Perovskite / crystalline silicon laminated solar cell and preparation method thereof
By introducing a metal oxide interface functional layer and a pyramid-shaped textured surface structure into perovskite/crystalline silicon tandem solar cells, the problems of low stability and low carrier transport efficiency of perovskite/crystalline silicon tandem solar cells are solved, achieving higher photoelectric conversion efficiency and stability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-31
- Publication Date
- 2026-04-07
AI Technical Summary
Existing perovskite/crystalline silicon tandem solar cells suffer from poor passivation layer stability and low carrier transport efficiency, failing to effectively address the ion migration problem in the perovskite active layer and thus limiting the improvement of cell performance.
An interface functional layer is introduced into the perovskite/crystalline silicon tandem solar cell. The material is a metal oxide, which is combined with the pyramid-shaped textured structure of the crystalline silicon base cell. Specific types of metal oxides such as Al, Si, Zr, Y and La oxides are used. The fabrication process includes spraying and drying to ensure that each layer is conformally aligned with the crystalline silicon base cell.
It improves interface stability, suppresses ion migration in the perovskite active layer, reduces interfacial carrier recombination and series resistance, enhances carrier transport efficiency and photoelectric conversion efficiency, and reduces production costs.
Smart Images
Figure CN121815889A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of perovskite solar cell technology, and more specifically, to a perovskite / crystalline silicon tandem solar cell and its fabrication method. Background Technology
[0002] Perovskite / crystalline silicon tandem solar cells combine the technological advantages of traditional monocrystalline silicon solar cells and novel perovskite solar cells, achieving a wider spectral absorption range and higher photoelectric conversion efficiency, making them a promising next-generation photovoltaic device. In perovskite / crystalline silicon tandem solar cells, the interface between the perovskite thin film and the electron transport layer contains numerous surface defects. These defects act as carrier recombination centers, leading to nonradiative recombination losses and significantly reducing the efficiency and stability of the photovoltaic device. To address this issue, a passivation layer is typically deposited to reduce interfacial recombination. However, traditional organic passivation layers have poor stability; inorganic passivation layers have limited passivation effects when thin, and thicker passivation layers increase interfacial series resistance, affecting carrier transport efficiency. To improve carrier transport efficiency, ultra-thin passivation layers (with thickness precisely controlled within a few or even one nanometer range) need to be fabricated. This not only places extremely high demands on processes and equipment but also hinders the large-area, low-cost production of perovskite / crystalline silicon tandem solar cells.
[0003] Furthermore, perovskite materials are prone to ion migration under light and environmental influences, leading to rapid performance degradation in photovoltaic devices. Existing passivation layers, due to limitations in their coverage methods, cannot effectively address the ion migration problem, thus limiting the long-term stability and lifespan of perovskite / crystalline silicon tandem solar cells.
[0004] It is evident that existing passivation layers struggle to balance stability and high carrier transport efficiency, and cannot effectively address the ion migration problem in the perovskite active layer, thus limiting the performance improvement of perovskite / crystalline silicon tandem solar cells.
[0005] In summary, the research and development of a perovskite / crystalline silicon tandem solar cell and its fabrication method are of great significance for solving the ion migration phenomenon in the perovskite active layer and improving the interfacial stability of perovskite / crystalline silicon tandem solar cells. Summary of the Invention
[0006] The main objective of this application is to provide a perovskite / crystalline silicon tandem solar cell and its fabrication method, in order to solve the problems of poor stability and low carrier transport efficiency of the passivation layer in the existing perovskite / crystalline silicon tandem solar cell, as well as the inability to effectively solve the problem of ion migration in the perovskite active layer.
[0007] To achieve the above objectives, this application provides a perovskite / crystalline silicon tandem solar cell, comprising a crystalline silicon base cell, a tunneling layer, a first carrier transport layer, a perovskite active layer, an interface functional layer, a second carrier transport layer, and a metal electrode layer stacked sequentially; wherein, the interface functional layer is made of a metal oxide, and the metal element in the metal oxide is selected from one or more elements in Group IIIA, Group IIIB, Group IVA, and Group IVB; the crystalline silicon base cell has a pyramidal textured structure; the tunneling layer, the first carrier transport layer, the perovskite active layer, the interface functional layer, and the second carrier transport layer are all conformally aligned with the crystalline silicon base cell.
[0008] Further, the metal element is selected from one or more of the group consisting of Al, Si, Zr, Y and La; preferably, the metal oxide is selected from one or more of the group consisting of aluminum oxide, silicon dioxide, zirconium dioxide, yttrium oxide and lanthanum oxide; preferably, the thickness of the interface functional layer is 20 to 200 nm, more preferably 30 to 50 nm.
[0009] Further, the average height of the pyramid-shaped textured structure of the perovskite active layer is 1.5–2.5 μm; the thickness of the perovskite active layer is 750–1250 nm, preferably 750–900 nm; preferably, the coverage of the interface functional layer on the surface of the perovskite active layer is 85–98%; preferably, the band gap of the perovskite active layer is 1.55–1.75 eV, preferably 1.65–1.68 eV; preferably, the material of the perovskite active layer is ABX3; wherein, A is selected from CH3NH3. + NH=CHNH3 + and Cs + One or more of the groups, where B is selected from Pb 2+ and / or Sn 2+ X is selected from Cl - ,Br - and I - One or more of the groups.
[0010] Further, the first carrier transport layer is a hole transport layer, and the second carrier transport layer is an electron transport layer; preferably, the thickness of the hole transport layer is 2–20 nm, more preferably 2–5 nm; preferably, the hole transport layer is a self-assembled monolayer; the material of the hole transport layer is selected from poly-[4-(9H-carbazole-9-yl)butyl]phosphonic acid, [4-(9H-carbazole-9-yl)butyl]phosphonic acid, (4-(7H-dibenzo[c,g]carbazole-7-yl) One or more of the following groups: (phenyl)phosphonic acid, (2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl)phosphonic acid, (4-(3,11-dimethoxy-7H-dibenzo[c,g]carbazole-7-yl)butyl)phosphonic acid, and (4-(3,6-dibromo-9H-carbazole-9-yl)butyl)phosphonic acid; preferably, the thickness of the electron transport layer is 15-35 nm; preferably, the material of the electron transport layer is solvent-based tin oxide nanoparticles.
[0011] Furthermore, the crystalline silicon bottom cell is selected from HJT cells, BC cells, or TOPCon cells.
[0012] Furthermore, the thickness of the tunneling layer is 5–20 nm; preferably, the material of the tunneling layer is selected from indium tin oxide and / or indium zinc oxide.
[0013] Furthermore, the thickness of the metal electrode layer is 5–30 μm; preferably, the material of the metal electrode layer is selected from one or more of the group consisting of Ag, Cu and Al.
[0014] Furthermore, a transparent conductive oxide layer is disposed between the second carrier transport layer and the metal electrode layer; the transparent conductive oxide layer is conformally aligned with the crystalline silicon bottom cell; preferably, the thickness of the transparent conductive oxide layer is 15-30 nm; preferably, the material of the transparent conductive oxide layer is selected from indium zinc oxide and / or indium tin oxide.
[0015] Furthermore, an antireflection layer is provided on the side of the metal electrode layer away from the crystalline silicon base cell; the antireflection layer is conformal to the crystalline silicon base cell; preferably, the thickness of the antireflection layer is 100-200 nm; preferably, the material of the antireflection layer is selected from magnesium fluoride and / or silicon dioxide.
[0016] To achieve the above objectives, another aspect of this application provides a method for fabricating the perovskite / crystalline silicon tandem solar cell provided in this application. The method includes: step S1, preparing a crystalline silicon base cell; the crystalline silicon base cell has a pyramidal textured surface structure; step S2, fabricating a tunneling layer on one side of the conductive surface of the crystalline silicon base cell; step S3, fabricating a first carrier transport layer on the surface of the tunneling layer away from the crystalline silicon base cell; step S4, fabricating a perovskite active layer on the surface of the first carrier transport layer away from the crystalline silicon base cell; and step S5, spraying a first mixture containing metal oxides onto the perovskite active layer. The surface of the active layer away from the crystalline silicon base cell is dried first to obtain an interface functional layer; the metal element in the metal oxide is selected from one or more elements in Group IIIA, Group IIIB, Group IVA and Group IVB; in step S6, a second carrier transport layer is prepared on the surface of the interface functional layer away from the crystalline silicon base cell; in step S7, a metal electrode layer is prepared on the surface of the second carrier transport layer to obtain a perovskite / crystalline silicon tandem solar cell; wherein, the tunneling layer, the first carrier transport layer, the perovskite active layer, the interface functional layer and the second carrier transport layer are all conformally consistent with the crystalline silicon base cell.
[0017] Further, step S5 also includes mixing the metal oxide with a first organic solvent to obtain a first mixture; preferably, the mass concentration of the metal oxide in the first mixture is 0.01-5 wt%; preferably, the average particle size of the metal oxide is 5-30 nm; preferably, the metal element in the metal oxide is selected from one or more of the group consisting of Al, Si, Zr, Y and La; more preferably, the metal oxide is selected from one or more of the group consisting of aluminum oxide, silicon dioxide, zirconium dioxide, yttrium oxide and lanthanum oxide; preferably, the first organic solvent is selected from alcohol solvents and / or acid solvents; more preferably, the first organic solvent is selected from one or more of the group consisting of acetic acid, propionic acid, ethanol, isopropanol, n-butanol or isooctanol.
[0018] Furthermore, during the spraying process, the distance between the nozzle and the perovskite active layer is 5-10 cm, the pressure is 1-5 kPa, the flow rate is 0.2-1 mL / min, and the moving speed is 80-120 mm / s; preferably, in step S5, ultrasonic spraying is used for spraying, with an ultrasonic frequency of 50-120 kHz and a power of 1-15 W.
[0019] Furthermore, a first heating device is used for the first drying, with a temperature of 100–120°C and a time of 5–15 min; or, a vacuum crystallizer or air knife is used for the first drying, with a temperature of 18–25°C and a time of 30–120 s.
[0020] Further, the second carrier transport layer is an electron transport layer. Step S6 includes: mixing solvent-based tin oxide nanoparticles with a second organic solvent to obtain a second mixture; spraying the second mixture onto the surface of the interface functional layer away from the crystalline silicon bottom cell, and obtaining the electron transport layer after a second drying; preferably, the mass concentration of solvent-based tin oxide nanoparticles in the second mixture is 0.5-2 wt%; preferably, the average particle size of the solvent-based tin oxide nanoparticles is 5-20 nm; preferably, the second organic solvent is selected from acid solvents and / or alcohol solvents; preferably, the second organic solvent is selected from one or more of the group consisting of acetic acid, isopropanol, n-butanol, and isooctanol; preferably, in step S6, the spraying is performed by ultrasonic spraying or inkjet printing; preferably, the second drying is performed by a second heating device at a temperature of 100-120°C for a time of 5-15 min; or, the second drying is performed by a vacuum crystallizer or an air knife at a temperature of 18-25°C for a time of 30-120 s.
[0021] Furthermore, between steps S6 and S7, a transparent conductive oxide layer is prepared on the surface of the second carrier transport layer away from the crystalline silicon base cell; the transparent conductive oxide layer is conformally oriented to the crystalline silicon base cell.
[0022] Furthermore, step S7 also includes: preparing an antireflection layer on the surface of the metal electrode layer away from the crystalline silicon base cell; the antireflection layer is conformally aligned with the crystalline silicon base cell.
[0023] Compared to traditional perovskite / crystalline silicon tandem solar cells, the technical solution of this application includes an interface functional layer between the perovskite active layer and the second carrier transport layer. This interface functional layer is made of a metal oxide, which effectively improves the chemical stability of the interface functional layer and, to a certain extent, suppresses ion migration in the perovskite active layer, thus enhancing interface stability. It also reduces interfacial carrier recombination caused by direct contact between the perovskite active layer and the second carrier transport layer, thereby reducing interfacial series resistance and improving carrier transport efficiency. Compared to other types, the use of this specific type of metal oxide effectively passivates surface defects between the perovskite active layer and the second carrier transport layer, reducing non-radiative recombination losses and lowering interfacial series resistance, thus improving carrier transport efficiency. The pyramidal textured structure of the crystalline silicon bottom cell improves the photoelectric conversion efficiency of the perovskite / crystalline silicon tandem solar cell. The conformal arrangement of the other layers with the crystalline silicon bottom cell improves the uniform contact between the materials of each layer, thereby improving carrier transport efficiency and ultimately enhancing the photoelectric conversion efficiency of the perovskite / crystalline silicon tandem solar cell. In summary, introducing the aforementioned specific types of interface functional layers into perovskite / crystalline silicon tandem solar cells can effectively improve the stability and photoelectric conversion efficiency of perovskite / crystalline silicon tandem solar cells, while also reducing production costs. Attached Figure Description
[0024] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings:
[0025] Figure 1 A schematic diagram of the stacked structure of a perovskite / crystalline silicon tandem solar cell according to a preferred embodiment of this application is shown.
[0026] Figure 2 A schematic diagram of the stacked structure of a perovskite / crystalline silicon tandem solar cell according to another preferred embodiment of this application is shown.
[0027] The above figures include the following reference numerals:
[0028] 100. Crystalline silicon bottom cell; 200. Tunneling layer; 300. First carrier transport layer; 400. Perovskite active layer; 500. Interface functional layer; 600. Second carrier transport layer; 700. Metal electrode layer; 800. Transparent conductive oxide layer; 900. Anti-reflection layer. Detailed Implementation
[0029] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present application will now be described in detail with reference to the embodiments.
[0030] As described in the background section, existing perovskite / crystalline silicon tandem solar cells suffer from poor passivation layer stability, low carrier transport efficiency, and an inability to effectively address the ion migration problem in the perovskite active layer. To solve these technical problems, this application provides a perovskite / crystalline silicon tandem solar cell, such as... Figure 1 As shown, the perovskite / crystalline silicon tandem solar cell includes a crystalline silicon base cell 100, a tunneling layer 200, a first carrier transport layer 300, a perovskite active layer 400, an interface functional layer 500, a second carrier transport layer 600, and a metal electrode layer 700, which are stacked sequentially. The interface functional layer 500 is made of metal oxide, and the metal element in the metal oxide is selected from one or more elements in Group IIIA, Group IIIB, Group IVA, and Group IVB. The crystalline silicon base cell 100 has a pyramid-shaped textured structure. The tunneling layer 200, the first carrier transport layer 300, the perovskite active layer 400, the interface functional layer 500, and the second carrier transport layer 600 are all conformally aligned with the crystalline silicon base cell 100.
[0031] Compared to traditional perovskite / crystalline silicon tandem solar cells, this application further includes an interface functional layer 500 between the perovskite active layer 400 and the second carrier transport layer 600. The interface functional layer 500 is made of a metal oxide, which effectively improves the chemical stability of the interface functional layer 500 and, to a certain extent, suppresses ion migration in the perovskite active layer 400, thus enhancing interface stability. Simultaneously, it reduces interfacial carrier recombination caused by direct contact between the perovskite active layer 400 and the second carrier transport layer 600, thereby reducing interfacial series resistance and improving carrier transport efficiency. Compared to other types, the use of this specific type of metal oxide effectively passivates surface defects between the perovskite active layer 400 and the second carrier transport layer 600, reducing non-radiative recombination losses, while also lowering interfacial series resistance and improving carrier transport efficiency. The pyramidal textured structure of the crystalline silicon base cell 100 improves the photoelectric conversion efficiency of the perovskite / crystalline silicon tandem solar cell. The conformal arrangement of the other layers with the crystalline silicon base cell 100 enhances the uniform contact between the materials, thereby improving carrier transport efficiency and ultimately increasing the photoelectric conversion efficiency of the perovskite / crystalline silicon tandem solar cell. In summary, introducing the aforementioned specific type of interface functional layer 500 into the perovskite / crystalline silicon tandem solar cell effectively improves its stability and photoelectric conversion efficiency while also reducing production costs.
[0032] It should be noted that, in this application, perovskite / crystalline silicon tandem solar cells refer to tandem solar cells with a double-layer tandem structure, wherein the crystalline silicon bottom cell 100 and the perovskite top cell are connected in series.
[0033] In a preferred embodiment, the metal element includes, but is not limited to, one or more elements from the group consisting of Al, Si, Zr, Y, and La. Compared to other ranges, limiting the types of metal elements to the above range is beneficial for improving the chemical stability of the interfacial functional layer 500, for suppressing ion migration in the perovskite active layer 400, and for passivating surface defects between the perovskite active layer 400 and the second carrier transport layer 600, reducing non-radiative recombination losses, and lowering the interfacial series resistance, thereby improving the carrier transport efficiency.
[0034] In a preferred embodiment, the metal oxide includes, but is not limited to, one or more of the group consisting of aluminum oxide, silicon dioxide, zirconium dioxide, yttrium oxide, and lanthanum oxide. Compared to other types, the aforementioned metal oxides are widely available, have lower costs, and are beneficial for improving the chemical stability of the interface functional layer 500, suppressing ion migration in the perovskite active layer 400, and passivating surface defects between the perovskite active layer 400 and the second carrier transport layer 600, reducing non-radiative recombination losses, lowering the interface series resistance, and improving carrier transport efficiency.
[0035] In order to further improve the chemical and structural stability of the interface functional layer 500, further suppress ion migration in the perovskite active layer 400, and further passivate the surface defects between the perovskite active layer 400 and the second carrier transport layer 600, reduce the interface series resistance, and further improve the carrier transport efficiency, in a preferred embodiment, the thickness of the interface functional layer 500 is 20-200 nm.
[0036] To further improve the chemical and structural stability of the interface functional layer 500, further suppress ion migration in the perovskite active layer 400, reduce the interfacial series resistance, and further improve the carrier transport efficiency, the thickness of the interface functional layer 500 is preferably 30-50 nm.
[0037] In a preferred embodiment, the average height of the pyramidal textured structure of the perovskite active layer 400 is 1.5–2.5 μm, and the thickness of the perovskite active layer 400 is 750–1250 nm. The average height of the pyramidal textured structure and the thickness of the perovskite active layer 400 are not limited to the above ranges. Limiting them to these ranges is beneficial for improving the light absorption efficiency, carrier transport efficiency, and collection efficiency of the perovskite active layer 400. It also helps to improve the structural stability of the perovskite active layer 400, thereby improving the photoelectric conversion efficiency and stability of the perovskite / crystalline silicon tandem solar cell.
[0038] To further improve the light absorption efficiency and structural stability of the perovskite active layer 400, and to further improve the carrier transport efficiency and collection efficiency, the thickness of the perovskite active layer 400 is preferably 750–900 nm.
[0039] To further reduce carrier recombination, lower series resistance, and further improve carrier transport efficiency, in a preferred embodiment, the coverage of the interface functional layer 500 on the surface of the perovskite active layer 400 is 85-98%. It should be noted that the coverage of the interface functional layer 500 on the surface of the perovskite active layer 400 refers to the percentage of the area of the interface functional layer 500 material deposited on the surface of the perovskite active layer 400 relative to the total area of the perovskite active layer 400.
[0040] In a preferred embodiment, the band gap of the perovskite active layer 400 is 1.55–1.75 eV. The band gap of the perovskite active layer 400 includes, but is not limited to, the above range. Limiting it to this range is beneficial for improving the light absorption efficiency of the perovskite active layer 400, thereby improving the photoelectric conversion efficiency of the perovskite / crystalline silicon tandem solar cell.
[0041] To further improve the light absorption efficiency of the perovskite active layer 400, and thus further improve the photoelectric conversion efficiency of the perovskite / crystalline silicon tandem solar cell, preferably, the band gap of the perovskite active layer 400 is 1.65 to 1.68 eV.
[0042] In a preferred embodiment, the perovskite active layer 400 is made of ABX3; wherein, A includes, but is not limited to, CH3NH3. + NH=CHNH3 + and Cs + One or more of the groups, B including but not limited to Pb 2+ and / or Sn 2+ X includes, but is not limited to, Cl - ,Br - and I - One or more of the groups constituted. The materials of the perovskite active layer 400 include, but are not limited to, the range described above. Limiting them to the range described above is beneficial to improving the light absorption efficiency and stability of the perovskite active layer 400, thereby improving the photoelectric conversion efficiency and stability of the perovskite / crystalline silicon tandem solar cell.
[0043] The perovskite / crystalline silicon tandem solar cell provided in this application can be a pin-type perovskite / crystalline silicon tandem solar cell. In a preferred embodiment, the first carrier transport layer 300 is a hole transport layer, and the second carrier transport layer 600 is an electron transport layer.
[0044] In a preferred embodiment, the thickness of the hole transport layer is 2–20 nm. The thickness of the hole transport layer includes, but is not limited to, the above range. Limiting it to this range helps reduce carrier recombination and improve carrier transport efficiency, thereby improving the photoelectric conversion efficiency of the perovskite / crystalline silicon tandem solar cell.
[0045] To further reduce carrier recombination and improve carrier transport efficiency, the hole transport layer is preferably 2-5 nm thick.
[0046] Self-assembled monolayers (SAM layers) can tightly bond with perovskite layers to form highly stable and uniform interfacial contacts, which helps to reduce carrier recombination and improve carrier transport efficiency. In a preferred embodiment, the hole transport layer is a self-assembled monolayer.
[0047] To further improve the carrier transport efficiency of the hole transport layer, preferably, the material of the hole transport layer includes, but is not limited to, one or more of the following groups: poly-[4-(9H-carbazole-9-yl)butyl]phosphonic acid, [4-(9H-carbazole-9-yl)butyl]phosphonic acid, (4-(7H-dibenzo[c,g]carbazole-7-yl)phenyl)phosphonic acid, (2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl)phosphonic acid, (4-(3,11-dimethoxy-7H-dibenzo[c,g]carbazole-7-yl)butyl)phosphonic acid, and (4-(3,6-dibromo-9H-carbazole-9-yl)butyl)phosphonic acid.
[0048] In a preferred embodiment, the thickness of the electron transport layer is 15–35 nm. The thickness of the electron transport layer includes, but is not limited to, the above range. Limiting it to this range helps reduce carrier recombination and improves electron transport efficiency, thereby improving the photoelectric conversion efficiency of the perovskite / crystalline silicon tandem solar cell.
[0049] In a preferred embodiment, the electron transport layer is made of solvent-based tin oxide nanoparticles. These solvent-based tin oxide nanoparticles can be uniformly dispersed in an organic solvent, enabling solution-based fabrication of the electron transport layer. This also improves the stability of the electron transport layer in humid environments. Depositing the electron transport layer made of solvent-based tin oxide nanoparticles onto the surface of the perovskite active layer 400 can completely replace C. 60 The film layer plays a crucial role in significantly reducing production costs; simultaneously, compared to perovskite active layers 400 and C... 60 The perovskite active layer 400 and the tin oxide nanoparticle film have stronger interfacial bonding, which is beneficial to improving the mechanical stability of perovskite / crystalline silicon tandem solar cells.
[0050] It should be noted that the solvent-based tin oxide nanoparticles in this application may be Tinfab solvent-based tin oxide nanoparticles manufactured by Sofab Inks LLC, or solvent-based tin oxide nanoparticles with similar properties manufactured by other companies.
[0051] In a preferred embodiment, the crystalline silicon base cell 100 includes, but is not limited to, any one of HJT (heterojunction) cells, BC (back contact) cells, or TOPCon (tunneling oxide passivated contact) cells. Compared to other types, using the above-described type of crystalline silicon base cell 100 is beneficial for improving the stability and photoelectric conversion efficiency of perovskite / crystalline silicon tandem solar cells.
[0052] In a preferred embodiment, the thickness of the tunneling layer 200 is 5–20 nm. The thickness of the tunneling layer 200 includes, but is not limited to, the above range. Limiting it to the above range is beneficial for reducing carrier recombination, lowering interface resistance, and improving carrier transport efficiency, thereby improving the photoelectric conversion efficiency and stability of the fabricated perovskite / crystalline silicon tandem solar cell.
[0053] In order to further reduce carrier recombination, lower interface resistance, further improve carrier transport efficiency, and further improve the stability of the tunneling layer 200, thereby further improving the photoelectric conversion efficiency and stability of the fabricated perovskite / crystalline silicon tandem solar cell, in a preferred embodiment, the material of the tunneling layer 200 includes, but is not limited to, indium tin oxide (ITO) and / or indium zinc oxide (IZO).
[0054] In a preferred embodiment, the thickness of the metal electrode layer 700 is 5–30 μm. The thickness of the metal electrode layer 700 includes, but is not limited to, the above range. Limiting it to this range is beneficial for improving the conductivity and stability of the metal electrode layer 700, thereby improving the photoelectric conversion efficiency and stability of the perovskite / crystalline silicon tandem solar cell.
[0055] To further improve the conductivity and stability of the metal electrode layer 700, in a preferred embodiment, the material of the metal electrode layer 700 includes, but is not limited to, one or more of the group consisting of Ag, Cu and Al.
[0056] like Figure 2As shown, in a preferred embodiment, a transparent conductive oxide layer 800 is further disposed between the second carrier transport layer 600 and the metal electrode layer 700; the transparent conductive oxide layer 800 is conformally fitted to the crystalline silicon bottom cell 100. The provision of the transparent conductive oxide layer 800 is beneficial to improving carrier transport efficiency, enhancing its passivation effect on interface defects, and protecting the perovskite active layer 400, thereby improving the photoelectric conversion efficiency and stability of the perovskite / crystalline silicon tandem solar cell.
[0057] In order to further improve electron transport efficiency, thereby further improving the photoelectric conversion efficiency and stability of perovskite / crystalline silicon tandem solar cells, in a preferred embodiment, the thickness of the transparent conductive oxide layer 800 is 15-30 nm.
[0058] In a preferred embodiment, the material of the transparent conductive oxide layer 800 includes, but is not limited to, indium zinc oxide (IZO) and / or indium tin oxide (ITO). Compared to other types, using the above-mentioned materials as the material of the transparent conductive oxide layer 800 is beneficial to improving electron transport efficiency, thereby improving the photoelectric conversion efficiency and stability of perovskite / crystalline silicon tandem solar cells.
[0059] like Figure 2 As shown, in a preferred embodiment, an antireflection layer 900 is further disposed on the surface of the metal electrode layer 700 away from the crystalline silicon base cell 100; the antireflection layer 900 is conformally fitted to the crystalline silicon base cell 100. The provision of the antireflection layer 900 helps to reduce light reflection loss, thereby helping to improve the photoelectric conversion efficiency of the perovskite / crystalline silicon tandem solar cell.
[0060] In order to further reduce light reflection loss and thus further improve the photoelectric conversion efficiency of perovskite / crystalline silicon tandem solar cells, in a preferred embodiment, the antireflection layer 900 is made of materials including but not limited to magnesium fluoride and / or silicon dioxide.
[0061] In a preferred embodiment, the thickness of the antireflection layer 900 is 100–200 nm. The thickness of the antireflection layer 900 includes, but is not limited to, the above range. Limiting it to this range helps reduce light reflection loss and improves the photoelectric conversion efficiency and stability of the perovskite / crystalline silicon tandem solar cell.
[0062] The second aspect of this application also provides a method for fabricating the perovskite / crystalline silicon tandem solar cell described above. The method includes: step S1, preparing a crystalline silicon base cell 100 for later use; the crystalline silicon base cell 100 has a pyramidal textured surface structure; step S2, fabricating a tunneling layer 200 on one side of the conductive surface of the crystalline silicon base cell 100; step S3, fabricating a first carrier transport layer 300 on the surface of the tunneling layer 200 away from the crystalline silicon base cell 100; step S4, fabricating a perovskite active layer 400 on the surface of the first carrier transport layer 300 away from the crystalline silicon base cell 100; and step S5, spraying a first mixture containing metal oxides onto the perovskite active layer 400 away from the crystalline silicon base cell 100. After a first drying process, an interface functional layer 500 is obtained on one side surface of cell 100; the metal element in the metal oxide is selected from one or more elements in the group consisting of elements in Group IIIA, Group IIIB, Group IVA and Group IVB; in step S6, a second carrier transport layer 600 is prepared on the side surface of the interface functional layer 500 away from the crystalline silicon bottom cell 100; in step S7, a metal electrode layer 700 is prepared on the side surface of the second carrier transport layer 600 to obtain a perovskite / crystalline silicon tandem solar cell; wherein, the tunneling layer 200, the first carrier transport layer 300, the perovskite active layer 400, the interface functional layer 500 and the second carrier transport layer 600 are all conformally consistent with the crystalline silicon bottom cell 100.
[0063] The above preparation method can yield a product with the following properties: Figure 1 The perovskite / crystalline silicon tandem solar cell with the shown tandem structure. In step S1, a crystalline silicon bottom cell 100 with a pyramidal textured surface is prepared for use, which can improve the photoelectric conversion efficiency of the fabricated perovskite / crystalline silicon tandem solar cell. Through steps S2, S3, and S4, a tunneling layer 200, a first carrier transport layer 300, and a perovskite active layer 400 that are conformally consistent with the crystalline silicon bottom cell 100 are obtained. In step S5, a first mixture containing metal oxides is sprayed onto the surface of the perovskite active layer 400 to prepare a conformal interface functional layer 500, which can effectively improve the chemical stability of the fabricated interface functional layer 500, suppress ion migration in the perovskite active layer 400 to a certain extent, improve interface stability, and at the same time reduce the interface carrier recombination caused by direct contact between the perovskite active layer 400 and the second carrier transport layer 600, thereby reducing the interface series resistance and improving the carrier transport efficiency. Step S6 yields a second carrier transport layer 600 conformally to the crystalline silicon base cell 100. Step S7 fabricates a metal electrode layer 700, resulting in a perovskite / crystalline silicon tandem solar cell with superior overall performance. The perovskite / crystalline silicon tandem solar cell fabricated using the above-described method of this application exhibits higher photoelectric conversion efficiency and better stability.
[0064] In order to improve the dispersibility of the metal oxide and thus facilitate the preparation of the interface functional layer 500 by solution method, in a preferred embodiment, step S5 further includes mixing the metal oxide with a first organic solvent to obtain a first mixture.
[0065] In a preferred embodiment, the mass concentration of the metal oxide in the first mixture is 0.01–5 wt%. The mass concentration of the metal oxide includes, but is not limited to, the above range. Limiting it to this range is beneficial for improving the dispersion uniformity of the metal oxide, which in turn improves the interfacial interaction between the interfacial functional layer 500 and the perovskite active layer 400, resulting in a more uniform and appropriately thick interfacial functional layer 500. This, in turn, helps to suppress ion migration in the perovskite active layer 400, reduce carrier recombination, lower the interfacial series resistance, and improve carrier transport efficiency.
[0066] In order to obtain an interface functional layer 500 with better film quality, thereby further reducing carrier recombination and further improving carrier transport efficiency, in a preferred embodiment, the average particle size of the metal oxide is 5-30 nm.
[0067] In a preferred embodiment, the metal element in the metal oxide includes, but is not limited to, one or more elements from the group consisting of Al, Si, Zr, Y, and La. Compared to other ranges, limiting the types of metal elements to the above range is beneficial for improving the chemical stability of the interfacial functional layer 500, for suppressing ion migration in the perovskite active layer 400, and for passivating surface defects between the perovskite active layer 400 and the second carrier transport layer 600, reducing nonradiative recombination losses, and lowering the interfacial series resistance, thereby improving carrier transport efficiency.
[0068] In a preferred embodiment, the metal oxide includes, but is not limited to, one or more of the group consisting of aluminum oxide, silicon dioxide, zirconium dioxide, yttrium oxide, and lanthanum oxide. Compared to other types, the aforementioned metal oxides are widely available, have lower costs, and are beneficial for improving the chemical stability of the interface functional layer 500, suppressing ion migration in the perovskite active layer 400, and passivating surface defects between the perovskite active layer 400 and the second carrier transport layer 600, reducing non-radiative recombination losses, lowering the interface series resistance, and improving carrier transport efficiency.
[0069] To further improve the dispersibility of the metal oxide and facilitate obtaining a more uniformly dispersed first mixture, in a preferred embodiment, the first organic solvent includes, but is not limited to, alcohol solvents and / or acid solvents; preferably, the first organic solvent includes, but is not limited to, one or more of the group consisting of acetic acid, propionic acid, ethanol, isopropanol, n-butanol or isooctanol.
[0070] In a preferred embodiment, the distance between the spray nozzle and the perovskite active layer 400 during the spraying process is 5–10 cm, the pressure is 1–5 kPa, the flow rate is 0.2–1 mL / min, and the moving speed is 80–1200 mm / s. Compared to other ranges, limiting the above process parameters within these ranges is beneficial for improving spraying efficiency and for improving the interfacial interaction between the interface functional layer 500 and the perovskite active layer 400, resulting in a more uniform thickness of the interface functional layer 500 and improving its film quality. This, in turn, helps to improve the photoelectric conversion efficiency and stability of the perovskite / crystalline silicon tandem solar cell.
[0071] It should be noted that the nozzle movement rate in this application refers to the rate at which the nozzle moves in a direction parallel to the surface of the perovskite active layer 400.
[0072] Ultrasonic spraying can produce fine and uniform droplets, making it suitable for forming coatings on irregular or three-dimensional surfaces. In a preferred embodiment, in step S5, ultrasonic spraying is performed with an ultrasonic frequency of 50–120 kHz and a power of 1–15 W. Compared to other methods and ranges, using ultrasonic spraying and limiting its ultrasonic frequency and power within the above range is beneficial for improving spraying efficiency and for preparing a conformal interface functional layer 500 on the surface of the perovskite active layer 400 with a pyramidal textured surface, thereby improving the film quality of the interface functional layer 500.
[0073] In order to remove the residual first organic solvent in the interface functional layer 500, improve the removal efficiency of the first organic solvent, obtain an interface functional layer 500 that conforms to the perovskite active layer 400, and further improve its film quality, in a preferred embodiment, a first heating device is used for first drying, the temperature of the first drying is 100-120°C, and the time is 5-15 min; or, a vacuum crystallizer or air knife is used for first drying, the temperature of the first drying is 18-25°C, and the time is 30-120 s.
[0074] The perovskite / crystalline silicon tandem solar cell provided in this application can be a pin-type perovskite / crystalline silicon tandem solar cell. In a preferred embodiment, the second carrier transport layer 600 is an electron transport layer.
[0075] In a preferred embodiment, step S6 includes: mixing solvent-based tin oxide nanoparticles with a second organic solvent to obtain a second mixture; spraying the second mixture onto the surface of the interfacial functional layer 500 away from the crystalline silicon bottom cell 100, and obtaining an electron transport layer after a second drying. Compared with other methods, the above method is advantageous for preparing an electron transport layer that is conformally aligned with the surface of the interfacial functional layer 500, which helps reduce interfacial defects, improves carrier transport efficiency, and also helps improve the film quality and stability of the electron transport layer.
[0076] In a preferred embodiment, the mass concentration of solvent-based tin oxide nanoparticles in the second mixture is 0.5–2 wt%. The mass concentration of solvent-based tin oxide nanoparticles includes, but is not limited to, the above range. Limiting it to the above range is beneficial to improving the dispersion uniformity of solvent-based tin oxide nanoparticles, and to obtaining a uniform electron transport layer with a more suitable thickness. This is beneficial to reducing carrier recombination, lowering interfacial series resistance, and improving carrier transport efficiency.
[0077] In order to improve the dispersibility of solvent-based tin oxide nanoparticles and obtain an electron transport layer with better film quality, thereby further reducing carrier recombination and improving carrier transport efficiency, in a preferred embodiment, the average particle size of the solvent-based tin oxide nanoparticles is 5-20 nm.
[0078] To further improve the dispersibility of solvent-based tin oxide nanoparticles and facilitate obtaining a more uniformly dispersed second mixture, in a preferred embodiment, the second organic solvent includes, but is not limited to, acid solvents and / or alcohol solvents; preferably, the second organic solvent includes, but is not limited to, one or more of the group consisting of acetic acid, isopropanol, n-butanol and isooctyl alcohol.
[0079] In a preferred embodiment, step S6 involves spraying using ultrasonic spraying or inkjet printing. Compared to other methods, these methods can produce fine and uniform droplets, making them more suitable for forming coatings on irregular or three-dimensional surfaces. This facilitates obtaining an electron transport layer that conforms to the interface functional layer 500, thereby improving the film quality of the electron transport layer.
[0080] In order to remove the residual second organic solvent in the electron transport layer, improve the removal efficiency of the second organic solvent, obtain an electron transport layer that conforms to the interface functional layer 500, and further improve its film quality, in a preferred embodiment, a second heating device is used for second drying, the temperature of the second drying is 100-120°C, and the time is 5-15 min; or, a vacuum crystallizer or air knife is used for second drying, the temperature of the second drying is 18-25°C, and the time is 30-120 s.
[0081] To remove the second organic solvent more quickly and further improve the film quality of the electron transport layer, a vacuum crystallizer or air knife is preferably used for the second drying.
[0082] To improve carrier collection efficiency and stability, the metal electrode layer 700 in this application is configured with a smooth and flat structure. In a preferred embodiment, the metal electrode layer 700 is fabricated using screen printing.
[0083] To further improve the carrier transport efficiency and passivation effect on interface defects in the fabricated perovskite / crystalline silicon tandem solar cell, thereby further improving the photoelectric conversion efficiency and stability of the perovskite / crystalline silicon tandem solar cell, in a preferred embodiment, step S6 is further included between step S7: a transparent conductive oxide layer 800 is prepared on the surface of the second carrier transport layer 600 away from the crystalline silicon base cell 100; the transparent conductive oxide layer 800 is conformally fitted to the crystalline silicon base cell 100.
[0084] In order to reduce light reflection loss and further improve the photoelectric conversion efficiency of the fabricated perovskite / crystalline silicon tandem solar cell, in a preferred embodiment, step S7 further includes: preparing an antireflection layer 900 on the surface of the metal electrode layer 700 away from the crystalline silicon base cell 100; the antireflection layer 900 is conformally fitted to the crystalline silicon base cell 100.
[0085] The present application will be further described in detail below with reference to specific embodiments, which should not be construed as limiting the scope of protection claimed in the present application.
[0086] Example 1
[0087] A method for fabricating a perovskite / crystalline silicon tandem solar cell specifically includes the following steps:
[0088] (1) Prepare a crystalline silicon bottom cell 100 with a pyramid-shaped textured surface (Zhejiang Aiko Solar Energy Technology Co., Ltd., heterojunction half-cell solar cell, specification 210mm×105mm) for later use;
[0089] (2) Preparation of tunneling layer 200: ITO was deposited on the conductive side of the crystalline silicon bottom cell 100 by magnetron sputtering to obtain a tunneling layer 200 with a thickness of 15 nm; wherein, the magnetron sputtering power was 40 W, the time was 5 min, the vacuum degree was 0.5 Pa, and the argon flow rate was 400 sccm.
[0090] (3) Preparation of self-assembled monolayer (SAM layer): 5g of poly-[4-(9H-carbazole-9-yl)butyl]phosphonic acid was mixed with 95g of isopropanol solvent to obtain ink with a mass concentration of 5wt%. Poly-[4-(9H-carbazole-9-yl)butyl]phosphonic acid was deposited on the surface of the tunneling layer 200 away from the crystalline silicon bottom cell 100 by inkjet printing to obtain a SAM layer with a thickness of 2nm;
[0091] (4) Preparation of perovskite active layer 400: 10g FA 0.6 MA 0.1 Cs 0.3 PbI 0.8 Br 0.2 The perovskite active material was mixed with 90g of a mixed solvent of dimethyl sulfoxide (DMSO) and N,N-dimethylformamide (DMF) (DMSO to DMF volume ratio of 25:75) to obtain a perovskite ink with a mass concentration of 10wt%. A perovskite active layer 400 with a pyramidal textured structure was prepared on the surface of the SAM layer away from the crystalline silicon bottom cell 100 by inkjet printing. The thickness of the perovskite active layer 400 was 750nm, the band gap was 1.68eV, and the average height of its pyramidal textured structure was 1.3μm.
[0092] (5) Preparation of interface functional layer 500: 0.05g of alumina (average particle size of 30nm) and 9.95g of acetic acid are mixed to obtain a first mixture with a mass concentration of 0.5wt%; the first mixture is sprayed onto the surface of the perovskite active layer 400 away from the crystalline silicon bottom cell 100 using an ultrasonic spraying device. Within 30s after the first mixture is deposited, the first drying is performed at 22℃ for 120s using a vacuum crystallizer to remove the acetic acid solvent, and an interface functional layer 500 with a thickness of 20nm is obtained; wherein, the distance between the nozzle and the perovskite active layer 400 in the ultrasonic spraying device is 5cm, the pressure is 1kPa, the flow rate is 0.2mL / min, the moving speed is 80mm / s, the ultrasonic frequency is 50kHz, and the power is 2W;
[0093] (6) Preparation of electron transport layer: 0.05g solvent-based tin oxide nanoparticles (Sofab Inks Ltd., Tinfab) were mixed with 9.95g acetic acid to obtain a second mixture with a mass concentration of 0.5wt%; the second mixture was sprayed onto the surface of the interface functional layer 500 away from the crystalline silicon bottom cell 100 using an ultrasonic spraying device. Within 30s after the second mixture was deposited, a second drying was performed at 25°C for 90s using a vacuum crystallizer to remove the acetic acid solvent and obtain a SnO2 layer with a thickness of 30nm; wherein, the distance between the nozzle and the interface functional layer 500 in the ultrasonic spraying device was 8cm, the pressure was 3kPa, the flow rate was 0.5mL / min, the moving speed was 100mm / s, the ultrasonic frequency was 80kHz, and the power was 10W;
[0094] (7) Preparation of transparent conductive oxide layer 800: IZO was deposited on the side of SnO2 layer away from crystalline silicon bottom cell 100 by magnetron sputtering to obtain an IZO layer with a thickness of 20nm; wherein, the magnetron sputtering power was 35W, the time was 5min, the vacuum degree was 0.8Pa, and the argon flow rate was 250sccm.
[0095] (8) Preparation of metal electrode layer 700: Ag metal grid lines are deposited on the surface of transparent conductive oxide layer 800 away from crystalline silicon bottom cell 100 by screen printing to obtain metal electrode layer 700 with a thickness of 5 μm.
[0096] (9) Preparation of antireflection layer 900: MgF2 is deposited on the surface of the metal electrode layer 700 away from the crystalline silicon bottom cell 100 by vacuum evaporation at a deposition rate of 0.5%. An antireflection layer 900 with a thickness of 150 nm was obtained.
[0097] A schematic diagram of the stacked structure of the perovskite / crystalline silicon tandem solar cell prepared in Example 1 is shown below. Figure 2 As shown, it includes a crystalline silicon bottom cell 100, a tunneling layer 200, a SAM layer, a perovskite active layer 400, an interface functional layer 500, a SnO2 layer, an IZO layer, a metal electrode layer 700, and an antireflection layer 900, which are stacked sequentially.
[0098] Example 2
[0099] The difference from Example 1 is that in step (5), an equal weight of silicon dioxide (with an average particle size of 5 nm) is used to replace the aluminum oxide in Example 1 to obtain an interface functional layer 500 with a thickness of 15 nm; the remaining steps are the same as in Example 1.
[0100] Example 3
[0101] The difference from Example 1 is that in step (5), an equal weight of zirconium oxide (with an average particle size of 25 nm) is used to replace the alumina in Example 1 to obtain an interface functional layer 500 with a thickness of 35 nm; the remaining steps are the same as in Example 1.
[0102] Example 4
[0103] The difference from Example 1 is that in step (5), 3g of alumina is mixed with 97g of acetic acid solvent to obtain a first mixture with a mass concentration of 0.01wt%, and an interface functional layer 500 with a thickness of 40nm is prepared; the remaining steps are the same as in Example 1.
[0104] Example 5
[0105] The difference from Example 1 is that in step (5), 10g of alumina is mixed with 90g of acetic acid solvent to obtain a first mixture with a mass concentration of 5wt%, and an interface functional layer 500 with a thickness of 20nm is prepared; the remaining steps are the same as in Example 1.
[0106] Example 6
[0107] The difference from Example 1 is that in step (5), 0.06g of alumina is mixed with 0.94g of acetic acid solvent to obtain a first mixture with a mass concentration of 6wt%, and an interface functional layer 500 with a thickness of 75nm is prepared; the remaining steps are the same as in Example 1.
[0108] Example 7
[0109] The difference from Example 1 is that in step (6), C is deposited on the surface of the interface functional layer 500 obtained in step (5) away from the crystalline silicon bottom cell 100 using vacuum evaporation. 60 The deposition rate was 1.3. A C layer with a thickness of 30 nm was obtained. 60 Layer, and in step (7), in C 60 A transparent conductive oxide layer 800 is prepared on the side of the layer away from the crystalline silicon base cell 100; the remaining steps are the same as in Example 1.
[0110] The electron transport layer in Example 7 is made of C. 60 Production costs are relatively high.
[0111] Example 8
[0112] The difference from Example 1 is that in step (5), the distance between the nozzle and the interface functional layer 500 in the ultrasonic spraying equipment is 5cm, the pressure is 1kPa, the flow rate is 0.2mL / min, the moving speed is 80mm / s, the ultrasonic frequency is 50kHz, and the power is 1W, so that an interface functional layer 500 with a thickness of 45nm is obtained; the remaining steps are the same as in Example 1.
[0113] Example 9
[0114] The difference from Example 1 is that in step (5), the distance between the nozzle and the interface functional layer 500 in the ultrasonic spraying equipment is 10cm, the pressure is 5kPa, the flow rate is 1mL / min, the moving speed is 120mm / s, the ultrasonic frequency is 120kHz, and the power is 15W, so that an interface functional layer 500 with a thickness of 50nm is obtained; the remaining steps are the same as in Example 1.
[0115] Example 10
[0116] The difference from Example 1 is that in step (5), the distance between the nozzle and the interface functional layer 500 in the ultrasonic spraying equipment is 15cm, the pressure is 0.5kPa, the flow rate is 0.1mL / min, the moving speed is 130mm / s, the ultrasonic frequency is 40kHz, and the power is 0.5W, so that an interface functional layer 500 with a thickness of 55nm is obtained; the remaining steps are the same as in Example 1.
[0117] Comparative Example 1
[0118] The difference from Example 1 is that in step S5, SnO2 material is deposited on the surface of the perovskite active layer 400 obtained in step (4) away from the crystalline silicon bottom cell 100 using atomic layer deposition, with a deposition rate of 0.45. A buffer layer with a thickness of 15 nm was obtained; the remaining steps were the same as in Example 1.
[0119] The perovskite / crystalline silicon tandem solar cell prepared in Comparative Example 1 did not have an interface functional layer 500 introduced.
[0120] Photovoltaic performance tests were conducted on the perovskite / crystalline silicon tandem solar cells prepared in all the embodiments and comparative examples of this application. The effective area of the devices was 1 cm². 2 At 100mW / cm 2 Under simulated sunlight conditions, the JV curves of perovskite / crystalline silicon tandem solar cells were tested using a WAVELABS brand perovskite tandem solar cell IV tester (model SINUS-220). The stability test conditions were as follows: the perovskite / crystalline silicon tandem solar cells prepared in all the above examples and comparative examples were continuously irradiated with air (relative humidity 5-10%RH) and AM1.5 light. The test results are shown in Table 1.
[0121] Table 1
[0122]
[0123] As can be seen from the above description, the embodiments of this application achieve the following technical effects:
[0124] Comparing Example 1 and Comparative Example 1, it can be seen that, compared with the traditional interface buffer layer, this application introduces an interface functional layer 500 between the perovskite active layer 400 and the second carrier transport layer 600, and uses a specific type of metal oxide as the material of the interface functional layer 500. This can effectively improve the chemical stability of the interface functional layer 500, and to a certain extent suppress ion migration in the perovskite active layer 400, thereby improving interface stability. At the same time, it can also passivate the surface defects between the perovskite active layer 400 and the second carrier transport layer 600, reduce non-radiative recombination losses, thereby reducing the interface series resistance, improving the carrier transport efficiency, and thus improving the photoelectric conversion efficiency and stability of the perovskite / crystalline silicon tandem solar cell.
[0125] Comparing Examples 1, 4 to 6, it can be seen that, compared to other ranges, limiting the mass concentration of the first mixture used to prepare the interface functional layer 500 to the preferred range described above in this application is beneficial to improving the dispersion uniformity of the metal oxide, and beneficial to improving the interfacial interaction between the interface functional layer 500 and the perovskite active layer 400, resulting in a uniform interface functional layer 500 with a more suitable thickness. This is beneficial to suppressing ion migration in the perovskite active layer 400, reducing carrier recombination, lowering the interfacial series resistance, and improving the carrier transport efficiency, thereby improving the photoelectric conversion efficiency and stability of the perovskite / crystalline silicon tandem solar cell.
[0126] Comparing Examples 1 and 7, it can be seen that compared to C 60 Using solvent-based tin oxide nanoparticles as the material for the electron transport layer in this application enables solution-based preparation of the electron transport layer. This also improves the stability of the electron transport layer in humid environments. Depositing the electron transport layer made from solvent-based tin oxide nanoparticles onto the surface of the perovskite active layer 400 can completely replace C. 60 The film layer plays a crucial role and significantly reduces production costs; simultaneously, compared to perovskite active layers 400 and C... 60 The perovskite active layer 400 and the tin oxide nanoparticle film have stronger interfacial bonding, which helps to improve the stability of perovskite / crystalline silicon tandem solar cells.
[0127] Comparing Examples 1, 8 to 10, it can be seen that, compared with other ranges, limiting the process parameters in the spraying process to the above-mentioned preferred range of this application is beneficial to improving the spraying efficiency and improving the interfacial interaction between the interface functional layer 500 and the perovskite active layer 400, resulting in an interface functional layer 500 with a more uniform thickness and improving its film quality, thereby improving the photoelectric conversion efficiency and stability of the perovskite / crystalline silicon tandem solar cell.
[0128] It should be noted that the terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such terms can be used interchangeably where appropriate so that the embodiments of this application described herein can be implemented, for example, in a sequence other than those described herein.
[0129] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.
Claims
1. A perovskite / crystalline silicon tandem solar cell, characterized in that, The perovskite / crystalline silicon tandem solar cell comprises a crystalline silicon base cell (100), a tunneling layer (200), a first carrier transport layer (300), a perovskite active layer (400), an interface functional layer (500), a second carrier transport layer (600), and a metal electrode layer (700) stacked sequentially. The interface functional layer (500) is made of a metal oxide, and the metal element in the metal oxide is selected from one or more elements in Group IIIA, Group IIIB, Group IVA, and Group IVB. The crystalline silicon base cell (100) has a pyramidal textured surface structure. The tunneling layer (200), the first carrier transport layer (300), the perovskite active layer (400), the interface functional layer (500), and the second carrier transport layer (600) are all conformally aligned with the crystalline silicon base cell (100).
2. The perovskite / crystalline silicon tandem solar cell according to claim 1, characterized in that, The metallic element is selected from one or more of the group consisting of Al, Si, Zr, Y, and La; Preferably, the metal oxide is selected from one or more of the group consisting of aluminum oxide, silicon dioxide, zirconium dioxide, yttrium oxide, and lanthanum oxide; Preferably, the thickness of the interface functional layer (500) is 20-200 nm, more preferably 30-50 nm.
3. The perovskite / crystalline silicon tandem solar cell according to claim 1, characterized in that, The average height of the pyramid-shaped textured structure of the perovskite active layer (400) is 1.5 to 2.5 μm; the thickness of the perovskite active layer (400) is 750 to 1250 nm, preferably 750 to 900 nm. Preferably, the interface functional layer (500) has a coverage of 85-98% on the surface of the perovskite active layer (400); Preferably, the band gap of the perovskite active layer (400) is 1.55–1.75 eV, more preferably 1.65–1.68 eV; Preferably, the material of the perovskite active layer (400) is ABX3; Wherein, A is selected from CH3NH3 + NH=CHNH3 + and Cs + One or more of the groups, where B is selected from Pb 2+ and / or Sn 2+ X is selected from Cl - ,Br - and I - One or more of the groups.
4. The perovskite / crystalline silicon tandem solar cell according to any one of claims 1 to 3, characterized in that, The first carrier transport layer (300) is a hole transport layer, and the second carrier transport layer (600) is an electron transport layer; Preferably, the thickness of the hole transport layer is 2–20 nm, more preferably 2–5 nm; Preferably, the hole transport layer is a self-assembled monolayer; the material of the hole transport layer is selected from one or more of the following groups: poly-[4-(9H-carbazole-9-yl)butyl]phosphonic acid, [4-(9H-carbazole-9-yl)butyl]phosphonic acid, (4-(7H-dibenzo[c,g]carbazole-7-yl)phenyl)phosphonic acid, (2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl)phosphonic acid, (4-(3,11-dimethoxy-7H-dibenzo[c,g]carbazole-7-yl)butyl)phosphonic acid, and (4-(3,6-dibromo-9H-carbazole-9-yl)butyl)phosphonic acid. Preferably, the thickness of the electron transport layer is 15–35 nm; Preferably, the electron transport layer is made of solvent-based tin oxide nanoparticles.
5. The perovskite / crystalline silicon tandem solar cell according to claim 4, characterized in that, The crystalline silicon bottom cell (100) is selected from HJT cells, BC cells or TOPCon cells; Preferably, the thickness of the tunneling layer (200) is 5–20 nm; Preferably, the material of the tunneling layer (200) is selected from indium tin oxide and / or indium zinc oxide; Preferably, the thickness of the metal electrode layer (700) is 5–30 μm; Preferably, the material of the metal electrode layer (700) is selected from one or more of the group consisting of Ag, Cu and Al.
6. The perovskite / crystalline silicon tandem solar cell according to any one of claims 1 to 5, characterized in that, A transparent conductive oxide layer (800) is further disposed between the second carrier transport layer (600) and the metal electrode layer (700); the transparent conductive oxide layer (800) is conformally fitted to the crystalline silicon bottom cell (100); Preferably, the thickness of the transparent conductive oxide layer (800) is 15–30 nm; Preferably, the material of the transparent conductive oxide layer (800) is selected from indium zinc oxide and / or indium tin oxide; Preferably, an anti-reflection layer (900) is further provided on the side of the metal electrode layer (700) away from the crystalline silicon bottom cell (100); the anti-reflection layer (900) is conformally fitted to the crystalline silicon bottom cell (100); More preferably, the thickness of the antireflective layer (900) is 100-200 nm; More preferably, the material of the antireflective layer (900) is selected from magnesium fluoride and / or silicon dioxide.
7. A method for preparing a perovskite / crystalline silicon tandem solar cell according to any one of claims 1 to 6, characterized in that, The preparation method includes: Step S1: Prepare a crystalline silicon bottom cell (100) for later use; the crystalline silicon bottom cell (100) has a pyramid-shaped textured surface structure; Step S2: A tunneling layer (200) is prepared on one side of the conductive surface of the crystalline silicon bottom cell (100). Step S3: A first carrier transport layer (300) is prepared on the surface of the tunneling layer (200) away from the crystalline silicon bottom cell (100). Step S4: A perovskite active layer (400) is prepared on the surface of the first carrier transport layer (300) away from the crystalline silicon bottom cell (100). Step S5: The first mixture containing metal oxide is sprayed onto the surface of the perovskite active layer (400) away from the crystalline silicon bottom cell (100), and after the first drying, an interface functional layer (500) is obtained; the metal element in the metal oxide is selected from one or more elements in the group consisting of elements in Group IIIA, Group IIIB, Group IVA and Group IVB. Step S6: A second carrier transport layer (600) is prepared on the surface of the interface functional layer (500) away from the crystalline silicon bottom cell (100). Step S7: A metal electrode layer (700) is prepared on one side surface of the second carrier transport layer (600) to obtain the perovskite / crystalline silicon tandem solar cell; The tunneling layer (200), the first carrier transport layer (300), the perovskite active layer (400), the interface functional layer (500), and the second carrier transport layer (600) are all conformally oriented with the crystalline silicon bottom cell (100).
8. The method for fabricating a perovskite / crystalline silicon tandem solar cell according to claim 7, characterized in that, Step S5 further includes mixing the metal oxide with a first organic solvent to obtain the first mixture; Preferably, in the first mixture, the mass concentration of the metal oxide is 0.01–5 wt%; Preferably, the average particle size of the metal oxide is 5–30 nm; Preferably, the metal element in the metal oxide is selected from one or more of the group consisting of Al, Si, Zr, Y and La; more preferably, the metal oxide is selected from one or more of the group consisting of aluminum oxide, silicon dioxide, zirconium dioxide, yttrium oxide and lanthanum oxide. Preferably, the first organic solvent is selected from alcohol solvents and / or acid solvents; more preferably, the first organic solvent is selected from one or more of the group consisting of acetic acid, propionic acid, ethanol, isopropanol, n-butanol or isooctanol. Preferably, the distance between the spray nozzle and the perovskite active layer (400) used in the spraying process is 5-10 cm, the pressure is 1-5 kPa, the flow rate is 0.2-1 mL / min, and the moving speed is 80-120 mm / s; Preferably, in step S5, the spraying is performed using an ultrasonic spraying method, with an ultrasonic frequency of 50-120 kHz and a power of 1-15 W. Preferably, the first drying is performed using a first heating device at a temperature of 100–120°C for 5–15 minutes; or, the first drying is performed using a vacuum crystallizer or an air knife at a temperature of 18–25°C for 30–120 seconds.
9. The method for fabricating a perovskite / crystalline silicon tandem solar cell according to claim 7, characterized in that, The second carrier transport layer (600) is an electron transport layer; Preferably, step S6 includes: mixing solvent-based tin oxide nanoparticles with a second organic solvent to obtain a second mixture; spraying the second mixture onto the surface of the interface functional layer (500) away from the crystalline silicon bottom cell (100), and obtaining the electron transport layer after a second drying; Preferably, in the second mixture, the mass concentration of the solvent-based tin oxide nanoparticles is 0.5–2 wt%. Preferably, the solvent-based tin oxide nanoparticles have an average particle size of 5–20 nm; Preferably, the second organic solvent is selected from acid solvents and / or alcohol solvents; more preferably, the second organic solvent is selected from one or more of the group consisting of acetic acid, isopropanol, n-butanol and isooctyl alcohol. Preferably, in step S6, the spraying is performed using ultrasonic spraying or inkjet printing. Preferably, the second drying is performed using a second heating device at a temperature of 100–120°C for 5–15 minutes; or, the second drying is performed using a vacuum crystallizer or an air knife at a temperature of 18–25°C for 30–120 seconds.
10. The method for preparing a perovskite / crystalline silicon tandem solar cell according to any one of claims 7 to 9, characterized in that, Between step S6 and step S7, a transparent conductive oxide layer (800) is further prepared on the surface of the second carrier transport layer (600) away from the crystalline silicon base cell (100); the transparent conductive oxide layer (800) is conformally oriented to the crystalline silicon base cell (100); Preferably, step S7 further includes: preparing an antireflection layer (900) on the surface of the metal electrode layer (700) away from the crystalline silicon base cell (100); the antireflection layer (900) is conformally fitted to the crystalline silicon base cell (100).