Perovskite / crystalline silicon laminated solar cell and preparation method thereof
By introducing water vapor into the mixed gas during magnetron sputtering to decompose and generate hydroxyl radicals, the problem of weak bonding between TCO thin films and SAM or perovskite layers is solved, thus improving the stability and efficiency of perovskite/crystalline silicon tandem solar cells.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-12
- Publication Date
- 2026-04-07
AI Technical Summary
In existing technologies, the bonding force between the TCO thin film and the SAM layer or perovskite layer is weak, making it difficult to improve the long-term stability and photoelectric conversion efficiency of perovskite/crystalline silicon tandem solar cells.
During magnetron sputtering, a mixed gas containing water vapor is introduced, and hydroxyl radicals are generated by plasma field decomposition, which increases the hydroxyl content on the surface of the TCO film and improves its interfacial bonding with the SAM layer or perovskite active material layer.
This enhances the adhesion between the TCO thin film and the SAM layer or perovskite active material layer, thereby improving the long-term stability and photoelectric conversion efficiency of perovskite/crystalline silicon tandem solar cells.
Smart Images
Figure CN121815888A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of solar cell fabrication technology, and more specifically, to a perovskite / crystalline silicon tandem solar cell and its fabrication method. Background Technology
[0002] Perovskite solar cells have attracted widespread attention in the photovoltaic field due to their high efficiency, low cost, and tunable bandgap characteristics. In recent years, perovskite-silicon tandem solar cells have emerged as a novel type of high-efficiency solar cell, with theoretical photoelectric conversion efficiencies exceeding 40%, far surpassing those of currently commercialized single-crystal silicon solar cells. However, optimizing the performance and improving the stability of tandem solar cells still faces many challenges, one of the key being the surface modification of the transparent conductive oxide (TCO) film and ensuring good interfacial contact with subsequent layers.
[0003] TCO thin films, such as indium tin oxide (ITO) and zinc tin oxide (IZO), are commonly used as transparent oxide conductive layers in perovskite solar cells. However, the bonding between TCO thin films and self-assembled monolayers (SAM layers) or perovskite active material layers is relatively weak. This is mainly due to the lack of sufficient active sites, such as hydroxyl groups (-OH), on the surface of TCO thin films. The presence of hydroxyl groups can not only enhance the physical adsorption of TCO and SAM, but also improve their chemical bonding through the formation of hydrogen bonds, thereby increasing the stability of the entire stacked structure.
[0004] Currently, the main method to increase the hydroxyl content on the surface of TCO thin films is post-treatment, such as steam treatment or plasma treatment, after deposition. However, these methods generally have the following problems: First, it is difficult to achieve large-area uniform coverage during the treatment process, especially in the fabrication of large-size devices, where controlling the treatment conditions becomes particularly difficult; second, the treatment conditions are not easy to precisely control, leading to fluctuations in hydroxyl content and affecting the consistency and stability of the film performance; third, some treatment conditions may damage the deposited film, reducing its electrical and optical properties.
[0005] Based on this, it is urgent to research and develop a new method to increase the hydroxyl content on the surface of TCO thin films, so as to enhance the interfacial bonding force between them and the SAM layer or perovskite active material layer, while ensuring the large-area uniformity and performance stability of the thin film. This is of great significance for improving the electrochemical performance of perovskite / crystalline silicon tandem solar cells. Summary of the Invention
[0006] The main objective of this invention is to provide a perovskite / crystalline silicon tandem solar cell and its preparation method, in order to solve the problem in the prior art that the bonding force between the TCO thin film and the SAM layer or perovskite layer is weak, and that it is easy to delaminate and fall off, which makes it difficult to improve the long-term stability and photoelectric conversion efficiency of the perovskite / crystalline silicon tandem solar cell.
[0007] To achieve the above objectives, the present invention provides a perovskite / crystalline silicon tandem solar cell, comprising a crystalline silicon base cell, a first transparent oxide conductive layer, an optional self-assembled monolayer, a perovskite active material layer, an electron transport layer, a buffer layer, a second transparent oxide conductive layer, and a metal electrode layer, which are sequentially stacked. The crystalline silicon base cell has a pyramidal textured structure, and the first transparent oxide conductive layer, the optional self-assembled monolayer, the perovskite active material layer, the electron transport layer, the buffer layer, and the second transparent oxide conductive layer are all conformally aligned with the crystalline silicon base cell. The method for preparing the first transparent oxide conductive layer includes: using the crystalline silicon base cell as a substrate, using one or more of indium tin oxide, zinc oxide, and aluminum-doped zinc oxide as a target material, performing magnetron sputtering in a mixed gas containing water vapor, and then obtaining the first transparent oxide conductive layer after heat treatment.
[0008] Furthermore, the flow rate of the mixed gas is 200–300 sccm; preferably, the partial pressure of water vapor in the mixed gas is 0.1–1 Pa.
[0009] Further, the mixed gas is a mixture of water vapor, argon, oxygen and hydrogen; preferably, the mixed gas is a mixture of water vapor, argon, oxygen and hydrogen in a volume ratio of 1:(31-34):1:(14-17).
[0010] Furthermore, the magnetron sputtering temperature is 130–200℃, the power is 0.2–0.6kW, the sputtering rate is 3–6mm / s, and the gas pressure is 10. -4 ~10 -5 Pa.
[0011] Furthermore, the thickness of the first transparent oxide conductive layer is 10–20 nm.
[0012] Furthermore, the heat treatment temperature is 110–160℃, and the time is 15–20 min.
[0013] Furthermore, the perovskite / crystalline silicon tandem solar cell includes a self-assembled monolayer with a thickness of 3–5 nm; preferably, the material of the self-assembled monolayer is selected from one or more of (2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl)phosphoric acid, [4-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl)phosphoric acid, and [4-(7H-dibenzocarbazole-7-yl)butyl]phosphoric acid.
[0014] Furthermore, the self-assembled monolayers are prepared by vapor deposition or spraying.
[0015] Further, the crystalline silicon bottom cell is selected from HJT bottom cells, TOPCon bottom cells, or ABC bottom cells; preferably, the average height of the pyramidal textured structure in the crystalline silicon bottom cell is 1.7–2.5 μm; preferably, the thickness of the perovskite active material layer is 700–900 nm, and the material is selected from materials formed by the hybridization of inorganic and organic salts; wherein, the inorganic salt is selected from PbI2 and / or CsBr, and the organic salt is selected from FAI and / or MAI; preferably, the thickness of the electron transport layer is 10–20 nm, and the material is selected from TiO2, PCBM, and C 60 One or more of the following: preferably, the thickness of the buffer layer is 20-30 nm, and its material is selected from SnO2 and / or Al2O3; preferably, the thickness of the second transparent oxide conductive layer is 30-40 nm, and its material is selected from indium tin oxide or zinc oxide; preferably, the thickness of the metal electrode layer is selected from 120-150 nm, and its material is selected from one or more of Au, Ag, Cu and Al.
[0016] To achieve the above objectives, another aspect of the present invention provides a method for fabricating the perovskite / crystalline silicon tandem solar cell provided in this application. The method includes: step S1, preparing a crystalline silicon base cell; step S2, sequentially fabricating a first transparent oxide conductive layer, an optional self-assembled monolayer, a perovskite active material layer, an electron transport layer, a buffer layer, a second transparent oxide conductive layer, and a metal electrode layer on one side surface of the crystalline silicon base cell; wherein, the method for fabricating the first transparent oxide conductive layer includes: using the crystalline silicon base cell as a substrate, using one or more of indium tin oxide, zinc oxide, and aluminum-doped zinc oxide as a target material, performing magnetron sputtering in a mixed gas containing water vapor, and obtaining the first transparent oxide conductive layer after heat treatment.
[0017] By applying the technical solution of the present invention, a mixed gas containing water vapor is introduced during the magnetron sputtering process, and the mixed gas is decomposed under the action of the plasma field to generate hydroxyl radicals (-OH). These hydroxyl radicals meet with the particles generated by the sputtering of the target material and undergo a chemical reaction to generate transparent oxide conductive material particles, which are deposited on one side surface of the crystalline silicon bottom cell. Then, the first transparent oxide conductive layer is obtained by heat treatment.
[0018] Traditional magnetron sputtering methods for preparing the first transparent oxide conductive layer typically require an inert atmosphere to avoid target oxidation and the introduction of impurities. However, this application introduces water vapor into the reaction, which can increase the hydroxyl content on the surface of the first transparent oxide conductive layer, improve its interfacial properties, thereby enhancing its bonding force with the self-assembled monolayer (SAM layer) or perovskite active material layer, inhibiting film shedding, and thus improving the long-term stability and photoelectric conversion efficiency of perovskite / crystalline silicon tandem solar cells. Attached Figure Description
[0019] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:
[0020] Figure 1 A schematic diagram of the stacked structure of the perovskite / crystalline silicon tandem solar cell provided in this application is shown.
[0021] The above figures include the following reference numerals:
[0022] 10. Crystalline silicon bottom cell; 20. First transparent oxide conductive layer; 30. Self-assembled monolayer; 40. Perovskite active material layer; 50. Electron transport layer; 60. Buffer layer; 70. Second transparent oxide conductive layer; 80. Metal electrode layer. Detailed Implementation
[0023] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the embodiments.
[0024] As described in the background section, existing perovskite / crystalline silicon tandem solar cells suffer from weak adhesion between the TCO thin film and the SAM layer or perovskite active material layer, leading to easy delamination and detachment. This results in difficulties in improving the long-term stability and photoelectric conversion efficiency of perovskite / crystalline silicon tandem solar cells. To address these technical problems, the first aspect of this application provides a perovskite / crystalline silicon tandem solar cell, such as... Figure 1 As shown, the perovskite / crystalline silicon tandem solar cell includes a crystalline silicon base cell 10, a first transparent oxide conductive layer 20, an optional self-assembled monolayer 30, a perovskite active material layer 40, an electron transport layer 50, a buffer layer 60, a second transparent oxide conductive layer 70, and a metal electrode layer 80, which are stacked sequentially. The crystalline silicon base cell 10 has a pyramidal textured structure. The first transparent oxide conductive layer 20, the optional self-assembled monolayer 30, the perovskite active material layer 40, the electron transport layer 50, the buffer layer 60, and the second transparent oxide conductive layer 70 are all conformally aligned with the crystalline silicon base cell 10. The preparation method of the first transparent oxide conductive layer 20 includes: using the crystalline silicon base cell 10 as a substrate, using one or more of indium tin oxide, zinc oxide, and aluminum-doped zinc oxide as a target, performing magnetron sputtering in a mixed gas containing water vapor, and then obtaining the first transparent oxide conductive layer 20 after heat treatment.
[0025] In the preparation method of the first transparent oxide conductive layer 20 of this application, a mixed gas containing water vapor is introduced during the magnetron sputtering process, and the mixed gas is decomposed under the action of the plasma field to generate hydroxyl radicals (-OH). These hydroxyl radicals meet with the particles generated by the sputtering of the target material and undergo a chemical reaction to generate transparent oxide conductive material particles, which are deposited on one side surface of the crystalline silicon bottom cell 10. Then, the first transparent oxide conductive layer 20 is obtained by heat treatment.
[0026] Traditional magnetron sputtering methods for preparing the first transparent oxide conductive layer 20 typically require an inert atmosphere to avoid target oxidation and the introduction of impurities. However, this application introduces water vapor into the reaction, which can increase the hydroxyl content on the surface of the first transparent oxide conductive layer 20, improve its interfacial properties, thereby enhancing its bonding force with the self-assembled monolayer 30 (SAM layer) or the perovskite active material layer 40, inhibiting film shedding, and thus improving the long-term stability and photoelectric conversion efficiency of the perovskite / crystalline silicon tandem solar cell.
[0027] It should be noted that the perovskite / crystalline silicon tandem solar cell in this application refers to a tandem solar cell in which a top cell and a bottom cell are connected in series; wherein, the bottom cell is the crystalline silicon bottom cell 10 mentioned above; the top cell is a perovskite top cell, which includes a first transparent oxide conductive layer 20, an optional self-assembled monolayer 30, a perovskite active material layer 40, an electron transport layer 50, a buffer layer 60, a second transparent oxide conductive layer 70, and a metal electrode layer 80 stacked together.
[0028] In a preferred embodiment, the flow rate of the mixed gas is 200–300 sccm. The flow rate of the mixed gas includes, but is not limited to, the above range. Limiting it to this range is beneficial for increasing the amount of hydroxyl radicals generated by decomposition, increasing the generation rate of transparent oxide conductive material particles, and improving the interfacial bonding between the first transparent oxide conductive layer 20 and the self-assembled monolayer 30 or perovskite active material layer 40. This, in turn, helps improve the long-term stability and photoelectric conversion efficiency of the perovskite / crystalline silicon tandem solar cell.
[0029] In a preferred embodiment, the partial pressure of water vapor in the mixed gas is 0.1 to 1 Pa. The partial pressure of water vapor in the mixed gas includes, but is not limited to, the above range. Limiting it to this range is beneficial for improving the reaction efficiency between hydroxyl radicals and particles generated by target sputtering, thereby increasing the generation rate of transparent oxide conductive material particles. This is beneficial for improving the interfacial bonding force between the first transparent oxide conductive layer 20 and the self-assembled monolayer 30 or perovskite active material layer 40, thereby improving the long-term stability and photoelectric conversion efficiency of the perovskite / crystalline silicon tandem solar cell.
[0030] In order to improve the purity of the first transparent oxide conductive layer 20 and to avoid uneven distribution of hydroxyl groups therein, in a preferred embodiment, the mixed gas is a mixture of water vapor, argon, oxygen and hydrogen.
[0031] In order to improve the purity of the first transparent oxide conductive layer 20 and to avoid uneven distribution of hydroxyl groups therein, thereby further improving the interfacial bonding force between the first transparent oxide conductive layer 20 and the self-assembled monolayer 30 or the perovskite active material layer 40, preferably, the mixed gas is a mixture of water vapor, argon, oxygen and hydrogen in a volume ratio of 1:(31-34):1:(14-17).
[0032] In a preferred embodiment, the magnetron sputtering temperature is 130–200°C, the power is 0.2–0.6 kW, the sputtering rate is 3–6 mm / s, and the gas pressure is 10. -4 ~10 -5 Pa. Compared to other process conditions, magnetron sputtering using the above process parameters is beneficial for particle collision and thin film growth, which is beneficial for improving magnetron sputtering efficiency and the film quality of the first transparent oxide conductive layer 20, reducing impurity incorporation, and improving the purity of the first transparent oxide conductive layer 20; at the same time, it is also beneficial for improving production efficiency and large-scale production.
[0033] In a preferred embodiment, the thickness of the first transparent oxide conductive layer 20 is 10–20 nm. The thickness of the first transparent oxide conductive layer 20 includes, but is not limited to, the above range. Limiting it to the above range is beneficial to improving the carrier transport efficiency of the first transparent oxide conductive layer 20, and at the same time, it is beneficial to improve the transparency of the first transparent oxide conductive layer 20.
[0034] In order to improve the carrier transport efficiency of the first transparent oxide conductive layer 20 and at the same time improve its transparency, the material of the first transparent oxide conductive layer 20 is preferably one or more of indium tin oxide, zinc oxide and aluminum-doped zinc oxide.
[0035] In a preferred embodiment, the heat treatment temperature is 110–160°C, and the time is 15–20 min. The heat treatment temperature and time include, but are not limited to, the above ranges. Limiting them within these ranges is beneficial for promoting the growth and rearrangement of deposited particles, optimizing the microstructure of the first transparent oxide conductive layer 20, improving the uniformity of hydroxyl distribution, and improving the interfacial bonding force between the first transparent oxide conductive layer 20 and the self-assembled monolayer 30. This, in turn, helps to improve the long-term stability and photoelectric conversion efficiency of the perovskite / crystalline silicon tandem solar cell.
[0036] In a preferred embodiment, the perovskite / crystalline silicon tandem solar cell includes a self-assembled monolayer 30 with a thickness of 3–5 nm. The thickness of the self-assembled monolayer 30 includes, but is not limited to, the above range. Limiting it to this range helps to effectively passivate surface defects and reduce non-radiative recombination, thereby improving the photoelectric conversion efficiency of the perovskite / crystalline silicon tandem solar cell.
[0037] To further leverage the passivation effect of the self-assembled monolayer 30 on surface defects and reduce non-radiative recombination, thereby improving the photoelectric conversion efficiency of perovskite / crystalline silicon tandem solar cells, preferably, the material of the self-assembled monolayer 30 includes, but is not limited to, one or more of (2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl)phosphoric acid (MeO-2PACz), [4-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl)phosphoric acid (MeO-4PACz), and [4-(7H-dibenzocarbazole-7-yl)butyl]phosphoric acid (4PADCB).
[0038] In a preferred embodiment, the self-assembled monolayer 30 is prepared by vapor deposition or spraying. Compared to other methods, preparing the self-assembled monolayer 30 by the above method is beneficial for uniform material coverage and large-area production, thereby facilitating its passivation of surface defects and reducing non-radiative recombination, thus improving the photoelectric conversion efficiency of perovskite / crystalline silicon tandem solar cells.
[0039] This application may employ crystalline silicon solar cells 10 of commonly used types in the art. In a preferred embodiment, the crystalline silicon solar cell 10 includes, but is not limited to, HJT solar cells (heterojunction solar cells), TOPCon solar cells (tunneling oxide passivated contact solar cells), or ABC solar cells (full back contact solar cells).
[0040] To meet commercial needs, preferably, the average height of the pyramidal textured structure in the crystalline silicon bottom cell 10 is 1.7 to 2.5 μm.
[0041] In a preferred embodiment, the thickness of the perovskite active material layer 40 is 700–900 nm, and its material includes, but is not limited to, materials formed by the hybridization of inorganic and organic salts; wherein, the inorganic salts include, but are not limited to, PbI2 and / or CsBr, and the organic salts include, but are not limited to, FAI and / or MAI. The thickness and material of the perovskite active material layer 40 are not limited to the above-mentioned ranges. Limiting it to these ranges is beneficial for improving the efficiency of photogenerated electrons and holes, and for facilitating the extraction of electrons and holes, thereby improving the photoelectric conversion efficiency of the perovskite / crystalline silicon tandem solar cell.
[0042] The perovskite active material layer 40 in this application can be prepared by vapor deposition combined with spin coating, vapor deposition, or vapor deposition combined with blade coating.
[0043] In a preferred embodiment, the electron transport layer 50 has a thickness of 10–20 nm, and its material includes, but is not limited to, TiO2, PCBM, and C. 60 One or more of the above. The thickness and material of the electron transport layer 50 include, but are not limited to, the ranges described above. Limiting it to the ranges described above is beneficial to improving electron transport efficiency, thereby improving the photoelectric conversion efficiency of the perovskite / silicon tandem solar cell.
[0044] The electron transport layer 50 in this application can be prepared by vapor deposition or atomic layer deposition (ALD).
[0045] In a preferred embodiment, the thickness of the buffer layer 60 is 20–30 nm, and its material includes, but is not limited to, SnO2 and / or Al2O3. The thickness and material of the buffer layer 60 are not limited to the above range; limiting it within this range facilitates the preparation of subsequent film layers and reduces damage to the battery film layer during the preparation of the second transparent oxide conductive layer 70.
[0046] The buffer layer 60 in this application can be prepared by atomic vapor deposition (ALD) or spraying.
[0047] In a preferred embodiment, the thickness of the second transparent oxide conductive layer 70 is 30–40 nm, and its material includes, but is not limited to, indium tin oxide or zinc oxide. Compared to other ranges, limiting the thickness of the second transparent oxide conductive layer 70 to the above range is beneficial to improving its conductivity, thereby improving the photoelectric conversion efficiency of the perovskite / crystalline silicon tandem solar cell. At the same time, using the above-mentioned materials as the material for the second transparent oxide conductive layer 70 also helps to improve the photoelectric conversion efficiency of the perovskite / crystalline silicon tandem solar cell while reducing the fabrication difficulty.
[0048] The second transparent oxide conductive layer 70 in this application can be prepared by magnetron sputtering.
[0049] In a preferred embodiment, the thickness of the metal electrode layer 80 is, but is not limited to, 120–150 nm, and its material is, but is not limited to, one or more of Au, Ag, Cu, and Al. Limiting the thickness and material of the metal electrode layer 80 to the above range is beneficial for improving its conductivity and suppressing secondary absorption, thereby improving the photoelectric conversion efficiency of the perovskite / silicon tandem solar cell.
[0050] The metal electrode layer 80 in this application can be prepared by vapor deposition or screen printing. For patterned deposition, it is preferable to use a mask to prepare the metal electrode layer 80 during the vapor deposition process.
[0051] The second aspect of this application also provides a method for fabricating the perovskite / crystalline silicon tandem solar cell provided in this application. The method includes: step S1, preparing a crystalline silicon base cell 10; step S2, sequentially fabricating a first transparent oxide conductive layer 20, an optional self-assembled monolayer 30, a perovskite active material layer 40, an electron transport layer 50, a buffer layer 60, a second transparent oxide conductive layer 70, and a metal electrode layer 80 on one side surface of the crystalline silicon base cell 10; wherein, the method for fabricating the first transparent oxide conductive layer 20 includes: using the crystalline silicon base cell 10 as a substrate, using one or more of indium tin oxide, zinc oxide, and aluminum-doped zinc oxide as a target material, performing magnetron sputtering in a mixed gas containing water vapor, and obtaining the first transparent oxide conductive layer 20 after heat treatment.
[0052] In the preparation method of the first transparent oxide conductive layer 20 described in this application, the introduction of water vapor to participate in the reaction can increase the hydroxyl content on the surface of the first transparent oxide conductive layer 20, improve its interface properties, thereby increasing its bonding force with the self-assembled monolayer 30 (SAM layer) or the perovskite active material layer 40, inhibiting the shedding of the film layer, and thus improving the long-term stability and photoelectric conversion efficiency of the perovskite / crystalline silicon tandem solar cell.
[0053] The present application will be further described in detail below with reference to specific embodiments, which should not be construed as limiting the scope of protection claimed in the present application.
[0054] Example 1
[0055] A method for fabricating a perovskite / crystalline silicon tandem solar cell, comprising:
[0056] (1) Preparation of HJT bottom cells:
[0057] The silicon wafer is texturized and cleaned (the initial polishing process uses ozone cleaning + initial polishing + ozone cleaning, followed by hydrofluoric acid cleaning, slow lifting and drying). After texturization and cleaning, plasma-enhanced chemical vapor deposition (PECVD) is performed to deposit amorphous silicon films on the front and back sides respectively. ITO thin films are deposited on the back side by PVD. Then, screen printing and low-temperature curing are performed sequentially to obtain the HJT bottom cell. The HJT bottom cell has a pyramid textured structure with an average height of 1.8 μm.
[0058] (2) Preparation of the ITO layer:
[0059] Cut the HJT bottom battery obtained in step (1) into 30mm×30mm specifications; use detergent water dispersion for ultrasonic treatment for 15min, rinse, then use deionized water for ultrasonic treatment for 15min, and isopropanol (IPA) for ultrasonic treatment for 15min; dry; spin-coat IPA (spin-coating speed 2000rpm, time 30s), and then UVO treatment for 15min.
[0060] The magnetron sputtering equipment was preheated to 130℃ until the vacuum degree was less than 9×10⁻⁶. -4 Pa; Water vapor is introduced into the vacuum chamber; the pressure of the water vapor is adjusted to 0.1 Pa by regulating the valve, and then a mixture of argon, oxygen and argon-hydrogen (volume ratio of 1:34:1:14) is introduced into the vacuum chamber, with the amount of the mixed gas containing water vapor being 200 sccm; using the HJT bottom cell as the substrate and indium tin oxide as the target, magnetron sputtering is performed to obtain an ITO layer with a thickness of 13 nm; the power is 0.4 kW, the sputtering rate is 4.8 mm / s, and the time is 20 min;
[0061] The sample obtained by magnetron sputtering was taken out and annealed at 100℃ for 10 min.
[0062] (3) Preparation of MeO-2PACz layer:
[0063] 0.3 mg MeO-2PACz was mixed with IPA to obtain a MeO-2PACz solution with a mass concentration of 0.3 mg / mL. This solution was then sprayed onto the surface of the ITO layer away from the HJT bottom cell to obtain a MeO-2PACz layer with a thickness of 3 nm.
[0064] (4) Layer preparation:
[0065] 4 respectively and 0.8 PbI₂ and CsBr were deposited at a high rate to obtain an inorganic phase framework. Then, an organic ammonium salt solution prepared from FAI and MAI (FAI:MAI = 16:1) was spin-coated onto the surface of the inorganic phase framework at 2000 rpm for 30 s. Annealing was then performed at 160℃ for 15 min in an environment with 30%–40% air humidity to obtain a thickness of 900 nm. Layer (denoted as PVK layer);
[0066] (5) Preparation of C60 layer:
[0067] A C60 layer was prepared by vapor deposition on one side of the perovskite surface at a deposition rate of 0.3 Å / s, resulting in a C60 layer with a thickness of 13 nm.
[0068] (6) Preparation of SnO2 layer:
[0069] SnO2 was deposited on one side of C60 using the ALD method at a deposition rate of 0.1 nm / cycle, resulting in a SnO2 layer with a thickness of 20 nm.
[0070] (7) Preparation of the IZO layer:
[0071] An IZO layer was magnetron sputtered onto one side of the SnO2 layer without the need for water vapor to be introduced during the magnetron sputtering process, resulting in an IZO layer with a thickness of 30 nm.
[0072] (8) Preparation of the Ag layer:
[0073] A 120nm thick Ag layer was obtained by screen printing on one side of the IZO layer.
[0074] The stacked structure of the perovskite / crystalline silicon tandem solar cell prepared in Example 1 is shown as follows:
[0075] Ag / ITO / Amorphous Silicon / Silicon / Amorphous Silicon / ITO / MeO-2PACz / PVK / C60 / SnO2 / IZO / Ag.
[0076] Example 2
[0077] The difference from Example 1 is that the gas flow rate in step (2) is 300 sccm. The remaining steps are the same as in Example 1.
[0078] Example 3
[0079] The difference from Example 1 is that the amount of mixed gas introduced in step (2) is 100 sccm. The remaining steps are the same as in Example 1.
[0080] Example 4
[0081] The difference from Example 1 is that in step (2), the pressure of the steam is adjusted to 1 Pa by adjusting the valve. The remaining steps are the same as in Example 1.
[0082] Example 5
[0083] The difference from Example 1 is that in step (2), the pressure of the steam is adjusted to 1.2 Pa by adjusting the valve. The remaining steps are the same as in Example 1.
[0084] Example 6
[0085] The difference from Example 1 is that in step (2), the magnetron sputtering temperature is 200°C, the power is 0.6kW, and the sputtering rate is 6mm / s. The remaining steps are the same as in Example 1.
[0086] Example 7
[0087] The difference from Example 1 is that in step (2), the magnetron sputtering power is 0.2kW and the sputtering rate is 3mm / s. The remaining steps are the same as in Example 1.
[0088] Example 8
[0089] The difference from Example 1 is that in step (2), the magnetron sputtering temperature is 220°C, the magnetron sputtering power is 0.7kW, and the sputtering rate is 6.4mm / s. The remaining steps are the same as in Example 1.
[0090] Comparative Example 1
[0091] The difference from Example 1 is that water vapor is not introduced in step (2), but only a mixture of argon, oxygen and argon-hydrogen is introduced. The remaining steps are the same as in Example 1.
[0092] The ITO layers prepared in step (2) of the above embodiments and comparative examples of this application were subjected to contact angle testing according to GB / T 30447-2013 "Method for Measurement of Contact Angle of Nanofilms". The test results are shown in Table 1. (The last sentence appears to be incomplete and possibly refers to a different topic.) 2 Under illumination, the perovskite / crystalline silicon tandem solar cells prepared in the above embodiments and comparative examples of this application were subjected to photoelectric performance tests and long-term stability tests. The test results are shown in Table 1.
[0093] The long-term stability test conditions include: continuous maximum power point tracking (MPPT) under standard light intensity (1 SUN), with a typical test duration of 1000 hours, simulating the percentage performance degradation of photoelectric conversion efficiency under long-term illumination. This test requires a nitrogen-protected or temperature-controlled environment to eliminate interference.
[0094] Table 1
[0095]
[0096] As can be seen from the above description, the embodiments of the present invention achieve the following technical effects:
[0097] In the preparation method of the first transparent oxide conductive layer 20 of this application, a mixed gas containing water vapor is introduced during the magnetron sputtering process, and the mixed gas is decomposed under the action of the plasma field to generate hydroxyl radicals (-OH). These hydroxyl radicals meet with the particles generated by the sputtering of the target material and undergo a chemical reaction to generate transparent oxide conductive material particles, which are deposited on one side surface of the crystalline silicon bottom cell 10. Then, the first transparent oxide conductive layer 20 is obtained by heat treatment.
[0098] Traditional magnetron sputtering methods for preparing the first transparent oxide conductive layer 20 typically require an inert atmosphere to avoid target oxidation and the introduction of impurities. However, this application introduces water vapor into the reaction, which can increase the hydroxyl content on the surface of the first transparent oxide conductive layer 20, improve its interfacial properties, thereby enhancing its bonding force with the self-assembled monolayer 30 (SAM layer) or the perovskite active material layer 40, inhibiting film shedding, and thus improving the long-term stability and photoelectric conversion efficiency of the perovskite / crystalline silicon tandem solar cell.
[0099] It should be noted that the terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such terms can be used interchangeably where appropriate so that the embodiments of this application described herein can be implemented, for example, in a sequence other than those described herein.
[0100] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.
Claims
1. A perovskite / crystalline silicon tandem solar cell, characterized in that, The perovskite / crystalline silicon tandem solar cell comprises a crystalline silicon base cell (10), a first transparent oxide conductive layer (20), an optional self-assembled monolayer (30), a perovskite active material layer (40), an electron transport layer (50), a buffer layer (60), a second transparent oxide conductive layer (70), and a metal electrode layer (80) stacked sequentially. The crystalline silicon base cell (10) has a pyramidal textured structure. The first transparent oxide conductive layer (20), the optional self-assembled monolayer (30), the perovskite active material layer (40), the electron transport layer (50), the buffer layer (60), and the second transparent oxide conductive layer (70) are all conformally fitted to the crystalline silicon base cell (10). The preparation method of the first transparent oxide conductive layer (20) includes: Using the crystalline silicon bottom cell (10) as the substrate, and one or more of indium tin oxide, zinc oxide and aluminum-doped zinc oxide as the target material, magnetron sputtering is performed in a mixed gas containing water vapor, and then the first transparent oxide conductive layer (20) is obtained after heat treatment.
2. The perovskite / crystalline silicon tandem solar cell according to claim 1, characterized in that, The flow rate of the mixed gas is 200–300 sccm; Preferably, the partial pressure of water vapor in the mixed gas is 0.1 to 1 Pa.
3. The perovskite / crystalline silicon tandem solar cell according to claim 1, characterized in that, The mixed gas is a mixture of water vapor, argon, oxygen and hydrogen; Preferably, the mixed gas is a mixture of water vapor, argon, oxygen and hydrogen in a volume ratio of 1:(31-34):1:(14-17).
4. The perovskite / crystalline silicon tandem solar cell according to any one of claims 1 to 3, characterized in that, The magnetron sputtering temperature is 130–200℃, the power is 0.2–0.6kW, the sputtering rate is 3–6mm / s, and the gas pressure is 10. -4 ~10 -5 Pa.
5. The perovskite / crystalline silicon tandem solar cell according to any one of claims 1 to 4, characterized in that, The thickness of the first transparent oxide conductive layer (20) is 10-20 nm.
6. The perovskite / crystalline silicon tandem solar cell according to claim 5, characterized in that, The heat treatment temperature is 110–160°C, and the time is 15–20 min.
7. The perovskite / crystalline silicon tandem solar cell according to claim 6, characterized in that, The perovskite / crystalline silicon tandem solar cell includes the self-assembled monolayer (30), the thickness of which is 3-5 nm. Preferably, the material of the self-assembled monolayer (30) is selected from one or more of (2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl)phosphoric acid, [4-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl)phosphoric acid and [4-(7H-dibenzocarbazole-7-yl)butyl]phosphoric acid.
8. The perovskite / crystalline silicon tandem solar cell according to claim 7, characterized in that, The self-assembled monolayer (30) is prepared by vapor deposition or spraying.
9. The perovskite / crystalline silicon tandem solar cell according to any one of claims 5 to 8, characterized in that, The crystalline silicon bottom cell (10) is selected from HJT bottom cells, TOPCon bottom cells, or ABC bottom cells; preferably, the average height of the pyramid textured structure in the crystalline silicon bottom cell (10) is 1.7 to 2.5 μm; Preferably, the thickness of the perovskite active material layer (40) is 700-900 nm, and the material is selected from materials formed by the hybridization of inorganic salt and organic salt; wherein, the inorganic salt is selected from PbI2 and / or CsBr, and the organic salt is selected from FAI and / or MAI; Preferably, the electron transport layer (50) has a thickness of 10–20 nm, and its material is selected from TiO2, PCBM, and C. 60 One or more of the following; Preferably, the thickness of the buffer layer (60) is 20-30 nm, and its material is selected from SnO2 and / or Al2O3; Preferably, the thickness of the second transparent oxide conductive layer (70) is 30-40 nm, and its material is selected from indium tin oxide or zinc oxide; Preferably, the thickness of the metal electrode layer (80) is selected from 120 to 150 nm, and its material is selected from one or more of Au, Ag, Cu and Al.
10. A method for preparing a perovskite / crystalline silicon tandem solar cell according to any one of claims 1 to 9, characterized in that, The preparation method includes: Step S1, prepare crystalline silicon bottom cell (10). Step S2, a first transparent oxide conductive layer (20), an optional self-assembled monolayer (30), a perovskite active material layer (40), an electron transport layer (50), a buffer layer (60), a second transparent oxide conductive layer (70), and a metal electrode layer (80) are sequentially prepared on one side surface of the crystalline silicon bottom cell (10); wherein, the preparation method of the first transparent oxide conductive layer (20) includes: Using the crystalline silicon bottom cell (10) as the substrate, and one or more of indium tin oxide, zinc oxide and aluminum-doped zinc oxide as the target material, magnetron sputtering is performed in a mixed gas containing water vapor, and the first transparent oxide conductive layer (20) is obtained after heat treatment.