layer 2 is TiO2.
[0035] In the embodiment of the present application, the perovskite absorption layer 4 can be made of pure organic perovskite or inorganic perovskite.
[0036] As a preferred embodiment of the present application, the perovskite absorption layer 4 is prepared by reacting perovskite crystals and MOF material doped with metal R atoms, the structural formula of the perovskite crystal is PbMAX3, X is one or more of F, Cl, Br and I; the structural formula of the MOF material doped with metal R atoms is C8H 10 N4U 1-y R y ; U and R are one or more of Zn, Ni, Fe, Co, Cu or rare earth metals, and U and R are different from each other, and the mass fraction of R is less than the mass fraction of U.
[0037] In the MOF material (C8H 10 N4U 1-y R y ), the metal U and the metal R form a metal-organic framework structure with non-metals, and the metal U and the metal R are uniformly doped in the metal-organic framework structure. U and R can be one or more of Zn, Ni, Fe, Co, Cu or rare earth metals, and U and R are different from each other. For example, U and R correspond to Zn and Ni respectively, i.e. Ni atoms are doped in the metal Zn-organic framework, and the structural formula of the MOF material doped with Ni atoms is C8H 10 N4Zn 1-y Ni y . The rare earth metal can be scandium (Sc), yttrium (Y), lanthanum (La) and the like.
[0038] In the embodiment of the present application, the MOF material layer 3 is arranged between the electron transport layer 2 and the perovskite absorption layer 4 of the perovskite solar cell, and the perovskite absorption layer 4 is prepared by the reaction of the perovskite crystal (PbMAX3) and the MOF material (C8H 10 N4U 1-y R y ) doped with metal R atoms; on the one hand, the perovskite crystal is uniformly combined with the framework of the MOF material, the framework of the MOF material can stabilize the perovskite crystal structure, and the MOF material can act as an electron donor to increase the conductivity of the entire perovskite absorption layer 4, which is conducive to the separation of photo-generated carriers and improves the efficiency of the perovskite solar cell; on the other hand, a small amount of metal R atoms is doped in the single metal U metal-organic framework structure of the traditional MOF material, so that the conductivity and energy band of the MOF material are regulated by doping the metal R atoms to promote the absorption of visible light and improve the efficiency of the perovskite solar cell; therefore, the MOF material layer 3 between the electron transport layer 2 and the perovskite absorption layer 4 and the perovskite absorption layer 4 prepared by the reaction of the perovskite crystal and the MOF material work together to improve the conductivity and further improve the efficiency of the cell.
[0039] In the embodiment of the present application, the metal U and the metal R are different from each other, that is, a small amount of metal R atoms different from the metal U is doped in the metal U-organic framework of the traditional MOF material, which can improve the band gap and improve the light absorption efficiency. For example, the metal U is Zn, and the metal R is one or more of Ni, Fe, Co, Cu or rare earth metal.
[0040] In the embodiment of the present application, the molar ratio of PbMAX3 to C8H 10 N4U 1-y R y of the perovskite absorption layer 4 is controlled to be 0.5-5 to ensure good light absorption and conductivity of the perovskite absorption layer 4.
[0041] In the embodiment, the perovskite crystal of the perovskite absorption layer 4 is coated inside the framework of the MOF material or attached to the surface of the framework of the MOF material, so that the perovskite crystal is uniformly combined with the framework of the MOF material, the pore structure of the MOF material is enriched, and the stability and conductivity of the perovskite absorption layer 4 are greatly improved compared with pure organic or inorganic perovskite.
[0042] As an embodiment of the present application, the mass fraction of U in the MOF material layer 3 is 15-40%, and the mass fraction of R in the MOF material layer 3 is 0.5-10%. Since the mass fraction of R is 0.5-10% and the mass fraction of U is 15-40%, only a small amount of metal R atoms are doped in the MOF material in the MOF material layer 3 to control the conductivity and energy band of the MOF material layer 3, promote the absorption of visible light, and ensure a low cost.
[0043] As an embodiment of the present application, the doped metal R atoms in the MOF material layer 3 are uniformly distributed in the framework of the MOF material, and the doped metal R atoms are chemically bonded to the non-metal of the MOF material. Among them, the MOF material (C8H 10 N4U 1-y R y ) forms a metal-organic framework structure with the metal U and the metal R, respectively, and the non-metal, which is conducive to improving the conductivity of the MOF material layer 3.
[0044] As an embodiment of the present application, the thickness of the MOF material layer 3 is 0.3-5um, which can ensure good conductivity of the MOF material layer 3 and ensure the absorption efficiency of sunlight of the perovskite solar cell.
[0045] As an embodiment of the present application, the material of the hole transport layer 5 can be any one of NiO X , CuSCN, CuI, V2O5, Cu2O.
[0046] As an embodiment of the present application, the material of the electrode 6 can be one of Au, Cu, and C.
[0047] In order to prove the technical effects achieved by the present application, two groups of perovskite solar cells were tested, wherein the control group used a conventional perovskite solar cell without a MOF material layer 3, and the experimental group used a perovskite solar cell with a MOF material layer 3 according to the present application. The data are shown in Table 1:
[0048] Table 1
[0049] Classification V oc (V) J sc (mA / cm -2 )]]> FF (%) PCE (%) Control group 1.05 24.0 81.5 20.5 Experimental group 1.08 24.5 82.5 21.8
[0050] Among them, Voc is the open circuit voltage; Jsc is the current density; FF is the fill factor; and PCE is the battery conversion efficiency.
[0051] From the experimental data in Table 1 above, it can be seen that compared with the conventional perovskite solar cell, the perovskite solar cell with the MOF material layer 3 according to the present application can significantly improve the open circuit voltage, current density, fill factor and battery conversion efficiency of the solar cell, greatly improving the battery performance.
[0052] Embodiment Two
[0053] For reference Figure 2 The application further provides a preparation method of the perovskite solar cell, for preparing the perovskite solar cell of Embodiment One, and the preparation method of the perovskite solar cell comprises the following steps:
[0054] Step S1, preparing an electron transport layer 2 on the transparent conductive layer 1;
[0055] In this embodiment, the electron transport layer 2 is prepared on the transparent conductive layer 1 by using a conventional preparation process of the perovskite solar cell, and specifically can comprise:
[0056] The TiO2 precursor solution is coated on the transparent conductive layer 1 and dried to obtain the electron transport layer 2. The thickness of the electron transport layer 2 is 98-100 nm, and the annealing temperature is 150℃.
[0057] Step S2, preparing a MOF material layer 3 on the electron transport layer 2; the MOF material layer 3 is made of a MOF material doped with metal R atoms, and the structural formula of the MOF material is C8H 10 N4U 1-y R y ; U and R are one or more of Zn, Ni, Fe, Co, Cu or rare earth metals, and U and R are different from each other, and the mass fraction of R is less than that of U;
[0058] As an embodiment of the application, the step of preparing the MOF material layer 3 on the electron transport layer 2 comprises:
[0059] Step A, dissolving the metal U salt solution and the metal R salt solution in the C solution, and after stirring uniformly, adding to the C solution containing the D solution to obtain a mixed solution, heating, cooling and filtering the mixed solution to obtain the MOF material doped with metal R atoms; the C solution is one or more of methanol, ethanol, isopropyl alcohol or acetone, and the D solution is one or more of dimethyl imidazole, N,N-dimethyl formamide and tris(2-benzimidazole methyl) amine;
[0060] Step B, mixing the MOF material doped with metal R atoms obtained in step A with the E solution to configure a precursor solution, and spin coating the precursor solution on the electron transport layer 2 and drying to form the MOF material layer 3; the E solution is one or more of DMF, DMSO, NMP and γ-butyrolactone.
[0061] Wherein, U and R are one or more of Zn, Ni, Fe, Co, Cu or rare earth metals, and U and R are different from each other, and the metal U salt solution and the metal R salt solution can be selected according to C8H 10 N4U 1-y Ry The metal U and the metal R in the C8H 10 N4U 1-y R y The metal U and the metal R in the C8H 10 N4Zn 1-y Ni y .
[0062] As a preferred embodiment of the present application, in step A, the metal U salt solution is zinc nitrate, zinc sulfate or zinc chloride, and the metal R salt solution is nickel acetylacetone, nickel nitrate, nickel sulfate or nickel chloride. In this embodiment, the C8H 10 N4U 1-y R y The metal U and the metal R in the C8H 10 N4Zn 1-y Ni y .
[0063] In this step A, the MOF material doped with metal R atoms can be prepared by one-step reaction, and the preparation method is simple. Moreover, compared with the traditional MOF material, in the traditional MOF material, trace metal R atoms are doped, the doped metal atoms are used to regulate the conductivity and energy band of the MOF material, the absorption of visible light is promoted, the trace metal R atoms have excellent stability, the perovskite absorption layer 4 is more stable, and the performance of the perovskite solar cell is improved. Moreover, only a small amount of metal R atoms need to be doped to improve the stability and conductivity of the perovskite absorption layer 4, and the cost is low.
[0064] In this step A, the ratio of the metal U salt solution, the metal R salt solution, the C solution and the D solution can be set according to actual conditions.
[0065] In this step A, the metal U salt solution and the metal R salt solution are dissolved by heating, and the dimethylimidazole, N,N-dimethylformamide or tris(2-benzimidazole methyl) amine is coordinated with the metal atoms in the reaction process of the metal U salt solution and the metal R salt solution, and the metal U-organic framework material (MOF material) doped with metal atoms R is formed. The filtration function is to filter some undissolved impurities and retain the generated MOF material doped with metal atoms.
[0066] As an embodiment of the present application, in step A, after the MOF material doped with metal R atoms is obtained by filtration, the method further comprises:
[0067] The MOF material doped with metal R atoms is cleaned by a cleaning solution.
[0068] In this embodiment, the MOF material doped with metal R atoms is cleaned by a cleaning solution to clean the organic residues in the pores and on the surface of the MOF material, so that the obtained MOF material has higher purity.
[0069] As an embodiment of the present application, the cleaning solution is DMF, methanol, or a mixed solution of DMF and methanol. Preferably, the MOF material framework residues of dimethyl imidazole, N,N-dimethyl formamide or tris(2-benzimidazole methyl) amine are first cleaned by DMF, and then the DMF is removed by methanol. In addition, the cleaning solution can also be pure water.
[0070] As an embodiment of the present application, the mass fraction of U in the MOF material layer 3 is 15-40%, and the mass fraction of R in the MOF material layer 3 is 0.5-10%. Since the mass fraction of R is 0.5-10% and the mass fraction of U is 15-40%, only a small amount of metal R atoms are doped in the MOF material of the MOF material layer 3 to control the conductivity and energy band of the MOF material layer 3, promote the absorption of visible light, and ensure that the cost is low.
[0071] As an embodiment of the present application, in step A, the molar ratio of metal U in the metal U salt solution to metal R in the metal R salt solution is 9-95, which ensures that the metal U and metal R in the generated MOF material meet the optimal proportion range, and improves the stability and conductivity of the MOF material layer 3.
[0072] As an embodiment of the present application, in step A, the metal U salt solution and the metal R salt solution are stirred uniformly and the C solution is stirred uniformly by ultrasonic stirring for 20-60 min.
[0073] As an embodiment of the present application, in step A, the heating temperature of the mixed solution is 100-150°C.
[0074] As a preferred embodiment of the present application, the mixed solution is heated by hydrothermal heating in an autoclave for 2-8h, that is, the obtained mixed solution is transferred to the autoclave to heat the mixed solution at 100°C, so that the mixed solution is heated more uniformly, which is beneficial to the reaction of the mixed solution to form the MOF material composed of MOF framework structures with a size of 100-500um, and avoids damage to the MOF material.
[0075] As an embodiment of the present application, the thickness of the MOF material layer 3 is 0.3-5um, which can ensure good conductivity of the MOF material layer 3 and absorption efficiency of the perovskite solar cell to sunlight.
[0076] Step S3, preparing a perovskite absorption layer 4 on the MOF material layer 3;
[0077] If the perovskite absorption layer 4 is made of pure organic perovskite or inorganic perovskite, the perovskite absorption layer 4 is prepared on the MOF material layer 3 by using the conventional preparation process of perovskite solar cells.
[0078] As a preferred embodiment of the present application, the perovskite absorption layer 4 is prepared by reacting perovskite crystals and MOF material doped with metal R atoms, the structure formula of the perovskite crystals is PbMAX3, X is one or more of F, Cl, Br, and I; the structure formula of the MOF material doped with metal R atoms is C8H 10 N4U 1-y R y ; U and R are one or more of Zn, Ni, Fe, Co, Cu, or rare earth metals, and U and R are different from each other, and the mass fraction of R is less than the mass fraction of U.
[0079] In this embodiment, the MOF material doped with metal R atoms of the perovskite absorption layer 4 has the same structure as the MOF material doped with metal R atoms of the MOF material layer 3, and the preparation process of the MOF material doped with metal R atoms of the perovskite absorption layer 4 is similar to the preparation process of the MOF material layer 3. The preparation method of the perovskite absorption layer 4 includes the following steps:
[0080] Step a, dissolving the metal U salt solution and the metal R salt solution in the C solution, stirring uniformly, and then adding to the C solution containing the D solution to obtain a mixed solution, heating, cooling, and filtering the mixed solution to obtain the MOF material doped with metal R atoms; the C solution is one or more of methanol, ethanol, isopropyl alcohol, or acetone, and the D solution is one or more of dimethylimidazole, N,N-dimethylformamide, and tris(2-benzimidazole methyl)amine;
[0081] In step a, U and R are one or more of Zn, Ni, Fe, Co, Cu, or rare earth metals, and U and R are different from each other. The metal U salt solution and the metal R salt solution can be selected according to the metal U and the metal R in C8H 10 N4U 1-y R y , and the metal U salt solution and the metal R salt solution can be inorganic metal salts or organic metal salts of different metals. For example, the metal U and the metal R of C8H 10 N4U 1-y R y are zinc and nickel respectively, the MOF material doped with metal atoms is nickel, and the structure formula of the MOF material doped with metal atoms nickel is C8H 10 N4Zn 1-y Ni y .
[0082] As a preferred embodiment of the present application, in step a, the metal U salt solution is zinc nitrate, zinc sulfate or zinc chloride, and the metal R salt solution is nickel acetylacetone, nickel nitrate, nickel sulfate or nickel chloride. In this embodiment, the metal U and the metal R correspond to zinc and nickel respectively, and the doping metal atom is nickel. The structural formula of the MOF material doped with the metal atom nickel is C8H 10 N4U 1-y R y The metal U and the metal R correspond to zinc and nickel respectively, and the doping metal atom is nickel. The structural formula of the MOF material doped with the metal atom nickel is C8H 10 N4Zn 1-y Ni y .
[0083] In this step a, the perovskite absorption layer 4 is prepared by one-step reaction of perovskite crystals (PbMAX3) and the MOF material (C8H 10 N4U 1-y R y ) doped with the metal atom R. On the one hand, the perovskite crystals and the framework of the MOF material are uniformly combined. The framework of the MOF material can stabilize the structure of the perovskite crystals, and the MOF material can act as an electron donor to increase the conductivity of the entire perovskite absorption layer 4, which is conducive to the separation of photo-generated carriers and improves the efficiency of the perovskite solar cell. On the other hand, compared with the single metal U metal-organic framework structure of the traditional MOF material, by doping the metal atom R, the metal U and the metal R in the MOF material (C8H 10 N4U 1-y R y ) form a metal-organic framework structure with non-metals. In this way, a small amount of metal atom R is used to regulate the conductivity and energy band of the MOF material, promote the absorption of visible light, and the doped metal atom R has excellent stability, making the perovskite absorption layer 4 more stable and improving the performance of the perovskite solar cell.
[0084] In this step a, the ratio of the metal U salt solution, the metal R salt solution, the C solution and the D solution can be set according to actual conditions.
[0085] In this step a, heating is used to accelerate the dissolution of the metal U salt solution and the metal R salt solution in the C solution and to accelerate the coordination of dimethylimidazole, N,N-dimethylformamide or tris(2-benzimidazole methyl) amine with the metal atoms in the metal U salt solution and the metal R salt solution during the reaction process, and to form a metal U-organic framework material (MOF material) doped with the metal atom R. Filtration is used to filter some undissolved impurities and retain the generated MOF material doped with the metal atom R.
[0086] As an embodiment of the present application, after the MOF material doped with the metal atom R is obtained by filtration in step a, the method further includes:
[0087] The MOF material doped with metal R atoms is cleaned by a cleaning solution.
[0088] In this embodiment, the MOF material doped with metal R atoms is cleaned by a cleaning solution to clean the organic residues in the pores and on the surface of the MOF material, so that the obtained MOF material has higher purity.
[0089] In step a, the cleaning solution is DMF, methanol, or a mixed solution of DMF and methanol. Preferably, the MOF material framework residues of dimethyl imidazole, N,N-dimethyl formamide or tris(2-benzimidazole methyl)amine are first cleaned by DMF, and then DMF is removed by methanol. In addition, the cleaning solution can also be pure water.
[0090] In step b, equal molar ratio of PbX2 and MAX is added to E solution, and stirred to configure a PbMAX3 solution, X is one or more of F, Cl, Br, and I, and E solution is one or more of DMF (N,N-dimethyl formamide), DMSO (dimethyl sulfoxide), NMP (N-methyl pyrrolidone), and γ-butyrolactone.
[0091] In this step b, PbX2 can be one or more of PbI2, PbBr2, PbCl2, and PbF2, and MAX can be one or more of MAI, MABr, and MACl. In this step, equal molar ratio of PbX2 and MAX is added to E solution, and the solution is stirred for 10-30 min to configure a PbMAX solution with a mass fraction of 45%.
[0092] In the embodiments of the present application, the order of steps a and b is not limited, that is, the MOF material doped with metal atoms can be prepared first, and then the perovskite solution is prepared, or the perovskite solution can be prepared first, and then the MOF material doped with metal R atoms is prepared. In addition, the MOF material doped with metal R atoms and the perovskite solution can also be prepared simultaneously.
[0093] In step c, the MOF material doped with metal R atoms obtained in step a and the PbMAX3 solution obtained in step b are added to E solution to configure a precursor solution; the precursor solution is spin-coated on the MOF material layer 3, and an anti-solvent is added dropwise to the MOF material layer 3 during the spin-coating process to obtain a perovskite precursor film, and the perovskite precursor film is annealed to form a perovskite absorption layer 4 composed of perovskite crystals and the MOF material doped with metal R atoms.
[0094] In this step c, E solution is one or more of DMF (N,N-dimethyl formamide), DMSO (dimethyl sulfoxide), NMP (N-methyl pyrrolidone), and γ-butyrolactone.
[0095] In the step c, the MOF material doped with metal R atoms obtained in the step a can be first added into the E solution for dissolution, and then the E solution containing the dissolved MOF material doped with metal R atoms is mixed with the PbMAX3 solution obtained in the step b to form the precursor solution. Alternatively, the MOF material doped with metal R atoms obtained in the step a and the PbMAX3 solution obtained in the step b can be sequentially added into the E solution and mixed to form the precursor solution.
[0096] As an embodiment of the present application, the molar ratio of PbMAX3 to C8H 10 N4U 1-y R y in the precursor solution is 0.5-5, so that the molar ratio of PbMAX3 to C8H 10 N4U 1-y R y in the perovskite absorption layer 4 prepared thereby is kept in the range of 0.5-5.
[0097] In the step c, the specific method of spin-coating the precursor solution on the MOF material layer 3 is not limited. After the precursor solution is spin-coated on the MOF material layer 3, an anti-solvent is added dropwise to the MOF material layer 3 to reduce the solubility of the perovskite crystals, so that the perovskite crystals and the MOF material doped with metal R atoms are precipitated to form a perovskite precursor film, and then annealing is performed to form the perovskite absorption layer 4 composed of perovskite crystals and the MOF material doped with metal R atoms.
[0098] As an embodiment of the present application, in the step c, the annealing temperature is 90-150°C, and the annealing time is 5-30 min.
[0099] As an embodiment of the present application, in the step c, the anti-solvent is chlorobenzene, ethyl acetate or a mixture of ethyl acetate and petroleum ether.
[0100] In step S4, a hole transport layer 5 is prepared on the perovskite absorption layer 4.
[0101] In the step, the hole transport layer 5 is prepared on the perovskite absorption layer 4, and the specific method is not limited, and the preparation process of the hole transport layer 5 of a conventional perovskite solar cell can be used.
[0102] In step S5, an electrode 6 is prepared on the hole transport layer 5.
[0103] As an embodiment of the present application, the step of preparing the electrode 6 on the hole transport layer 5 specifically includes: depositing a layer of electrode 6 on the hole transport layer 5 by using a thermal evaporation method.
[0104] The method for preparing the perovskite solar cell provided by the embodiment of the present application prepares a MOF material layer between the electron transport layer and the perovskite absorption layer, and the MOF material layer is composed of MOF material doped with metal R atoms; on the one hand, the MOF material has a porous and inter-granular gap structure, so that the MOF material layer has a larger contact area with the perovskite absorption layer and the electron transport layer, which is conducive to improving the conductivity between the electron transport layer and the perovskite absorption layer; on the other hand, a small amount of metal R atoms is doped in the metal-organic framework structure of the MOF material, and the doped metal R atoms are used to regulate the conductivity and energy band of the MOF material, which is conducive to matching the conduction band energy level of the MOF material with that of the perovskite, and is conducive to electron movement to improve the conductivity, thereby greatly improving the cell efficiency of the perovskite solar cell.
[0105] The above merely describes the preferred embodiments of the present application, but should not be used to limit the present application, and any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application.
Claims
1. A perovskite solar cell, comprising, from bottom to top, a transparent conductive layer, an electron transport layer, a perovskite absorber layer, a hole transport layer, and electrodes, characterized in that, The perovskite solar cell also includes: A MOF material layer is disposed between the electron transport layer and the perovskite absorber layer. The MOF material layer is composed of MOF material doped with metal R atoms, and the doped metal R atoms are chemically bonded to the non-metals of the MOF material. The structural formula of the MOF material is C8H. 10 N4U 1-y R y U and R are one or more of Zn, Ni, Fe, Co, Cu or rare earth metals, and U and R are different from each other, wherein the mass fraction of R is less than the mass fraction of U.
2. The perovskite solar cell according to claim 1, characterized in that, The mass fraction of U is 15-40%, and the mass fraction of R is 0.5-10%.
3. A perovskite solar cell according to claim 1, characterized in that, The doped metal R atoms are uniformly distributed within the framework of the MOF material.
4. A perovskite solar cell according to claim 1, characterized in that, The MOF material has a dodecahedral structure, and the doped metal R atoms are distributed at each vertex of the dodecahedral structure.
5. A perovskite solar cell according to claim 1, characterized in that, The thickness of the MOF material layer is 0.3~5 μm.
6. A method for fabricating a perovskite solar cell, characterized in that, Includes the following steps: An electron transport layer is fabricated on a transparent conductive layer; A MOF material layer is fabricated on the electron transport layer; the MOF material layer is composed of MOF material doped with metal R atoms, wherein the doped metal R atoms form chemical bonds with the nonmetals of the MOF material, and the structural formula of the MOF material is C8H. 10 N4U 1- y R y U and R are one or more of Zn, Ni, Fe, Co, Cu or rare earth metals, and U and R are different from each other, wherein the mass fraction of R is less than the mass fraction of U; A perovskite absorber layer is prepared on the MOF material layer; A hole transport layer is prepared on the perovskite absorber layer; Electrodes are fabricated on the hole transport layer.
7. The method for preparing a perovskite solar cell according to claim 6, characterized in that, The mass fraction of U is 15-40%, and the mass fraction of R is 0.5-10%.
8. The method for preparing a perovskite solar cell according to claim 6, characterized in that, The steps for fabricating a MOF material layer on the electron transport layer include: Step A: Dissolve the metal U salt solution and the metal R salt solution in solution C, stir until homogeneous, and then add the mixture to solution C containing solution D to obtain a mixed solution. Heat, cool, and filter the mixed solution to obtain the MOF material doped with metal R atoms. Solution C is one or more of methanol, ethanol, isopropanol, or acetone, and solution D is one or more of dimethylimidazole, N,N-dimethylformamide, and tris(2-benzimidazolemethyl)amine. Step B involves mixing the MOF material doped with metal R atoms obtained in Step A with the E solution to prepare a precursor solution, spin-coating the precursor solution onto the electron transport layer and drying it to form the MOF material layer; the E solution is one or more of DMF, DMSO, NMP, and γ-butyrolactone.
9. The method for preparing a perovskite solar cell according to claim 8, characterized in that, The metal U salt solution is one or more of zinc nitrate, zinc sulfate, or zinc chloride, and the metal R salt solution is one or more of nickel acetylacetone, nickel nitrate, nickel sulfate, or nickel chloride.
10. The method for preparing a perovskite solar cell according to claim 8, characterized in that, The molar ratio of metal U in the metal U salt solution to the molar ratio of metal R in the metal R salt solution is 9 to 95.
11. The method for preparing a perovskite solar cell according to claim 8, characterized in that, After obtaining the MOF material doped with metal R atoms through filtration, the process further includes: The MOF material doped with metal R atoms is cleaned using a cleaning solution.