Preparation method of perovskite laminated solar cell

Abstract

The invention provides a preparation method of a perovskite laminated solar cell and the perovskite laminated solar cell, and the method comprises the steps: firstly, placing a silicon wafer in an alkaline solution to obtain a double-sided textured silicon wafer, and then preparing multiple layers of thin films on a first surface and a second surface of the double-sided textured silicon wafer, comprising an intrinsic amorphous silicon thin film layer, a doped silicon thin film layer, a composite layer, a hole transport layer and the like, and then preparing a perovskite light absorption layer by adopting a solution spin-coating method, and sequentially preparing a passivation layer, an electron transport layer and a protection layer. And finally, preparing a transparent conductive oxide film layer and a copper electrode by adopting physical vapor deposition and electroplating treatment, preparing an anti-reflection layer on the first transparent conductive oxide film layer at the same time, and finally obtaining the perovskite laminated solar cell. Compared with an atomic layer deposition technology, the edge covering protection treatment method adopted in the electroplating process can save the equipment cost, does not need to worry about the productivity problem, and is suitable for large-scale industrialization.

Description

Technical Field

[0001] The present application relates to the technical field of solar cells, and more particularly, to a method for preparing a perovskite tandem solar cell and a perovskite tandem solar cell. Background Art

[0002] The dual-terminal perovskite / silicon tandem solar cell under research aims to break through the efficiency limit of single-junction crystalline silicon cells without adding too much cost and achieve a high-efficiency perovskite / crystalline silicon tandem solar cell. So far, only a few commercially sized perovskite / crystalline silicon tandem solar cells have been reported, and most of their metallization processes use evaporated nano silver metal particles or screen-printed ultra-low temperature silver paste. From the perspective of commercialization cost, since the material costs of low-temperature silver paste and nano silver metal particles are too high, it is not very suitable for large-scale production.

[0003] Currently, copper electroplating in perovskite solar cells uses atomic layer deposition technology. Atomic layer deposition equipment is expensive and the equipment cost is high. At the same time, although the thin film prepared by atomic layer deposition technology is dense and pore-free, it also means low production capacity and too long process time, making it difficult to meet the production capacity requirements. In addition, depositing a layer of metal oxide on perovskite will seriously affect the light absorption of the battery, increase additional absorption loss, resulting in a decrease in current density. At the same time, some metal oxides have poor conductivity, which will also reduce the lateral conductivity of the entire battery and lower the electrical performance of the battery. Summary of the Invention

[0004] The present application aims to at least solve one of the technical problems existing in the prior art or related technologies.

[0005] To this end, in the first aspect of the present application, a method for preparing a perovskite tandem solar cell is proposed.

[0006] In the second aspect of the present application, a perovskite tandem solar cell is proposed.

[0007] In view of this, according to the first aspect of the present application, there is provided a method for preparing a perovskite tandem solar cell, the method comprising:

[0008] Placing a silicon wafer in an alkaline solution to obtain a double-sided textured silicon wafer, and cleaning the double-sided textured silicon wafer;

[0009] On a first surface of the double-sided textured silicon wafer, sequentially preparing a first intrinsic amorphous silicon thin film layer, a first doped silicon thin film layer, a composite layer, and a hole transport layer;

[0010] On a second surface of the double-sided textured silicon wafer opposite to the first surface, sequentially preparing a second intrinsic amorphous silicon thin film layer and a second doped silicon thin film layer;

[0011] The perovskite light-absorbing layer is prepared on the hole transport layer by solution spin coating method, and a passivation layer, an electron transport layer and a protective layer are sequentially prepared on the perovskite light-absorbing layer;

[0012] The first transparent conductive oxide thin film layer is deposited on the protective layer by physical vapor deposition method, and the second transparent conductive oxide thin film layer is deposited on the second doped silicon thin film layer;

[0013] The first copper electrode is prepared on the first transparent conductive oxide thin film layer by edge protection treatment method and electroplating treatment method, and the second copper electrode is prepared on the second transparent conductive oxide thin film layer. The edge protection treatment method is to protect the perovskite light-absorbing layer when preparing the first copper electrode and the second copper electrode;

[0014] An antireflection layer is prepared in the area other than the first copper electrode on the first transparent conductive oxide thin film layer to obtain a perovskite tandem solar cell.

[0015] In a possible technical solution, further, the perovskite light-absorbing layer can be any one of the first perovskite light-absorbing layer and the second perovskite light-absorbing layer.

[0016] In a possible technical solution, further, the first perovskite light-absorbing layer is prepared on the hole transport layer by solution spin coating method, specifically:

[0017] Formamidinium iodide, formamidinium bromide, and formamidinium chloride are dissolved in isopropyl alcohol solution in a ratio of 3:1:2 to obtain a first organic amine solution;

[0018] Lead iodide and cesium bromide are simultaneously evaporated and covered on the surface of the hole transport layer by a thermal evaporation device to form an inorganic layer on the surface of the hole transport layer;

[0019] The double-sided textured silicon wafer with the prepared inorganic layer is placed in a nitrogen protection box, and the first organic amine solution is evenly dropped on the inorganic layer, and the rotation speed and rotation time are set to rotate the double-sided textured silicon wafer;

[0020] The double-sided textured silicon wafer is taken out of the nitrogen protection box and subjected to annealing heat treatment to obtain the double-sided textured silicon wafer with the prepared first perovskite light-absorbing layer.

[0021] In a possible technical solution, further, the second perovskite light-absorbing layer is prepared on the hole transport layer by solution spin coating method, specifically:

[0022] Formamidinium iodide, formamidinium bromide, formamidinium chloride, lead iodide and cesium bromide are dissolved in ethanol solution in a ratio of 3:1:1:5:2 to obtain a second organic amine solution;

[0023] Place the double-textured silicon wafer with the prepared hole transport layer into a nitrogen protection box, evenly drip the second organic amine solution onto the inorganic layer, and set the rotation speed and rotation time to rotate the double-textured silicon wafer.

[0024] Take out the double-textured silicon wafer from the nitrogen protection box and perform annealing heat treatment to obtain the double-textured silicon wafer with the prepared second perovskite light-absorbing layer.

[0025] In a possible technical solution, further, a passivation layer, an electron transport layer, and a protective layer are sequentially prepared on the perovskite light-absorbing layer; specifically,

[0026] Place the double-textured silicon wafer with the prepared perovskite light-absorbing layer into a mask plate and deposit a layer of lithium fluoride to obtain the passivation layer;

[0027] Deposit a layer of C60 on the passivation layer to obtain the electron transport layer;

[0028] Place the double-textured silicon wafer with the prepared electron transport layer into an atomic layer deposition device, and obtain the protective layer through the alternating purge of tin source and water source.

[0029] In a possible technical solution, further, a first copper electrode is prepared on the first transparent conductive oxide thin film layer and a second copper electrode is prepared on the second transparent conductive oxide thin film layer by using an edge protection treatment method and an electroplating treatment method; specifically:

[0030] Deposit a first seed layer on the first transparent conductive oxide thin film layer and a second seed layer on the second transparent conductive oxide thin film layer by physical vapor deposition;

[0031] Print a first mask layer on the first seed layer and a second mask layer on the second seed layer by printing method;

[0032] Use photosensitive ink to perform the first edge protection on the sides of the double-textured silicon wafer printed with the first mask layer and the second mask layer;

[0033] Expose and develop the double-textured silicon wafer after the edge protection to obtain a first grid line trench on the first mask layer and a second grid line trench on the second mask layer;

[0034] Electroplate the first copper electrode on the first grid line trench and electroplate the second copper electrode in the second grid line trench by electroplating method;

[0035] Place the double-textured silicon wafer with the prepared first copper electrode and second copper electrode into an alkaline solution to remove the first mask layer and the second mask layer. Meanwhile, the photosensitive ink for the first edge protection will also be removed;

[0036] Use photosensitive ink to perform second edge protection on the side edges of the double-textured silicon wafer after removing the first mask layer and the second mask layer, and form an edge layer on the side edges of the double-textured silicon wafer;

[0037] Place the double-textured silicon wafer after the second edge protection into an acidic solution to remove the first seed layer and the second seed.

[0038] In a possible technical solution, further, the first doped silicon thin film layer is a phosphorus-doped silicon thin film layer; the second doped silicon thin film layer is a boron-doped silicon thin film layer.

[0039] In a possible technical solution, further, the first transparent conductive oxide thin film layer and the second transparent conductive oxide thin film layer can be one of indium tin oxide thin film, tungsten-doped indium oxide thin film, doped tin oxide thin film, and doped aluminum oxide thin film.

[0040] In a possible technical solution, further, the hole transport layer is a nickel oxide layer.

[0041] According to the second aspect of the present application, a perovskite tandem solar cell is provided, which is prepared by the preparation method of a perovskite tandem solar cell according to any one of the first aspect.

[0042] According to the preparation method of a perovskite tandem solar cell of the first aspect of the present application, the beneficial effects are as follows:

[0043] Through double-sided texturing treatment, a textured surface structure is formed on the silicon wafer surface, increasing the diffuse reflection of light, enabling more solar energy to be captured by the silicon wafer, thereby improving the light absorption efficiency of the solar cell; multilayer thin film structures are prepared on both sides of the silicon wafer, including an intrinsic amorphous silicon thin film layer, a doped silicon thin film layer, a composite layer, a hole transport layer, etc.; these thin film layers contribute to the effective separation and transport of charges, reducing charge recombination losses, thereby improving the conversion efficiency of the solar cell; a perovskite light-absorbing layer is prepared by the solution spin-coating method, which can precisely control the thickness and uniformity of the perovskite layer, thereby improving the light absorption efficiency and charge collection efficiency; meanwhile, the introduction of a passivation layer can further reduce charge recombination at the interface, improving the performance of the solar cell; a transparent conductive oxide thin film layer is prepared by physical vapor deposition, and the thin film prepared by this method has good electrical conductivity and light transmittance, which is beneficial to the collection and transport of charges; meanwhile, the transparent conductive thin film layer can also protect the underlying thin film structure, improving the stability of the solar cell; a copper electrode is prepared by the edge protection treatment method and the electroplating treatment method, which can protect the perovskite light-absorbing layer from damage while preparing the electrode, avoiding the influence on the performance of the solar cell during the electrode preparation process; compared with atomic layer deposition technology, the edge protection treatment method can not only save equipment costs, but also does not need to worry about production capacity issues, and is suitable for large-scale industrialization; an antireflection layer is prepared on the first transparent conductive oxide thin film layer, which can reduce the reflection of light, enabling more sunlight to enter the interior of the solar cell and be absorbed, thereby improving the light utilization rate and the conversion efficiency of the solar cell.

[0044] Additional aspects and advantages of the present application will become apparent in the following description section or be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] The above and / or additional aspects and advantages of the present application will become apparent and be readily understood from the description of the embodiments in conjunction with the following drawings, wherein:

[0046] Figure 1 A flowchart showing a preparation method of a perovskite tandem solar cell according to an embodiment of the present application is shown;

[0047] Figure 2 A schematic structural diagram showing a perovskite tandem solar cell including a first perovskite light-absorbing layer according to an embodiment of the present application is shown;

[0048] Figure 3 A schematic structural diagram showing a perovskite tandem solar cell including a second perovskite light-absorbing layer according to an embodiment of the present application is shown.

[0049] Wherein, Figures 2 to 3 The corresponding relationship between the reference numerals in the drawings and the component names is as follows:

[0050] 100. Double-sided textured silicon wafer;

[0051] 210. First intrinsic amorphous silicon thin film layer; 310. First doped silicon thin film layer; 410. Composite layer; 510. Hole transport layer; 611. First perovskite light-absorbing layer; 612. Second perovskite light-absorbing layer; 710. Passivation layer; 810. Electron transport layer; 910. Protective layer; 1010. First transparent conductive oxide thin film layer; 1110. First copper electrode; 1210. Anti-reflection layer;

[0052] 220. Second intrinsic amorphous silicon thin film layer; 320. Second doped silicon thin film layer; 1020. Second transparent conductive oxide thin film layer; 1120. Second copper electrode;

[0053] 1300. Edge wrapping layer. Detailed implementation manners

[0054] In order to more clearly understand the above objects, features and advantages of the present application, the present application will be further described in detail below with reference to the accompanying drawings and specific implementation manners. It should be noted that, without conflict, the embodiments of the present application and the features in the embodiments may be combined with each other.

[0055] In the following description, many specific details are set forth in order to fully understand the present application. However, the present application may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present application is not limited by the specific embodiments disclosed below.

[0056] Next, refer to Figures 1 to 2 Describe a method for preparing a perovskite tandem solar cell and a perovskite tandem solar cell according to some embodiments of the present application.

[0057] Example 1

[0058] A method for preparing a perovskite tandem solar cell includes the following steps:

[0059] S100: Place the silicon wafer in an alkaline solution to obtain a double-sided textured silicon wafer 100, and clean the double-sided textured silicon wafer 100;

[0060] Specifically, place the silicon wafer in a mixed solution of potassium hydroxide or sodium hydroxide, a special additive for small surface texture, and ultrapure water for reaction for 200 s - 1800 s to form a double-sided textured silicon wafer 100 with a pyramid structure on the surface, and the size of the pyramid is 0.5 um - 4 um; then wash away the residual mixed solution in the double-sided textured silicon wafer 100 with clean water.

[0061] S200: On the first side of the double-sided textured silicon wafer 100, sequentially prepare a first intrinsic amorphous silicon thin film layer 210, a first doped silicon thin film layer 310, a composite layer 410, and a hole transport layer 510;

[0062] Specifically, the first doped silicon thin film layer 310 is a phosphorus-doped silicon thin film layer, the thickness of the first doped silicon thin film layer 310 is 5 nm - 40 nm, the composite layer 410 is an indium tin oxide layer, the thickness of the composite layer 410 is 20 nm, the hole transport layer 510 is a nickel oxide layer, and the thickness of the hole transport layer 510 is 12 nm.

[0063] S300: On the second side of the double-sided textured silicon wafer 100 opposite to the first side, sequentially prepare a second intrinsic amorphous silicon thin film layer 220 and a second doped silicon thin film layer 320;

[0064] Specifically, the second doped silicon thin film layer 320 is a boron-doped silicon thin film layer, and the thickness of the second doped silicon thin film layer 320 is 5 nm - 60 nm.

[0065] S400: Prepare a perovskite light-absorbing layer on the hole transport layer 510 by solution spin coating method, and sequentially prepare a passivation layer 710, an electron transport layer 810, and a protective layer 910 on the perovskite light-absorbing layer;

[0066] Furthermore, the perovskite light-absorbing layer can be any one of a first perovskite light-absorbing layer 611 and a second perovskite light-absorbing layer 612;

[0067] It should be noted that during the process of preparing the perovskite tandem solar cell, the first perovskite light-absorbing layer 611 or the second perovskite light-absorbing layer 612 can be selected according to specific requirements or performance optimization goals.

[0068] Optionally, in S400, the first perovskite light-absorbing layer 611 is prepared on the hole transport layer 510 by solution spin coating method, specifically:

[0069] S411: Dissolve formamidinium iodide, formamidinium bromide, and formamidinium chloride in an isopropanol solution in a ratio of 3:1:2 to obtain a first organic amine solution;

[0070] S412: Simultaneously evaporate and cover lead iodide and cesium bromide on the surface of the hole transport layer 510 through a thermal evaporation device to form an inorganic layer on the surface of the hole transport layer 510;

[0071] S413: Place the double-sided textured silicon wafer 100 with the prepared inorganic layer into a nitrogen protection box, uniformly drop the first organic amine solution on the inorganic layer, and set the rotation speed and rotation time to rotate the double-sided textured silicon wafer 100;

[0072] S414: Take out the double-sided textured silicon wafer 100 from the nitrogen protection box, perform annealing heat treatment, and obtain the double-sided textured silicon wafer 100 with the first perovskite light-absorbing layer 611 prepared.

[0073] It should be noted that in S411, an electronic balance is used to weigh formamidinium iodide (FAI), formamidinium bromide (FABr), and formamidinium chloride (FACl) and dissolve them in an isopropyl alcohol solution in a ratio of 3:1:2 to obtain a first organic amine solution with a concentration of 0.65 M. This is a pure formamidinium organic amine salt system. In S412, a thermal evaporation device is used, and the left and right evaporation sources simultaneously evaporate lead iodide and cesium bromide to form an inorganic layer. The evaporation rate of lead iodide needs to be stable at 1.2 Å / s, and the evaporation rate of cesium bromide needs to be stable at 0.12 Å / s. S413: Place the double-sided textured silicon wafer 100 with the prepared inorganic layer into the nitrogen protection box, use a pipette to take 500 μL of the first organic amine solution and evenly drop it on the surface of the inorganic layer. After standing for 30 seconds, rotate it at a speed of 4500 revolutions per minute for 30 seconds, and then take it out of the nitrogen protection box and heat-anneal it at 150 °C for 25 minutes in an environment with a humidity of 40% to obtain the double-sided textured silicon wafer 100 with the first perovskite light-absorbing layer 611 prepared.

[0074] It should be noted that in S411, by precisely controlling the ratio of formamidinium iodide, formamidinium bromide, and formamidinium chloride (3:1:2), the chemical composition of the perovskite light-absorbing layer can be precisely regulated, thereby optimizing its optoelectronic properties. This precise composition control is crucial for improving the conversion efficiency of solar cells. In S412, a layer of inorganic layer (composed of lead iodide and cesium bromide) is formed on the surface of the hole transport layer 510 through a thermal evaporation device. This inorganic layer can serve as a buffer layer between the perovskite light-absorbing layer and the hole transport layer 510, optimize the interfacial contact between the two, reduce charge recombination losses, and improve charge transport efficiency. In S413, in the nitrogen protection box, the first organic amine solution is evenly dropped on the inorganic layer, and the double-sided textured silicon wafer 100 is rotated by setting the rotation speed and rotation time. This method can ensure the uniform distribution of the perovskite solution on the silicon wafer surface, thereby preparing a perovskite light-absorbing layer with good uniformity. This is very important for improving the performance stability and consistency of solar cells. The annealing heat treatment in S414 can promote the crystallization of the perovskite light-absorbing layer, improve its crystallization quality and stability. Good crystallization quality helps to reduce defects and charge recombination centers, thereby improving the conversion efficiency and long-term stability of solar cells. Throughout S400, especially in S413, a nitrogen protection box is used for preparation. As an inert gas, nitrogen can exclude the influence of impurities such as oxygen and moisture in the air on the preparation process of the perovskite light-absorbing layer, thereby ensuring the preparation of a high-quality perovskite light-absorbing layer.

[0075] Optionally, in S400, a solution spin coating method is used to prepare the second perovskite light-absorbing layer 612 on the hole transport layer 510. Specifically:

[0076] S421: Dissolve formamidinium iodide, formamidinium bromide, formamidinium chloride, lead iodide, and cesium bromide in an ethanol solution in a ratio of 3:1:1:5:2 to obtain a second organic amine solution;

[0077] S422: Place the double-sided textured silicon wafer 100 with the prepared hole transport layer 510 into a nitrogen protection box, evenly drop the second organic amine solution on the inorganic layer, and set the rotation speed and rotation time to rotate the double-sided textured silicon wafer 100;

[0078] S423: Take out the double-sided textured silicon wafer 100 from the nitrogen protection box, perform annealing heat treatment to obtain the double-sided textured silicon wafer 100 with the prepared second perovskite light-absorbing layer 612.

[0079] It should be noted that in S421, an electronic balance is used to weigh formamidinium iodide (FAI), formamidinium bromide (FABr), formamidinium chloride (FACl), lead iodide (PbI2), cesium bromide (CsBr), and dissolve them in an ethanol solution in a ratio of 3:1:1:5:2 to obtain a second organic amine solution with a concentration of 0.70M, which is the perovskite precursor solution; in S422, the double-sided textured silicon wafer 100 with the prepared hole transport layer 510 is placed into a nitrogen protection box, and 600 μL of the second organic amine solution is taken with a pipette and evenly dropped on the surface of the hole transport layer 510. After standing for 15 seconds, it is rotated at a speed of 4000 revolutions per minute for 30 seconds, and then taken out from the nitrogen protection box and heated and annealed at 150 °C for 25 minutes in an environment with a humidity of 40% to obtain the double-sided textured silicon wafer 100 with the prepared second perovskite light-absorbing layer 612.

[0080] It should be noted that in S421, a perovskite precursor solution with multiple components can be prepared by dissolving formamidinium iodide, formamidinium bromide, formamidinium chloride, lead iodide, and cesium bromide in an ethanol solution in a specific ratio (3:1:1:5:2); compared with the S410 series of steps, the S420 series of steps omits the separate inorganic layer preparation step (such as S412); instead, it is achieved by directly adding inorganic components (lead iodide and cesium bromide) to the organic amine solution; this simplified preparation step can reduce the process complexity, improve production efficiency, and may reduce production costs, but the uniform coverage of the second perovskite light-absorbing layer 612 is not as good as that of the first perovskite light-absorbing layer 611; in S422, the second organic amine solution is uniformly dropped onto the hole transport layer 510 in a nitrogen protection box, and the solution is ensured to be evenly distributed by rotating the double-sided textured silicon wafer 100; in S423, the double-sided textured silicon wafer 100 is taken out of the nitrogen protection box and subjected to annealing heat treatment; the annealing treatment can promote the crystallization of the perovskite light-absorbing layer, improve its crystallization quality and stability; good crystallization quality helps to reduce defects and charge recombination centers, thereby improving the conversion efficiency and long-term stability of the solar cell.

[0081] Furthermore, in S400, a passivation layer 710, an electron transport layer 810, and a protective layer 910 are sequentially prepared on the perovskite light-absorbing layer; specifically,

[0082] S431: The double-sided textured silicon wafer 100 with the prepared perovskite light-absorbing layer is placed in a mask plate to deposit a layer of lithium fluoride to obtain the passivation layer 710;

[0083] S432: A layer of C60 is deposited on the passivation layer 710 to obtain the electron transport layer 810;

[0084] S433: The double-sided textured silicon wafer 100 with the prepared electron transport layer 810 is placed in an atomic layer deposition device, and by alternately purging with a tin source and a water source, the protective layer 910 is obtained.

[0085] It should be noted that first, in S431, the double-sided textured silicon wafer 100 with the prepared perovskite light-absorbing layer is placed in a specific mask plate, and a layer of lithium fluoride (LiF) with a thickness of 1 nm is deposited at a deposition rate of 0.12 Å / s as the passivation layer 710; then, in S432, a layer of C60 with a thickness of 20 nm is deposited on the passivation layer 710 at a deposition rate of 0.15 Å / s as the electron transport layer 810; finally, in S433, the double-sided textured silicon wafer 100 with the prepared electron transport layer 810 is placed in an atomic layer deposition device (ALD), and by alternately purging with a tin source and a water source, a layer-by-layer tin dioxide (SnO2) molecular layer is formed by reaction, and finally, through 120 alternating purge cycles, a protective layer 910 with a thickness of 15 nm is obtained.

[0086] It should be noted that in step S431, a layer of lithium fluoride is deposited on the perovskite light-absorbing layer as the passivation layer 710; lithium fluoride has excellent passivation effect, which can effectively reduce the density of defect states on the surface of the perovskite light-absorbing layer, thereby reducing the charge recombination rate and improving the charge collection efficiency; in addition, lithium fluoride can also provide good interfacial contact, which helps the transfer of electrons from the perovskite light-absorbing layer to the electron transport layer 810; in S432, a layer of carbon 60 (C60) is deposited on the passivation layer 710 as the electron transport layer 810; C60 is an excellent electron acceptor material with high electron mobility and good stability; it can effectively collect and transport electrons from the perovskite light-absorbing layer while blocking the transport of holes, thus realizing the effective separation of electrons and holes; in addition, C60 can also form good interfacial contact with the perovskite light-absorbing layer and the passivation layer 710, which helps to reduce the charge recombination at the interface; in S433, a protective layer 910 is deposited on the electron transport layer 810 by an atomic layer deposition device; the protective layer 910 is usually composed of inorganic materials (such as tin dioxide, aluminum oxide, etc.) and has excellent chemical stability and mechanical strength; it can effectively protect the perovskite light-absorbing layer and the electron transport layer 810 from being eroded by the external environment (such as water, oxygen, ultraviolet rays, etc.), thereby improving the long-term stability of the solar cell; in addition, the protective layer 910 can also play a certain role in optical regulation, which helps to optimize the spectral response of the solar cell; by sequentially preparing the passivation layer 710, the electron transport layer 810 and the protective layer 910, a perovskite tandem solar cell with a complete structure and excellent performance can be constructed; this structure can not only effectively improve the conversion efficiency of the solar cell, but also significantly enhance its long-term stability; in addition, the flexibility and adjustability of this preparation method also provide more possibilities for the research and development of perovskite solar cells.

[0087] S500: A first transparent conductive oxide thin film layer 1010 is deposited on the protective layer 910 by physical vapor deposition, and a second transparent conductive oxide thin film layer 1020 is deposited on the second doped silicon thin film layer 320.

[0088] Specifically, the first transparent conductive oxide thin film layer 1010 and the second transparent conductive oxide thin film layer 1020 can be one of indium tin oxide thin film, tungsten-doped indium oxide thin film, doped tin oxide thin film, doped aluminum oxide thin film.

[0089] S600: A first copper electrode 1110 is prepared on the first transparent conductive oxide thin film layer 1010 by an edge protection treatment method and an electroplating treatment method, and a second copper electrode 1120 is prepared on the second transparent conductive oxide thin film layer 1020.

[0090] Among them, the edge protection treatment method is to protect the perovskite light-absorbing layer when preparing the first copper electrode 1110 and the second copper electrode 1120;

[0091] Further, in S600, the edge protection treatment method and the electroplating treatment method are used to prepare the first copper electrode 1110 on the first transparent conductive oxide thin film layer 1010 and the second copper electrode 1120 on the second transparent conductive oxide thin film layer 1020; specifically:

[0092] S610: Deposit the first seed layer on the first transparent conductive oxide thin film layer 1010 and the second seed layer on the second transparent conductive oxide thin film layer 1020 by physical vapor deposition;

[0093] S620: Print the first mask layer on the first seed layer and the second mask layer on the second seed layer by printing;

[0094] S630: Use photosensitive ink to perform the first edge protection on the sides of the double-sided textured silicon wafer 100 printed with the first mask layer and the second mask layer;

[0095] S640: Expose and develop the double-sided textured silicon wafer 100 after edge protection to obtain the first grid line trench on the first mask layer and the second grid line trench on the second mask layer;

[0096] S650: Electroplate the first copper electrode 1110 on the first grid line trench and the second copper electrode 1120 in the second grid line trench by electroplating;

[0097] S660: Place the double-sided textured silicon wafer 100 prepared with the first copper electrode 1110 and the second copper electrode 1120 into an alkaline solution to remove the first mask layer and the second mask layer, and at the same time, the photosensitive ink for the first edge protection will also be removed;

[0098] S670: Use photosensitive ink to perform the second edge protection on the sides of the double-sided textured silicon wafer 100 after removing the first mask layer and the second mask layer, and form an edge layer 1300 on the sides of the double-sided textured silicon wafer 100;

[0099] S680: Place the double-sided textured silicon wafer 100 after the second edge protection into an acidic solution to remove the first seed layer and the second seed layer.

[0100] It should be noted that in S610, a first seed layer with a thickness of 10 nm - 150 nm is deposited on the first transparent conductive oxide thin film layer 1010 by physical vapor deposition (PVD), and a second seed layer with a thickness of 10 nm - 150 nm is deposited on the second transparent conductive oxide thin film layer 1020; in S620, a photosensitive ink is printed on the first seed layer as the first mask layer, and a photosensitive ink is printed on the second seed layer as the second mask layer; in S630, the side edges of the double-sided textured silicon wafer 100 printed with the first mask layer and the second mask layer are protected by a first edge coating with photosensitive ink, and the double-sided textured silicon wafer 100 and multiple structural layers prepared on the first and second surfaces are subjected to a first edge coating treatment so that their four peripheral edges are protected; in S640, exposure treatment and development treatment are respectively performed on the first mask layer and the second mask layer of the double-sided textured silicon wafer 100 after edge coating protection using a lithography machine, a first gate line trench is obtained on the first mask layer, and a second gate line trench is obtained on the second mask layer; then, in S650, a first copper electrode 1110 is electroplated on the first gate line trench, and a second copper electrode 1120 is electroplated in the second gate line trench; wherein, the first copper electrode 1110 includes multiple first main gates with a width of 50 μm - 80 μm and a thickness of 5 μm - 20 μm, and multiple first sub-gates perpendicular to the first main gates with a width of 10 μm - 40 μm and a thickness of 5 μm - 20 μm; the second copper electrode 1120 includes multiple second main gates with a width of 50 μm - 250 μm and a thickness of 5 μm - 20 μm, and multiple second sub-gates perpendicular to the second main gates with a width of 20 μm - 80 μm and a thickness of 5 μm - 20 μm; after the first copper electrode 1110 and the second copper electrode 1120 are formed, in S660, the double-sided textured silicon wafer 100 prepared with the first copper electrode 1110 and the second copper electrode 1120 is placed in an alkaline solution containing potassium hydroxide or sodium hydroxide for reaction for 30 s - 200 s. At this time, the first mask layer and the second mask layer will be removed, and the photosensitive ink for the first edge coating protection will also be removed. However, due to strictly controlling the reaction time to 30 s - 200 s, the double-sided textured silicon wafer 100 with edge coating protection and multiple structural layers prepared on the first and second surfaces will not be corroded by the alkaline solution; through the second edge coating protection of the side edges of the double-sided textured silicon wafer 100 after removing the first mask layer and the second mask layer using photosensitive ink in S670, the double-sided textured silicon wafer 100 and multiple structural layers prepared on the first and second surfaces are subjected to a second edge coating treatment so that their four peripheral edges are protected again; finally, in S680, the double-sided textured silicon wafer 100 after the second edge coating protection is placed in a dilute sulfuric acid or dilute nitric acid solution for reaction for 30 s - 100 s to remove the first seed layer and the second seed layer, and the double-sided textured silicon wafer 100 after removing the first seed layer and the second seed layer is cleaned and dried.

[0101] It should be noted that, through physical vapor deposition, S610 deposited a first seed layer and a second seed layer on the first transparent conductive oxide thin film layer 1010 and the second transparent conductive oxide thin film layer 1020 respectively; these seed layers provided a necessary conductive substrate for the subsequent electroplating process, ensuring that copper ions could be deposited uniformly and effectively at the designated positions; S620 used a printing method to print a first mask layer and a second mask layer on the first seed layer and the second seed layer respectively; the design of the mask layer precisely controlled the shape, size, and position of the copper electrodes, providing precise pattern guidance for the subsequent electroplating process; S630 performed the first edge protection on the side edges of the double-sided textured silicon wafer 100 using photosensitive ink; this step effectively prevented the perovskite light-absorbing layer in the double-sided textured silicon wafer 100 from being corroded or contaminated during the subsequent exposure, development, and electroplating processes, ensuring the quality and reliability of the product; S640 formed a first grid line groove and a second grid line groove on the first mask layer and the second mask layer respectively through exposure and development; these grooves provided precise paths and shapes for the subsequent electroplating of copper electrodes; S650 used electroplating to electroplate a first copper electrode 1110 and a second copper electrode 1120 in the first grid line groove and the second grid line groove respectively. The electroplated copper electrodes have the advantages of good conductivity, low cost, and easy processing, and can meet the requirements of the solar cell for electrode performance; S660 placed the double-sided textured silicon wafer 100 with the prepared copper electrodes into an alkaline solution to remove the first mask layer and the second mask layer, and at the same time removed the photosensitive ink for the first edge protection; S670 performed the second edge protection on the side edges of the double-sided textured silicon wafer 100 after removing the mask layer to obtain an edge protection layer 1300; this step further protected the perovskite light-absorbing layer in the double-sided textured silicon wafer 100 from being corroded or contaminated during the process of removing the seed layers; S680 placed the double-sided textured silicon wafer 100 after the second edge protection into an acidic solution to remove the first seed layer and the second seed layer; this step is the last step in the preparation of the copper electrodes, ensuring that the final copper electrodes have a clear and complete structure.

[0102] S700: Prepare an antireflection layer 1210 in the area other than the first copper electrode 1110 on the first transparent conductive oxide thin film layer 1010 to obtain a perovskite tandem solar cell.

[0103] Specifically, the antireflection layer 1210 is a magnesium fluoride layer with a thickness of 120 nm.

[0104] According to the preparation method of a perovskite tandem solar cell of this embodiment, the beneficial effects are as follows:

[0105] Through double-sided texturing treatment, a textured surface structure is formed on the silicon wafer surface, increasing the diffuse reflection of light, enabling more sunlight energy to be captured by the silicon wafer, thereby improving the light absorption efficiency of the solar cell; multi-layer thin film structures are prepared on both sides of the silicon wafer, including an intrinsic amorphous silicon thin film layer, a doped silicon thin film layer, a composite layer, a hole transport layer, etc.; these thin film layers contribute to the effective separation and transport of charges, reducing charge recombination losses, thereby improving the conversion efficiency of the solar cell; a perovskite light-absorbing layer is prepared by the solution spin-coating method, which can precisely control the thickness and uniformity of the perovskite layer, thereby improving the light absorption efficiency and charge collection efficiency; at the same time, the introduction of a passivation layer can further reduce the recombination of charges at the interface and improve the performance of the solar cell; a transparent conductive oxide thin film layer is prepared by physical vapor deposition, and the thin film prepared by this method has good conductivity and light transmittance, which is beneficial to the collection and transport of charges; at the same time, the transparent conductive thin film layer can also protect the underlying thin film structure and improve the stability of the solar cell; a copper electrode is prepared by the edge protection treatment method and the electroplating treatment method, which can protect the perovskite light-absorbing layer from damage while preparing the electrode and avoid the influence on the performance of the solar cell during the electrode preparation process; compared with atomic layer deposition technology, the edge protection treatment method can not only save equipment costs but also does not need to worry about production capacity problems and is suitable for large-scale industrialization; an antireflection layer is prepared on the first transparent conductive oxide thin film layer, which can reduce the reflection of light, enable more sunlight to enter the interior of the solar cell and be absorbed, thereby improving the light utilization rate and the conversion efficiency of the solar cell.

[0106] Example Two

[0107] A perovskite tandem solar cell is prepared by the preparation method of a perovskite tandem solar cell in Example One.

[0108] According to the perovskite tandem solar cell of this embodiment, it includes the preparation method of a perovskite tandem solar cell provided in Example One, and thus has all the beneficial effects of the preparation method of this perovskite tandem solar cell, which will not be elaborated here.

[0109] In this application, the term "a plurality of" refers to two or more, unless otherwise clearly defined. Terms such as "installed", "connected", "connected to", "fixed" and other terms should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; "connected" can be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0110] In the description of this specification, the descriptions of terms such as "one embodiment", "some embodiments", "specific embodiments", etc. mean that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations 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 one or more embodiments or examples in a suitable manner.

[0111] The above are only the preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, various changes and modifications can be made to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within the protection scope of the present application.

Claims

1. A preparation method of a perovskite tandem solar cell, characterized in that, The method includes: Placing a silicon wafer in an alkaline solution to obtain a double-sided textured silicon wafer, and cleaning the double-sided textured silicon wafer; On the first side of the double-sided textured silicon wafer, successively preparing a first intrinsic amorphous silicon thin film layer, a first doped silicon thin film layer, a composite layer, and a hole transport layer; On the second side of the double-sided textured silicon wafer opposite to the first side, successively preparing a second intrinsic amorphous silicon thin film layer and a second doped silicon thin film layer; Using the solution spin-coating method to prepare a perovskite light-absorbing layer on the hole transport layer, and successively preparing a passivation layer, an electron transport layer, and a protective layer on the perovskite light-absorbing layer; Using physical vapor deposition to deposit a first transparent conductive oxide thin film layer on the protective layer and a second transparent conductive oxide thin film layer on the second doped silicon thin film layer; Using an edge protection treatment method and an electroplating treatment method to prepare a first copper electrode on the first transparent conductive oxide thin film layer and a second copper electrode on the second transparent conductive oxide thin film layer. The edge protection treatment method is to protect the perovskite light-absorbing layer when preparing the first copper electrode and the second copper electrode; Preparing an antireflection layer in the area other than the first copper electrode on the first transparent conductive oxide thin film layer to obtain a perovskite tandem solar cell.

2. The preparation method of a perovskite tandem solar cell according to claim 1, characterized in that, The perovskite light-absorbing layer can be any one of a first perovskite light-absorbing layer and a second perovskite light-absorbing layer.

3. The preparation method of a perovskite tandem solar cell according to claim 2, wherein Using the solution spin-coating method to prepare the first perovskite light-absorbing layer on the hole transport layer, specifically: Dissolving formamidinium iodide, formamidinium bromide, and formamidinium chloride in an isopropyl alcohol solution in a ratio of 3:1:2 to obtain a first organic amine solution; Simultaneously evaporating and covering lead iodide and cesium bromide on the surface of the hole transport layer through a thermal evaporation device to form an inorganic layer on the surface of the hole transport layer; Placing the double-sided textured silicon wafer with the prepared inorganic layer into a nitrogen protection box, uniformly dropping the first organic amine solution on the inorganic layer, and setting the rotation speed and rotation time to rotate the double-sided textured silicon wafer; Taking out the double-sided textured silicon wafer from the nitrogen protection box and performing annealing heat treatment to obtain the double-sided textured silicon wafer with the first perovskite light-absorbing layer prepared.

4. The preparation method of a perovskite tandem solar cell according to claim 2, characterized in that, Using the solution spin-coating method to prepare the second perovskite light-absorbing layer on the hole transport layer, specifically: Dissolving formamidinium iodide, formamidinium bromide, formamidinium chloride, lead iodide, and cesium bromide in an ethanol solution in a ratio of 3:1:1:5:2 to obtain a second organic amine solution; Placing the double-sided textured silicon wafer with the prepared hole transport layer into a nitrogen protection box, uniformly dropping the second organic amine solution on the inorganic layer, and setting the rotation speed and rotation time to rotate the double-sided textured silicon wafer; Taking out the double-sided textured silicon wafer from the nitrogen protection box and performing annealing heat treatment to obtain the double-sided textured silicon wafer with the second perovskite light-absorbing layer prepared.

5. The preparation method of a perovskite tandem solar cell according to claim 1, characterized in that, Successively preparing a passivation layer, an electron transport layer, and a protective layer on the perovskite light-absorbing layer; Specifically, Placing the double-sided textured silicon wafer with the prepared perovskite light-absorbing layer into a mask plate to deposit a layer of lithium fluoride to obtain the passivation layer; Deposit a layer of C60 on the passivation layer to obtain the electron transport layer; Put the double-sided textured silicon wafer with the prepared electron transport layer into an atomic layer deposition device, and obtain the protective layer through the alternating purge of a tin source and a water source.

6. The preparation method of a perovskite tandem solar cell according to claim 1, characterized in that, Prepare a first copper electrode on the first transparent conductive oxide thin film layer and a second copper electrode on the second transparent conductive oxide thin film layer by using an edge protection treatment method and an electroplating treatment method; Specifically: Deposit a first seed layer on the first transparent conductive oxide thin film layer and a second seed layer on the second transparent conductive oxide thin film layer by using physical vapor deposition; Print a first mask layer on the first seed layer and a second mask layer on the second seed layer by using a printing method; Use photosensitive ink to perform the first edge protection on the sides of the double-sided textured silicon wafer with the first mask layer and the second mask layer printed; Perform exposure and development on the double-sided textured silicon wafer after the edge protection to obtain a first gate line trench on the first mask layer and a second gate line trench on the second mask layer; Electroplate the first copper electrode on the first gate line trench and electroplate the second copper electrode in the second gate line trench by using electroplating; Put the double-sided textured silicon wafer with the first copper electrode and the second copper electrode prepared into an alkaline solution to remove the first mask layer and the second mask layer, and at the same time, the photosensitive ink for the first edge protection will also be removed; Use photosensitive ink to perform the second edge protection on the sides of the double-sided textured silicon wafer after removing the first mask layer and the second mask layer, and form an edge protection layer on the sides of the double-sided textured silicon wafer; Put the double-sided textured silicon wafer after the second edge protection into an acidic solution to remove the first seed layer and the second seed.

7. A method for preparing a perovskite tandem solar cell according to claim 1, characterized in that The first doped silicon thin film layer is a phosphorus-doped silicon thin film layer; the second doped silicon thin film layer is a boron-doped silicon thin film layer.

8. The preparation method of a perovskite tandem solar cell according to claim 1, characterized in that, The first transparent conductive oxide thin film layer and the second transparent conductive oxide thin film layer can be one of indium tin oxide thin film, tungsten-doped indium oxide thin film, doped tin oxide thin film, and doped aluminum oxide thin film.

9. The preparation method of a perovskite tandem solar cell according to claim 1, wherein The hole transport layer is a nickel oxide layer.

10. A perovskite tandem solar cell, characterized in that, Prepared by the preparation method of a perovskite tandem solar cell according to any one of claims 1-9.

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