Perovskite tandem solar cell and preparation method thereof

Abstract

The present disclosure relates to the technical field of solar cells, and discloses a perovskite laminated solar cell and a preparation method thereof, which comprises: sequentially forming a charge recombination layer and a first transport layer on a bottom cell; forming a plurality of isolation lines on the first transport layer, the plurality of isolation lines respectively extend along a first direction and a second direction to be connected into a grid-shaped structure, and the isolation lines isolate the surface of the first transport layer into a plurality of array-arranged isolation regions; forming a plurality of perovskite absorption units in the plurality of isolation regions, the plurality of perovskite absorption units are array-arranged to form a perovskite absorption layer, and the thickness of the perovskite absorption unit is less than the height of the isolation line; removing the plurality of isolation lines to form a grid-shaped groove between adjacent perovskite absorption units; and sequentially forming a second transport layer and a transparent conductive layer on the perovskite absorption layer. The present disclosure can improve the film formation quality of the perovskite absorption unit in the perovskite laminated solar cell, and at the same time improve the carrier transport efficiency of the perovskite absorption layer.

Description

Technical Field

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

[0002] In related technologies, the perovskite absorber layer in perovskite tandem solar cells is formed by large-area whole-surface growth, which leads to poor stability during the crystallization growth process. This results in a large number of grain boundary defects, pinholes and residual stress, affecting the film quality and carrier transport efficiency of the perovskite absorber layer. Furthermore, the production cost is high, making mass production difficult.

[0003] The perovskite absorber layer covering the entire surface is prone to lateral transport of charge carriers during operation, which reduces the effective longitudinal transport of charge carriers, thereby reducing the carrier transport and collection efficiency in the perovskite tandem solar cell and affecting the cell conversion efficiency.

[0004] Therefore, a solution is needed to improve the film quality and stability of the perovskite absorber layer, reduce the lateral transport of charge carriers in the perovskite absorber layer, and improve the efficiency and performance of the battery. Summary of the Invention

[0005] This disclosure provides a perovskite tandem solar cell and its preparation method, which solves the problems in related technologies where the perovskite absorber layer has poor crystallization stability, many defects, and poor film quality during large-area whole-surface crystallization growth, thus affecting the cell conversion efficiency.

[0006] In a first aspect, this disclosure provides a method for fabricating a perovskite tandem solar cell, the method comprising: A bottom cell is provided, on which a charge recombination layer and a first transport layer are sequentially formed; Multiple isolation lines are formed on the surface of the first transport layer on the side opposite to the charge recombination layer. The multiple isolation lines extend and connect along the first direction and the second direction to form a grid structure. The isolation lines isolate the surface of the first transport layer into several arrayed isolation regions. Multiple perovskite absorption units are formed in multiple isolation areas, and the array of multiple perovskite absorption units forms a perovskite absorption layer. Multiple isolation lines are removed to form a grid-like groove between adjacent perovskite absorber units; A second transport layer and a transparent conductive layer are sequentially formed on the surface of the perovskite absorber layer facing away from the first transport layer.

[0007] The method for fabricating a perovskite tandem solar cell disclosed herein includes the following aspects: First, multiple isolation lines with a grid-like structure are first formed, and then perovskite absorber units are formed in multiple isolation regions between the isolation lines. This allows for small-area crystallization of the perovskite absorber units within each isolation region, improving the film quality and stability of the perovskite absorber units, reducing defects within the perovskite absorber units, and avoiding damage caused by laser grooving of the perovskite absorber layer. This improves the film quality and carrier transport efficiency of the perovskite absorber units. Furthermore, the isolation lines can space multiple perovskite absorber units, ensuring that the perovskite absorber units are independent of each other and preventing contact between adjacent perovskite absorber units. Second, after the isolation lines are removed, the multiple perovskite absorber units are arrayed, which can prevent lateral carrier transport and improve the effective longitudinal carrier transport efficiency, thereby improving the carrier transport and collection efficiency in the perovskite absorber layer and thus improving the cell conversion efficiency. Third, a first transport layer is disposed across the entire bottom of the perovskite absorber layer, which can collect carriers in each perovskite absorber unit, increasing electron collection efficiency and thus improving the cell efficiency.

[0008] In one alternative embodiment, multiple isolation lines are formed on the surface of the first transport layer opposite to the charge recombination layer, including: A patterned isolation adhesive layer is formed on the surface of the first transport layer opposite to the charge composite layer using a printing process. The pattern of the isolation adhesive layer is a grid structure. The release adhesive layer is cured to obtain multiple release lines.

[0009] The method for fabricating perovskite tandem solar cells disclosed herein directly forms a patterned insulating adhesive layer through a printing process. After curing, it can form multiple insulating lines in a grid structure, which can simplify the fabrication process, reduce process costs, and improve the fabrication efficiency of the cells.

[0010] In one alternative embodiment, multiple isolation lines are formed on the surface of the first transport layer opposite to the charge recombination layer, including: An insulating adhesive layer is formed on the surface of the first transport layer on the side opposite to the charge recombination layer. The release adhesive layer is selectively cured, forming multiple grid-like release lines in the cured area; multiple uncured areas are isolated between the multiple release lines; Remove the release adhesive layer from the uncured areas, and multiple isolation lines isolate the surface of the first transport layer into several arrayed isolation areas, exposing the surface of the first transport layer in the isolation areas.

[0011] The method for fabricating perovskite tandem solar cells disclosed herein first forms a full-surface insulating adhesive layer, then selectively cures the insulating adhesive layer, forming multiple grid-like distributed isolation lines in the cured area, and finally removes the uncured insulating adhesive layer to obtain multiple isolation lines with a grid structure, as well as multiple array-arranged isolation regions located between the isolation lines. This method can improve the precision and dimensional accuracy of the isolation lines, enhance the clarity and smoothness of the isolation line boundaries, thereby improving the dimensional accuracy of the subsequently formed perovskite absorber units, reducing the sidewall roughness of the perovskite absorber units, and thus improving the electron transport efficiency of the perovskite absorber layer.

[0012] In one alternative embodiment, the material of the release adhesive layer is a photocurable adhesive; the release adhesive layer is suitable for laser curing. Light-cured adhesives include acrylonitrile-butadiene-styrene resins.

[0013] The method for fabricating perovskite tandem solar cells disclosed herein uses photocurable adhesive as the insulating layer and employs laser to cure the insulating layer, which can improve process efficiency and avoid damage to other film layers.

[0014] In one alternative implementation, multiple perovskite absorber units are formed within multiple isolation regions, including: A perovskite precursor solution was filled into the isolation area using an air knife-assisted coating method, with the height of the perovskite precursor solution being less than the height of the isolation line. The perovskite precursor solution within the isolation area is crystallized to form multiple perovskite absorption units; the thickness of the perovskite absorption unit is less than the height of the isolation line.

[0015] The method for fabricating perovskite tandem solar cells disclosed herein includes, on the one hand, firstly, filling the perovskite precursor solution in the isolation region using an air knife-assisted coating method. The solution, after being swept by the air knife, can uniformly fill the isolation region, thereby improving the high uniformity of the perovskite precursor solution in multiple isolation regions. On the other hand, the perovskite precursor solution in the isolation region is subjected to crystallization treatment to form multiple perovskite absorber units. This allows for small-area crystallization of the perovskite precursor solution, improving the film quality of the perovskite absorber units and thus increasing the cell efficiency.

[0016] In one optional embodiment, the crystallization process is evaporative crystallization, during which nitrogen gas is used to purge the surface of the perovskite precursor solution; the crystallization temperature is 50°C to 70°C. The perovskite precursor solution includes methylamine lead iodide, lead bromide, N,N-dimethylformamide, and dimethyl sulfoxide, wherein methylamine lead iodide and lead bromide are solutes, and N,N-dimethylformamide and dimethyl sulfoxide are solvents.

[0017] The method for fabricating perovskite tandem solar cells disclosed herein employs a low-temperature (50℃~70℃) evaporation crystallization process to form multiple perovskite absorber units. This effectively controls the crystallization rate and reduces grain boundary defects within the perovskite film. Simultaneously, nitrogen gas is used to purge the surface of the perovskite precursor solution, removing excess solvent during crystallization and improving the growth rate and film quality of the perovskite absorber units. Furthermore, by controlling the proportions of the components in the perovskite precursor solution, the quality and speed of perovskite film formation can be improved.

[0018] In one alternative embodiment, the isolation line is adapted to dissolve in a nonpolar solvent; Removing multiple isolation lines includes: removing isolation lines based on nonpolar solvents to obtain several mutually isolated perovskite absorber units arranged in an array; the nonpolar solvent is suitable for dissolving the isolation lines; the nonpolar solvent includes n-heptane or toluene.

[0019] The method for fabricating perovskite tandem solar cells disclosed herein uses a non-polar solvent to remove the isolation lines, which can dissolve and remove the isolation lines while avoiding damage to the perovskite absorber layer, thus completing the final shaping of the isolation structure, avoiding lateral transport of charge carriers between perovskite absorber units, and improving the longitudinal transport rate and collection efficiency of charge carriers.

[0020] In one alternative embodiment, the bottom cell is a tunneling oxide passivated contact solar cell; Provides a base battery, including: A silicon wafer is provided, comprising a front side and a back side arranged opposite to each other; A tunneling oxide layer, a doped polysilicon layer, and a passivation layer are sequentially formed on the back side of the silicon wafer. A charge recombination layer and a first transport layer are sequentially formed on the bottom cell, including: forming a charge recombination layer and a first transport layer sequentially on the front side of the silicon wafer.

[0021] The method for fabricating perovskite tandem solar cells disclosed herein uses a tunneling oxide passivated contact solar cell as the base cell, which can form a perovskite-tunneling oxide passivated contact tandem solar cell.

[0022] In one optional embodiment, the silicon wafer is an N-type silicon wafer, the doped polysilicon layer is an N-type doped polysilicon layer, the first transport layer is an electron transport layer, and the second transport layer is a hole transport layer. Alternatively, the silicon wafer is a P-type silicon wafer, and the doped polysilicon layer is a P-type doped polysilicon layer; the first transport layer is a hole transport layer, and the second transport layer is an electron transport layer; The electron transport layer is formed using a chemical vapor deposition process, and the material of the electron transport layer includes zinc oxide; the hole transport layer is formed using a magnetron sputtering process or a solution spin coating process, and the material of the hole transport layer includes nickel oxide.

[0023] The method for fabricating perovskite tandem solar cells disclosed herein can form different types of perovskite tandem cells according to requirements, improving design flexibility and broadening application scenarios. Using chemical vapor deposition to form the electron transport layer can improve the film quality and fabrication efficiency of the electron transport layer; using magnetron sputtering or solution spin coating to form the hole transport layer can improve the film quality and fabrication efficiency of the hole transport layer.

[0024] In an optional embodiment, after the second transport layer and the transparent conductive layer are sequentially formed on the surface of the perovskite absorber layer facing away from the first transport layer, the fabrication method further includes: A first electrode is formed on the side of the transparent conductive layer opposite to the second transport layer; A second electrode is formed on the side of the bottom cell facing away from the first transport layer.

[0025] The method for fabricating perovskite tandem solar cells disclosed herein forms a first electrode and a second electrode on both sides of the cell, which can improve the conductive structure and ensure the efficient collection and smooth extraction of photogenerated carriers.

[0026] Secondly, this disclosure also provides a perovskite tandem solar cell, which is prepared by the method for preparing a perovskite tandem solar cell according to the first aspect or any corresponding embodiment described above. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the specific embodiments of this disclosure or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0028] Figure 1 This is a schematic flowchart of a method for fabricating a perovskite tandem solar cell according to an embodiment of the present disclosure; Figure 2 This is a schematic diagram of the bottom cell structure in a method for fabricating a perovskite tandem solar cell according to an embodiment of this disclosure; Figure 3 This is a schematic diagram of the structure of forming a charge recombination layer and a first transport layer in a method for preparing a perovskite tandem solar cell according to an embodiment of this disclosure; Figure 4A This is a schematic diagram of the structure forming the isolation line in a method for fabricating a perovskite tandem solar cell according to an embodiment of this disclosure; Figure 4BThis is a top view of the structure formed by the isolation line in a method for fabricating a perovskite tandem solar cell according to an embodiment of this disclosure; Figure 4A Is Figure 4B Schematic diagram of the cross-sectional structure of surface AA in the middle; Figure 5A This is a schematic diagram of the structure of the perovskite absorber layer formed in a method for preparing a perovskite tandem solar cell according to an embodiment of this disclosure; Figure 5B This is a top view schematic diagram of the perovskite absorber layer formed in a method for preparing a perovskite tandem solar cell according to an embodiment of this disclosure; Figure 5A Is Figure 5B Schematic diagram of the cross-sectional structure of surface AA in the middle; Figure 6 This is a schematic diagram of the structure for removing the isolation lines in a method for fabricating a perovskite tandem solar cell according to an embodiment of this disclosure; Figure 7A This is a schematic diagram of the structure in which a second transport layer and a transparent conductive layer are formed in a method for fabricating a perovskite tandem solar cell according to an embodiment of this disclosure; Figure 7B This is a schematic diagram of the structure of forming a second transport layer and a transparent conductive layer in another method for preparing a perovskite tandem solar cell according to an embodiment of this disclosure; Figure 7C This is a schematic diagram of the structure of forming a second transport layer and a transparent conductive layer in another method for preparing a perovskite tandem solar cell according to an embodiment of this disclosure.

[0029] Figure label: 100. Base cell; 10. Silicon wafer; 11. Tunneling oxide layer; 12. Doped polycrystalline silicon layer; 13. Passivation layer; 131. First passivation layer; 132. Second passivation layer; 20. Charge recombination layer; 31. First transport layer; 32. Perovskite absorption layer; 320. Perovskite absorption unit; 33. Second transport layer; 34. Transparent conductive layer; 40. Isolation line; 41. Groove; 50. Isolation region; 61. First electrode; 62. Second electrode. Detailed Implementation

[0030] The present disclosure will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present disclosure and not intended to limit it. Furthermore, it should be noted that, for ease of description, only the parts relevant to the present disclosure are shown in the drawings, not the entire structure. All other embodiments obtained by those skilled in the art based on the embodiments of the present disclosure without inventive effort are within the scope of protection of the present disclosure.

[0031] In the following description, descriptions of well-known structures and techniques are omitted to avoid unnecessarily obscuring the concepts of this disclosure. Various structural schematic diagrams according to embodiments of this disclosure are shown in the accompanying drawings. These drawings are not to scale, and some details are enlarged for clarity and may be omitted. The shapes of the various regions and layers shown in the drawings, as well as their relative sizes and positional relationships, are merely exemplary and may deviate from actual practices due to manufacturing tolerances or technical limitations. Furthermore, those skilled in the art can design regions / layers with different shapes, sizes, and relative positions as needed. In the context of this disclosure, when a layer / element is referred to as being "on" another layer / element, the layer / element may be directly on the other layer / element, or there may be an intermediate layer / element between them. Additionally, if a layer / element is "on" another layer / element in one orientation, then when the orientation is reversed, the layer / element may be "below" the other layer / element.

[0032] In related technologies, the perovskite absorber layer in perovskite tandem solar cells is formed using a large-area, whole-surface crystal growth method. This leads to poor stability during the crystallization growth process, resulting in numerous grain boundary defects, pinholes, and residual stress. These issues affect the film quality and carrier transport efficiency of the perovskite absorber layer, and also result in high production costs, making mass production difficult. Furthermore, the whole-surface perovskite absorber layer is prone to lateral carrier transport during operation, leading to reduced effective longitudinal carrier transport. This, in turn, reduces carrier transport and collection efficiency in the perovskite tandem solar cell, impacting the cell's conversion efficiency.

[0033] Although some solutions use laser grooving to cut the entire perovskite absorber layer into multiple smaller perovskite absorber layers to reduce lateral carrier transport, the laser grooving process will damage the perovskite absorber layer, affecting its performance and thus the battery conversion efficiency.

[0034] Therefore, a solution is needed to improve the film quality and stability of the perovskite absorber layer, reduce the lateral transport of charge carriers in the perovskite absorber layer, and improve the efficiency and performance of the battery.

[0035] This disclosure enables the preparation of perovskite thin films in a small, regionalized area by designing isolation lines, transforming the difficulty of large-area crystallization into small-area crystallization, which can greatly improve the film quality and ultimately improve battery efficiency.

[0036] like Figure 1 As shown, this embodiment provides a method for fabricating a perovskite tandem solar cell, which includes, but is not limited to, steps S101 to S105.

[0037] Step S101, provide a bottom battery 100, such as Figure 2 As shown, a charge recombination layer 20 and a first transport layer 31 are sequentially formed on the bottom battery 100, as follows: Figure 3 As shown.

[0038] In specific implementations, the bottom cell 100 can be a tunnel oxide passivated contact solar cell (TOPCon) or other crystalline silicon bottom cells suitable for fabricating tandem cells. The charge recombination layer 20 is used to recombine the charge in the bottom cell 100 with the subsequently formed top perovskite cell. The charge recombination layer 20 can be a transparent conductive oxide, such as indium tin oxide (ITO), fluorine-doped tin oxide (FTO), or aluminum-doped zinc oxide (AZO). The first transport layer 31 is an electron transport layer or a hole transport layer.

[0039] In step S102, multiple isolation lines 40 are formed on the surface of the first transport layer 31 on the side opposite to the charge recombination layer 20. These isolation lines 40 extend and connect along a first direction and a second direction, respectively, to form a mesh structure. The isolation lines 40 isolate the surface of the first transport layer 31 into several arrayed isolation regions 50, such as... Figure 4A and Figure 4B As shown.

[0040] In specific implementation, the first direction and the second direction intersect. Among the multiple isolation lines 40, some isolation lines 40 extend along the first direction, and others extend along the second direction. The multiple isolation lines 40 are interconnected to form a grid-like structure. At the same time, the area between the multiple isolation lines 40 is an isolation region 50. The multiple isolation lines 40 divide the surface of the first transmission layer 31 into several arrayed isolation regions 50.

[0041] Step S103: Multiple perovskite absorption units 320 are formed within multiple isolation regions 50, and the multiple perovskite absorption units 320 are arranged in an array to form a perovskite absorption layer 32; the thickness of the perovskite absorption unit 320 is less than the height of the isolation line 40, such as... Figure 5A and Figure 5B As shown.

[0042] In practice, a perovskite absorption unit 320 is formed in each isolation region 50, allowing the perovskite absorption unit 320 to grow and crystallize in a small area; multiple isolation regions 50 correspond one-to-one with multiple perovskite absorption units 320.

[0043] Step S104: Remove multiple isolation lines 40 and form a grid-like groove 41 between adjacent perovskite absorber units 320, such as... Figure 6 As shown.

[0044] In specific implementation, after removing multiple isolation lines 40, multiple grooves 41 are formed at the positions of the isolation lines 40. Each groove 41 exposes the surface of the first transport layer 31 between adjacent perovskite absorption units 320, thereby achieving separation between multiple perovskite absorption units 320 and avoiding lateral transport of charge carriers between perovskite absorption units 320.

[0045] In step S105, a second transport layer 33 and a transparent conductive layer 34 are sequentially formed on the surface of the perovskite absorber layer 32 facing away from the first transport layer 31, as follows: Figure 7A , Figure 7B and Figure 7C As shown.

[0046] In specific implementation, one of the first transport layer 31 and the second transport layer 33 is an electron transport layer, and the other is a hole transport layer. The transparent conductive layer 34 can be a TCO or similar material. The first transport layer 31, the perovskite absorber layer 32, the second transport layer 33, and the transparent conductive layer 34 constitute a perovskite solar cell, serving as the top cell of the tandem solar cell. The bottom cell 100 and the perovskite solar cell together form a perovskite tandem solar cell, with the top cell and bottom cell recombinating charges through the charge recombination layer 20.

[0047] The method for fabricating a perovskite tandem solar cell provided in this embodiment has two aspects. First, multiple isolation lines 40 with a grid structure are formed. Then, perovskite absorber units 320 are formed in multiple isolation regions 50 between the isolation lines 40. This allows for small-area crystallization of the perovskite absorber units 320 in each isolation region 50, improving the film quality and stability of the perovskite absorber units 320, reducing defects within the perovskite absorber units 320, and avoiding damage caused by laser grooving of the perovskite absorber layer 320. This improves the film quality and carrier transport efficiency of the perovskite absorber units 320. Furthermore, the isolation lines 40 can space multiple perovskite absorber units 320, preventing contact between adjacent perovskite absorber units 320. Second, after the isolation lines 40 are removed, the multiple perovskite absorber units 320 are arrayed, which avoids lateral carrier transport and improves the effective longitudinal carrier transport efficiency, thereby improving the carrier transport and collection efficiency in the perovskite absorber layer 32, and thus improving the cell conversion efficiency. Thirdly, the first transport layer 31 is disposed entirely below the perovskite absorption layer 32, which can collect the charge carriers in each perovskite absorption unit 320, increase the electron collection efficiency, and thus improve the battery efficiency.

[0048] In some alternative implementations, each perovskite absorber unit 320 completely fills the surface of the isolation region 50; the width of the perovskite absorber unit 320 is equal to the width of the isolation region 50.

[0049] In some alternative implementations, the thickness of the perovskite absorber unit 320 is less than the height of the isolation line 40, which can better space multiple perovskite absorber units 320 and avoid contact between adjacent perovskite absorber units 320.

[0050] In some alternative implementations, the material of the isolation line 40 is an insulating material.

[0051] In some alternative implementations, the first direction is perpendicular to the second direction, and the isolation region 50 is rectangular in shape.

[0052] In some alternative implementations, multiple perovskite absorber units 320 are arranged in parallel.

[0053] In some optional embodiments, multiple isolation lines 40 are formed on the surface of the first transport layer 31 opposite to the charge composite layer 20, including: forming a patterned isolation adhesive layer on the surface of the first transport layer 31 opposite to the charge composite layer 20 using a printing process, wherein the pattern of the isolation adhesive layer is a grid structure; and curing the isolation adhesive layer to obtain multiple isolation lines 40.

[0054] In practice, the shape of the graphic isolation adhesive layer is a grid-like structure formed by the extension and intersection of the first and second directions.

[0055] The perovskite tandem solar cell fabrication method provided in this embodiment directly forms a patterned insulating adhesive layer through a printing process. After curing, it can form multiple insulating lines 40 in a grid structure, which can simplify the fabrication process, reduce process costs, and improve the fabrication efficiency of the cell.

[0056] In some optional embodiments, multiple isolation lines 40 are formed on the surface of the first transport layer 31 facing away from the charge composite layer 20, including: forming a full-surface isolation adhesive layer on the surface of the first transport layer 31 facing away from the charge composite layer 20; selectively curing the isolation adhesive layer to form multiple grid-distributed isolation lines 40 in the cured area, with multiple arrayed uncured areas isolated between the multiple isolation lines 40; removing the isolation adhesive layer in the uncured areas, with the multiple isolation lines 40 isolating the surface of the first transport layer 31 into several arrayed isolation areas 50, with the isolation areas 50 exposing the surface of the first transport layer 31.

[0057] The method for fabricating a perovskite tandem solar cell provided in this embodiment first forms a full-surface insulating adhesive layer, then selectively cures the insulating adhesive layer, forming multiple grid-like distributed insulating lines 40 in the cured area, and finally removes the uncured insulating adhesive layer to obtain multiple grid-like insulating lines 40 and multiple array-arranged insulating regions 50 located between the insulating lines 40. This method can improve the precision and dimensional accuracy of the insulating lines 40, enhance the clarity and smoothness of the boundaries of the insulating lines 40, thereby improving the dimensional accuracy of the subsequently formed perovskite absorption unit 320, reducing the sidewall roughness of the perovskite absorption unit 320, and thus improving the electron transport efficiency of the perovskite absorption layer 32.

[0058] In some alternative embodiments, the release liner is made of a photocurable adhesive. Selective curing of the release liner includes using a laser to selectively cure it. Removal of the uncured areas of the release liner includes using water to remove it.

[0059] The perovskite tandem solar cell fabrication method provided in this embodiment employs laser selective curing of the insulating adhesive layer, which can precisely define the edge lines between adjacent insulating regions 50, providing a reliable microscopic framework for the subsequent crystallization of the perovskite absorber units 320. Water is used to remove the insulating adhesive layer in uncured areas, enabling the removal of excess uncured adhesive layer in a non-destructive and environmentally friendly manner, thereby forming an array of regularly arranged perovskite growth micro-regions (i.e., insulating regions 50) in the uncured areas.

[0060] In some alternative implementations, the width of the isolation line 40 is 10μm to 50μm, such as 10μm, 20μm, 30μm, 40μm or 50μm.

[0061] In some alternative embodiments, the height of the isolation line 40 is 100μm to 200μm, such as 100μm, 120μm, 150μm, 180μm or 200μm; the thickness of the perovskite absorption unit 320 is 100nm to 500nm, such as 100nm, 200nm, 300nm, 400nm or 500nm.

[0062] The perovskite tandem solar cell fabrication method provided in this embodiment has an isolation line 40 with a height more than 10 times greater than the thickness of the perovskite absorber unit 320, so as to better space multiple perovskite absorber units 320, ensure that the perovskite absorber units 320 are independent of each other, and facilitate the subsequent removal of the isolation line 40, thereby improving process compatibility.

[0063] In some alternative embodiments, the material of the release adhesive layer is a photocurable adhesive; the release adhesive layer is suitable for laser curing.

[0064] In some alternative embodiments, the light-curing adhesive includes an acrylonitrile-butadiene-styrene resin.

[0065] The perovskite tandem solar cell fabrication method provided in this embodiment uses photocurable adhesive as the isolation layer and laser to cure the isolation layer, which can improve process efficiency and avoid damage to other film layers.

[0066] In some examples, the monomer ratios in the photocurable adhesive are: acrylonitrile 15-35%, butadiene 5-30%, and styrene 40-60%; the solvent for the photocurable adhesive is acetone, with a total acetone content of 85-92%.

[0067] In some optional embodiments, multiple perovskite absorption units 320 are formed in multiple isolation regions, including: filling the isolation region 50 with a perovskite precursor solution using an air knife-assisted coating method, wherein the height of the perovskite precursor solution is less than the height of the isolation line 40; crystallizing the perovskite precursor solution in the isolation region 50 to form multiple perovskite absorption units 320; wherein the thickness of the perovskite absorption unit 320 is less than the height of the isolation line 40.

[0068] In practice, the perovskite absorber layer 32 is formed by crystallization in solution form. Since the first transport layer 31 is hydrophilic, the perovskite precursor solution, after being swept by an air knife, can uniformly fill the bottom of the isolation region 50. Each perovskite absorber unit 320 formed completely fills the surface of the isolation region 50, and the width of the perovskite absorber unit 320 is equal to the width of the isolation region 50.

[0069] The method for fabricating perovskite tandem solar cells provided in this embodiment involves two aspects. First, a perovskite precursor solution is filled into the isolation region 50 using an air knife-assisted coating method. The solution is uniformly filled into the isolation region 50 after being swept by the air knife, thereby improving the high uniformity of the perovskite precursor solution within the multiple isolation regions 50. Second, the perovskite precursor solution within the isolation region 50 is crystallized to form multiple perovskite absorber units 320. This allows for small-area crystallization of the perovskite precursor solution, improving the film quality of the perovskite absorber units 320 and thus increasing the cell efficiency.

[0070] In some alternative embodiments, the perovskite precursor solution includes methylamine lead iodide (MAI), lead bromide (PbBr2), N,N-dimethylformamide (DMF), and dimethyl sulfoxide (DMSO), wherein MAI and PbBr2 are solutes and DMF and DMSO are solvents.

[0071] In some examples, the concentration of MAI is 1.5 M, the concentration of PbBr2 is 1.45 M, the volume ratio of DMF to DMSO is 9:1, and the material of the formed perovskite absorber unit 320 includes MAPbI3.

[0072] In some alternative embodiments, the crystallization process is evaporative crystallization, during which nitrogen gas is used to purge the surface of the perovskite precursor solution. In some optional embodiments, the crystallization temperature is 50°C to 70°C, such as 50°C, 60°C, or 70°C. If the temperature is too high, a large number of grain boundary defects, pinholes, and residual stress are easily generated during the crystallization process, and the perovskite absorber layer 32 will decompose and undergo phase transformation, damaging the material structure. If the temperature is too low, the crystallization rate will be too slow, reducing the efficiency of the process. Therefore, evaporation crystallization at a temperature of 50°C to 70°C can make the solvent evaporation rate moderate, the crystal growth more orderly, the grain size more uniform, and obtain a denser and smoother film, improving the film quality and carrier transport performance of the perovskite absorber layer 32, and also facilitating the subsequent deposition of the second transport layer 33.

[0073] The perovskite tandem solar cell fabrication method provided in this embodiment employs a low-temperature evaporation crystallization process to form multiple perovskite absorber units 320, effectively controlling the crystallization rate and reducing grain boundary defects within the perovskite film. Simultaneously, nitrogen gas is used to purge the surface of the perovskite precursor solution, removing excess solvent during crystallization and improving the growth rate and film quality of the perovskite absorber units 320. Furthermore, by controlling the proportions of the components in the perovskite precursor solution, the quality and speed of perovskite film formation can be improved.

[0074] In some alternative embodiments, the isolation lines 40 are adapted to dissolve in a nonpolar solvent; removal of multiple isolation lines 40 includes: removing the isolation lines 40 with a nonpolar solvent to obtain a plurality of mutually isolated perovskite absorber units 320 arranged in an array; the nonpolar solvent is adapted to dissolve the isolation lines 40; the nonpolar solvent includes n-heptane or toluene.

[0075] In practice, polar solvents cause significant damage to the perovskite absorber layer 32. Using non-polar solvents can remove the isolation line 40 while avoiding damage to the perovskite absorber layer 32.

[0076] The perovskite tandem solar cell fabrication method provided in this embodiment uses a non-polar solvent to remove the isolation line 40, which can dissolve and remove the isolation line 40 while avoiding damage to the perovskite absorber layer 32, thus completing the final shaping of the isolation structure, avoiding lateral transport of charge carriers between the perovskite absorber units 320, and improving the longitudinal transport rate and collection efficiency of charge carriers.

[0077] In some alternative embodiments, the bottom cell 100 is a TOPCon solar cell; the perovskite tandem solar cell is a perovskite-TOPCon tandem cell.

[0078] In some alternative embodiments, a bottom cell 100 is provided, including: providing a silicon wafer 10, the silicon wafer 10 including a front side and a back side disposed opposite to each other; a tunneling oxide layer 11, a doped polysilicon layer 12 and a passivation layer 13 are sequentially formed on the back side of the silicon wafer 10.

[0079] In a specific implementation, the tunneling oxide layer 11 is made of silicon dioxide, and the doping type of the doped polysilicon layer 12 can be the same as that of the silicon wafer 10; the passivation layer 13 includes a first passivation layer 131 and a second passivation layer 132 stacked together, with the first passivation layer 131 relatively close to the doped polysilicon layer 12. The first passivation layer 131 can be made of aluminum oxide, and the second passivation layer 132 can be made of silicon nitride.

[0080] In some alternative embodiments, a charge recombination layer 20 and a first transport layer 31 are sequentially formed on the bottom cell 100, including: forming the charge recombination layer 20 and the first transport layer 31 sequentially on the front side of the silicon wafer 10.

[0081] Optionally, the charge composite layer 20 is made of a transparent conductive oxide and is formed by chemical vapor deposition.

[0082] In some alternative embodiments, both the front and back sides of the silicon wafer 10 are textured, which can significantly enhance the light trapping effect and improve the overall light absorption rate of the cell by utilizing the double-sided textured morphology.

[0083] In some alternative embodiments, the bottom cell 100 is an N-type TOPCon cell; the silicon wafer 10 is an N-type silicon wafer 10; the doped polycrystalline silicon layer 12 is an N-type doped polycrystalline silicon layer; the first transport layer 31 is an electron transport layer; and the second transport layer 33 is a hole transport layer.

[0084] In some alternative embodiments, the bottom cell 100 is a P-type TOPCon cell; the silicon wafer 10 is a P-type silicon wafer 10; the doped polycrystalline silicon layer 12 is a P-type doped polycrystalline silicon layer; the first transport layer 31 is a hole transport layer; and the second transport layer 33 is an electron transport layer.

[0085] The perovskite tandem solar cell fabrication method provided in this embodiment can form different types of perovskite-TOPCon tandem cells according to requirements, improving design flexibility and broadening application scenarios.

[0086] In some alternative embodiments, the electron transport layer is formed using a chemical vapor deposition process. The material of the electron transport layer includes zinc oxide, titanium dioxide, or tin oxide, and the thickness of the electron transport layer is 30 nm to 50 nm, such as 30 nm, 40 nm, or 50 nm.

[0087] The perovskite tandem solar cell fabrication method provided in this embodiment employs chemical vapor deposition to form the electron transport layer, which can improve the film quality and fabrication efficiency of the electron transport layer. Simultaneously, the thickness of the electron transport layer is 30nm~50nm, which can enhance electron extraction efficiency and effectively block hole recombination.

[0088] In some alternative implementations, the hole transport layer is formed by magnetron sputtering or solution spin coating, and the material of the hole transport layer includes nickel oxide; the thickness of the hole transport layer is 10nm~50nm, such as 10nm, 20nm, 30nm, 40nm or 50nm.

[0089] The perovskite tandem solar cell fabrication method provided in this embodiment employs magnetron sputtering or solution spin coating to form the hole transport layer, which can improve the film quality and fabrication efficiency of the hole transport layer. Simultaneously, the hole transport layer thickness is 10nm~50nm, which can enhance hole collection and transport efficiency and effectively block electron recombination.

[0090] In some alternative embodiments, the charge composite layer 20 is formed by chemical vapor deposition. The material of the charge composite layer 20 includes ITO, FTO or AZO, and the thickness of the charge composite layer 20 is 60nm to 80nm, such as 60nm, 65nm, 70nm, 75nm or 80nm.

[0091] The perovskite tandem solar cell fabrication method provided in this embodiment employs a chemical vapor deposition process to form a charge recombination layer 20, which can improve the film quality and fabrication efficiency of the charge recombination layer 20. Simultaneously, the thickness of the charge recombination layer 20 is 60nm~80nm, which can improve the longitudinal conductivity of the charge recombination layer 20 while ensuring high light transmittance.

[0092] In some alternative embodiments, the transparent conductive layer 34 is formed by chemical vapor deposition. The material of the transparent conductive layer 34 includes transparent conductive oxide (TCO), and the thickness of the transparent conductive layer 34 is 60nm to 80nm, such as 60nm, 65nm, 70nm, 75nm or 80nm.

[0093] The perovskite tandem solar cell fabrication method provided in this embodiment optimizes electron extraction and transport efficiency while ensuring high light transmittance by precisely controlling the thickness of each film layer.

[0094] In some alternative embodiments, the second transport layer 33 and the transparent conductive layer 34 cover the entire surface of the perovskite absorber layer 32.

[0095] In some alternative implementations, such as Figure 7AAs shown, the second transport layer 33 fills the bottom of the groove 41, and the second transport layer 33 and the transparent conductive layer 34 completely cover the perovskite absorption layer 32 and the groove 41. Multiple perovskite absorption units 320 are connected in parallel through the entire second transport layer 33 and the first transport layer 31. Since the first transport layer 31 and the second transport layer 33 are respectively disposed on both sides of the perovskite absorption layer 32, the carrier collection efficiency can be improved. In a specific implementation, the second transport layer 33 is formed by a solution spin-coating process, so that the second transport layer 33 can completely fill the groove 41 and completely cover the perovskite absorption layer 32 and the groove 41.

[0096] In some alternative implementations, such as Figure 7B As shown, the second transport layer 33 and the transparent conductive layer 34 fill the bottom of the groove 41, and multiple perovskite absorption units 320 are arranged in parallel. In actual process, the second transport layer 33 and the transparent conductive layer 34 may partially fill the bottom of the groove 41. In this case, the multiple perovskite absorption units 320 are arranged in parallel without affecting their respective performance.

[0097] In some alternative implementations, such as Figure 7C As shown, the second transport layer 33 and the transparent conductive layer 34 fill the sidewalls and bottom of the groove 41, and multiple perovskite absorption units 320 are arranged in parallel. In the actual process, some of the second transport layer 33 and the transparent conductive layer 34 will fill the bottom and sidewalls of the groove 41. The second transport layer 33 completely covers the surface and sidewalls of the perovskite absorption layer 32, which can fully collect the charge carriers in the perovskite absorption unit 320.

[0098] In some optional embodiments, after the second transport layer 33 and the transparent conductive layer 34 are sequentially formed on the surface of the perovskite absorber layer 32 facing away from the first transport layer 31, the fabrication method further includes: forming a first electrode 61 on the side of the transparent conductive layer 34 facing away from the second transport layer 33; and forming a second electrode 62 on the side of the bottom cell 100 facing away from the first transport layer 31.

[0099] The perovskite tandem solar cell fabrication method provided in this embodiment forms a first electrode 61 and a second electrode 62 on both sides of the cell, which can improve the conductive structure and ensure the efficient collection and smooth export of photogenerated carriers.

[0100] In some optional embodiments, after forming the second transport layer 33 and the transparent conductive layer 34, the fabrication method further includes forming a laser isolation groove at the location where each groove is filled using a laser process. The laser isolation groove extends through the second transport layer 33 and the transparent conductive layer 34 between adjacent perovskite absorption units 320. The width of each laser isolation groove is smaller than the width of each groove.

[0101] In practical implementation, laser-isolated grooves are used to separate the second transport layer 33 and the transparent conductive layer 34 corresponding to each perovskite absorber unit 320, so that each perovskite absorber unit 320 forms a sub-cell. Laser-isolated grooves can isolate multiple sub-cells, preventing mutual interference between adjacent sub-cells and improving process design flexibility and cell reliability. Simultaneously, the width of each laser-isolated groove is smaller than the width of each recess, and the sidewalls of each laser-isolated groove retain a portion of the second transport layer 33 and the transparent conductive layer 34, ensuring that the laser-isolated grooves do not expose the sides of the perovskite absorber unit 320, thus avoiding damage to the perovskite absorber unit 320.

[0102] The perovskite tandem solar cell fabrication method provided in this embodiment employs laser technology to create grooves in the second transport layer 33 and the transparent conductive layer 34 located between adjacent perovskite absorber units 320. The width of the laser-isolated groove is smaller than the width of the recess, thus avoiding damage to the perovskite absorber unit 320 and the perovskite absorber layer 32. Compared to related technologies that directly laser-groove the entire perovskite absorber layer, this embodiment effectively avoids damage to the perovskite absorber unit 320. Furthermore, by controlling the width of the laser-isolated groove to be relatively small, a larger area of ​​the second transport layer 33 can be ensured, improving the collection efficiency of charge carriers in each perovskite absorber unit 320, thereby increasing the cell efficiency.

[0103] In some embodiments, the laser isolation groove formed at the corresponding position of the groove 41 penetrates the second transmission layer 33 and the transparent conductive layer 34, and exposes the surface of the first transmission layer 31. In other embodiments, the laser isolation groove formed at the corresponding position of the groove 41 may also extend into the first transmission layer 31 or into the charge recombination layer 20.

[0104] In practice, the depth of the laser isolation groove can be set according to requirements, and this disclosure does not limit it.

[0105] This disclosure also provides a schematic flowchart of another method for fabricating perovskite tandem solar cells, including but not limited to steps S201 to S209.

[0106] Step S201, provide a bottom battery 100, such as Figure 2 As shown.

[0107] In a specific implementation, the bottom cell 100 is a TOPCon cell. The bottom cell 100 is formed by: providing a silicon wafer 10, which includes a front side and a back side disposed opposite to each other; and sequentially forming a tunneling oxide layer 11, a doped polysilicon layer 12, and a passivation layer 13 on the back side of the silicon wafer 10. In some examples, the silicon wafer 10 is an N-type silicon wafer, and the doped polysilicon layer 12 is an N-type doped polysilicon layer. The tunneling oxide layer 11 is made of silicon dioxide, and the passivation layer 13 includes a first passivation layer 131 and a second passivation layer 132 stacked together, with the first passivation layer 131 relatively close to the N-type doped polysilicon layer.

[0108] Step S202: A charge composite layer 20 is formed on the bottom cell 100 using a chemical vapor deposition process, such as... Figure 3 As shown.

[0109] In a specific implementation, a charge recombination layer 20 is formed on the front side of the silicon wafer 10. The material of the charge recombination layer 20 includes ITO, and the thickness of the charge recombination layer 20 is 60nm~80nm.

[0110] Step S203: A first transport layer 31 is formed on the surface of the charge recombination layer 20 facing away from the bottom battery 100, such as... Figure 3 As shown.

[0111] In specific implementations, the first transport layer 31 covers the entire surface of the charge composite layer 20. In some examples, the first transport layer 31 is an electron transport layer, which is formed using a chemical vapor deposition process. The material of the electron transport layer includes zinc oxide, and the thickness of the electron transport layer is 30 nm to 50 nm.

[0112] In step S204, multiple isolation lines 40 are formed on the surface of the first transport layer 31 on the side opposite to the charge recombination layer 20. These isolation lines 40 extend and connect along a first direction and a second direction, forming a mesh structure. The isolation lines 40 isolate the surface of the first transport layer 31 into several arrayed isolation regions 50, such as... Figure 4A and Figure 4B As shown.

[0113] In specific implementation, the first direction and the second direction intersect. Among the multiple isolation lines 40, some isolation lines 40 extend along the first direction, and others extend along the second direction. The multiple isolation lines 40 are interconnected to form a grid-like structure. At the same time, the area between the multiple isolation lines 40 is an isolation region 50. The multiple isolation lines 40 divide the surface of the first transmission layer 31 into several arrayed isolation regions 50.

[0114] Step S205: A perovskite precursor solution is filled into the isolation area 50 using an air knife-assisted coating method. The height of the perovskite precursor solution is less than the height of the isolation line 40.

[0115] In practice, the perovskite precursor solution is uniformly sprayed within each isolation zone of 50 mm, while simultaneously being evenly dispersed using an air knife. In some examples, the air knife moving speed is 5–10 mm / s, and the nitrogen pressure is 0.2 MPa.

[0116] Step S206 involves crystallizing the perovskite precursor solution within the isolation region 50 to form multiple perovskite absorption units 320 within the multiple isolation regions 50. These multiple perovskite absorption units 320 are arranged in an array to form a perovskite absorption layer 32. The thickness of the perovskite absorption unit 320 is less than the height of the isolation line 40. Figure 5A and Figure 5B As shown.

[0117] In practice, the crystallization process is low-temperature evaporation crystallization at a temperature of 60°C. Simultaneously, nitrogen gas is used to purge the surface of the perovskite precursor solution at a pressure of 0.2 MPa. Each formed perovskite absorber unit 320 completely fills the surface of the isolation region 50, and the width of the perovskite absorber unit 320 is equal to the width of the isolation region 50.

[0118] Step S207: A non-polar solvent is used to remove the isolation lines 40 to obtain several mutually isolated perovskite absorber units 320 arranged in an array, and a mesh-like groove 41 is formed between adjacent perovskite absorber units 320, such as... Figure 6 As shown.

[0119] In practice, non-polar solvents are suitable for dissolving the isolation lines 40, which can remove the isolation lines 40 without damaging the perovskite absorber layer 32. In some examples, n-heptane is used to clean the isolation lines 40, forming multiple grooves 41 at the location of the isolation lines 40, so that multiple perovskite absorber units 320 are isolated from each other, and each groove 41 exposes the surface of the first transport layer 31 between adjacent perovskite absorber units 320.

[0120] In step S208, a second transport layer 33 and a transparent conductive layer 34 are sequentially formed on the surface of the perovskite absorber layer 32 facing away from the first transport layer 31, as shown below. Figure 7A , Figure 7B or Figure 7C As shown.

[0121] In specific implementation, the second transport layer 33 is a hole transport layer, formed using magnetron sputtering or solution spin coating. The hole transport layer is made of nickel oxide and has a thickness of 10 nm to 50 nm. A transparent conductive layer 34 is formed using chemical vapor deposition. The transparent conductive layer 34 can be made of TCO and has a thickness of 60 nm to 80 nm.

[0122] In Example 1, such as Figure 7AAs shown, the hole transport layer (i.e., the second transport layer 33) fills the groove 41 and covers the surface of the perovskite absorption unit 320. The transparent conductive layer 34 completely covers the perovskite absorption layer 32 and the hole transport layer surface above the groove 41. Multiple perovskite absorption units 320 are connected in parallel through the entire surface of the electron transport layer and hole transport layer. Specifically, the hole transport layer (i.e., the second transport layer 33) is formed by a solution spin coating process, so that the hole transport layer can completely fill the groove 41 and completely cover the perovskite absorption layer 32 and the surface above the groove 41. In the solution spin coating process, the precursor is nickel nitrate + ethanolamine (molar ratio approximately 1:1); the solvent is 2-methoxyethanol. First, a film is formed by spin coating at a speed of 3000~5000 rpm for 30 seconds. Then, nickel oxide is formed as the hole transport layer by annealing at a temperature of 300~450℃ for 30~60 minutes.

[0123] In Example 2, such as Figure 7B As shown, the hole transport layer and the transparent conductive layer 34 fill the bottom of the groove 41, and multiple perovskite absorption units 320 are arranged in parallel. Specifically, the hole transport layer (i.e., the second transport layer 33) is formed by magnetron sputtering. The power in the magnetron sputtering process is 50~150 W, and the gas pressure is 0.5~3 Pa (Ar / O2 mixed atmosphere).

[0124] In Example 3, such as Figure 7C As shown, the hole transport layer and the transparent conductive layer 34 fill the sidewalls and bottom of the groove 41, and multiple perovskite absorption units 320 are arranged in parallel. Specifically, the hole transport layer (i.e., the second transport layer 33) is formed using a magnetron sputtering process.

[0125] In step S209, a first electrode 61 is formed on the side of the transparent conductive layer 34 facing away from the second transport layer 33; and a second electrode 62 is formed on the side of the bottom battery 100 facing away from the first transport layer 31.

[0126] In a specific implementation, the first electrode 61 and the second electrode 62 are formed by a printing process. Optionally, the first electrode 61 is located above the corresponding position of the perovskite absorption unit 320.

[0127] In the description of this specification, the references to terms such as "this embodiment," "an embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this disclosure. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Furthermore, those skilled in the art can combine and integrate the different embodiments or examples described in this specification and the features of different embodiments or examples without contradiction. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this disclosure, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0128] The above description does not provide detailed explanations of the technical aspects of each layer's patterning, etching, etc. However, those skilled in the art should understand that various technical means can be used to form layers and regions of the desired shape. Furthermore, to form the same structure, those skilled in the art can also design methods that are not entirely identical to those described above. Additionally, although various embodiments have been described above, this does not mean that the measures in the various embodiments cannot be used advantageously in combination.

[0129] The above description is merely a preferred embodiment and the technical principles employed in this disclosure. Those skilled in the art will understand that this disclosure is not limited to the specific embodiments described above, and various obvious changes, readjustments, combinations, and substitutions can be made without departing from the scope of protection of this disclosure. Therefore, although this disclosure has been described in detail through the above embodiments, it is not limited to the above embodiments. Many other equivalent embodiments may be included without departing from the concept of this disclosure, and the scope of protection of this disclosure is determined by the scope of the appended claims.

Claims

1. A method for fabricating a perovskite tandem solar cell, characterized in that, include: A bottom battery is provided, on which a charge recombination layer and a first transport layer are sequentially formed; Multiple isolation lines are formed on the surface of the first transport layer on the side opposite to the charge recombination layer. The multiple isolation lines extend and connect along the first direction and the second direction to form a grid structure. The isolation lines isolate the surface of the first transport layer into several arrayed isolation regions. Multiple perovskite absorption units are formed in multiple isolation regions, and the array of multiple perovskite absorption units forms a perovskite absorption layer. Remove the multiple isolation lines to form a grid-like groove between adjacent perovskite absorber units; A second transport layer and a transparent conductive layer are sequentially formed on the surface of the perovskite absorber layer opposite to the first transport layer.

2. The method for preparing a perovskite tandem solar cell according to claim 1, characterized in that, Multiple isolation lines are formed on the surface of the first transport layer on the side opposite to the charge recombination layer, including: A patterned isolation adhesive layer is formed on the surface of the first transport layer facing away from the charge composite layer using a printing process. The pattern of the isolation adhesive layer is a grid structure. The insulating adhesive layer is cured to obtain multiple insulating lines.

3. The method for preparing a perovskite tandem solar cell according to claim 1, characterized in that, Multiple isolation lines are formed on the surface of the first transport layer on the side opposite to the charge recombination layer, including: An insulating adhesive layer is formed on the surface of the first transport layer on the side opposite to the charge recombination layer. The release adhesive layer is selectively cured to form multiple grid-like release lines in the cured area; multiple uncured areas are separated between the multiple release lines. Remove the release adhesive layer from the uncured areas, and multiple isolation lines isolate the surface of the first transmission layer into several arrayed isolation areas, which expose the surface of the first transmission layer.

4. The method for preparing a perovskite tandem solar cell according to claim 2 or 3, characterized in that, The material of the release adhesive layer is a photocurable adhesive; the release adhesive layer is suitable for laser curing. The photocurable adhesive includes acrylonitrile-butadiene-styrene resin.

5. The method for preparing a perovskite tandem solar cell according to claim 1, characterized in that, The formation of multiple perovskite absorber units within the multiple isolation regions includes: A perovskite precursor solution is filled into the isolation area using an air knife-assisted coating method, wherein the height of the perovskite precursor solution is less than the height of the isolation line. The perovskite precursor solution within the isolation area is crystallized to form multiple perovskite absorption units; the thickness of the perovskite absorption unit is less than the height of the isolation line.

6. The method for preparing a perovskite tandem solar cell according to claim 5, characterized in that, The crystallization process is evaporative crystallization, and nitrogen gas is used to purge the surface of the perovskite precursor solution during the crystallization process; the temperature of the crystallization process is 50℃~70℃; The perovskite precursor solution comprises methylamine lead iodine, lead bromide, N,N-dimethylformamide, and dimethyl sulfoxide, wherein methylamine lead iodine and lead bromide are solutes, and N,N-dimethylformamide and dimethyl sulfoxide are solvents.

7. The method for preparing a perovskite tandem solar cell according to claim 1, characterized in that, The isolation line is suitable for dissolving in nonpolar solvents; The removal of the multiple isolation lines includes: removing the isolation lines using a non-polar solvent to obtain a plurality of mutually isolated perovskite absorber units arranged in an array; the non-polar solvent is suitable for dissolving the isolation lines; the non-polar solvent includes n-heptane or toluene.

8. The method for preparing a perovskite tandem solar cell according to claim 1, characterized in that, The bottom cell is a tunnel oxide passivated contact solar cell; The provided base battery includes: A silicon wafer is provided, the silicon wafer including a front side and a back side disposed opposite to each other; A tunneling oxide layer, a doped polysilicon layer, and a passivation layer are sequentially formed on the back side of the silicon wafer; The step of sequentially forming a charge recombination layer and a first transport layer on the bottom cell includes: sequentially forming a charge recombination layer and a first transport layer on the front side of the silicon wafer.

9. The method for preparing a perovskite tandem solar cell according to claim 8, characterized in that, The silicon wafer is an N-type silicon wafer, the doped polycrystalline silicon layer is an N-type doped polycrystalline silicon layer, the first transport layer is an electron transport layer, and the second transport layer is a hole transport layer; Alternatively, the silicon wafer is a P-type silicon wafer, and the doped polycrystalline silicon layer is a P-type doped polycrystalline silicon layer; the first transport layer is a hole transport layer, and the second transport layer is an electron transport layer; The electron transport layer is formed using a chemical vapor deposition process, and the material of the electron transport layer includes zinc oxide; the hole transport layer is formed using a magnetron sputtering process or a solution spin coating process, and the material of the hole transport layer includes nickel oxide.

10. The method for preparing a perovskite tandem solar cell according to claim 1, characterized in that, After the second transport layer and the transparent conductive layer are sequentially formed on the surface of the perovskite absorber layer opposite to the first transport layer, the preparation method further includes: A first electrode is formed on the side of the transparent conductive layer opposite to the second transport layer; A second electrode is formed on the side of the bottom battery opposite to the first transport layer.

11. A perovskite tandem solar cell, characterized in that, It is prepared by the method of any one of claims 1 to 10 for the fabrication of perovskite tandem solar cells.

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