Solar cell and preparation method thereof
By inkjet printing on the substrate and combining it with multiple gas quenching processes, the problem of uneven coverage of perovskite films on textured silicon substrates was solved, realizing high-efficiency and stable perovskite/crystalline silicon tandem solar cells, and improving cell efficiency and stability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SHENZHEN PHENOSOLAR TECHNOLOGY CO LTD
- Filing Date
- 2026-02-02
- Publication Date
- 2026-05-15
AI Technical Summary
In the prior art, it is difficult to form a complete and high-quality perovskite film on a textured silicon substrate for perovskite/crystalline silicon tandem solar cells. This is mainly due to the insufficient wetting and spreading properties of perovskite ink on the textured silicon substrate surface, resulting in pinholes and discontinuous coverage. In addition, the crystallization is uneven during the conventional airflow-assisted crystallization process, which affects the cell efficiency and stability.
A perovskite wet film is formed on the substrate using inkjet printing technology, and then subjected to multiple gas quenching processes. This process combines low-pressure, high-flow and medium-pressure, low-flow gas flows to ensure uniform nucleation and crystallization on the raised surface. After annealing, a high-quality perovskite film is formed, reducing film stress and defects.
It achieves complete coverage of the perovskite film on the substrate, improves grain uniformity, enhances battery efficiency (greater than 25% efficiency in small areas and greater than 22% efficiency in large areas), reduces pinholes, and improves battery stability and industrialization potential.
Smart Images
Figure CN122054882A_ABST
Abstract
Description
Technical Field
[0001] This disclosure relates to the field of solar cells, and in particular to a solar cell and a method for its fabrication. Background Technology
[0002] The highest efficiency of crystalline silicon solar cells has approached the theoretical limit, and a feasible path to improve efficiency is through perovskite tandem layers. The efficiency of perovskite / crystalline silicon tandem cells has reached 34.6%, still some room to reach the theoretical limit of 44%. Most high-efficiency tandem cells in current technologies rely on planar silicon substrates, and forming a complete and high-quality perovskite thin film on a textured silicon substrate presents certain challenges. Summary of the Invention
[0003] This disclosure provides a solar cell and a method for its fabrication, which can optimize the nucleation and crystallization of the formed perovskite thin film to obtain a high-quality perovskite thin film.
[0004] A method for preparing a solar cell, comprising:
[0005] A substrate is provided, the surface of which has a plurality of protrusions;
[0006] The perovskite precursor ink is printed onto the substrate using an inkjet printing process to form a wet perovskite film covering the protrusions.
[0007] A perovskite wet film was obtained by treating it with a multiple gas quenching process;
[0008] The perovskite pre-crystallized film was annealed to obtain a perovskite film layer.
[0009] In the gas quenching process, the gas flow rate of the preceding gas quenching process is greater than that of the following gas quenching process, and the gas pressure of the preceding gas quenching process is less than that of the following gas quenching process.
[0010] In one embodiment, the incident angle of the gas in the preceding gas quenching process is smaller than the incident angle of the gas in the subsequent gas quenching process.
[0011] The incident angle is the angle between the gas jet and the surface of the substrate.
[0012] In one embodiment, when the surface of the perovskite wet film away from the substrate changes from a specular reflective state to a matte state, the perovskite wet film is treated with the multiple gas quenching process.
[0013] In one embodiment, the perovskite pre-crystallized film is annealed using a two-step annealing process to obtain the perovskite film layer.
[0014] In this process, the process temperature of the previous annealing process is lower than that of the subsequent annealing process, and the process time of the previous annealing process is shorter than that of the subsequent annealing process.
[0015] In one embodiment, before forming a perovskite wet film covering the protrusions on the substrate using perovskite precursor ink, the preparation method further includes:
[0016] An organic self-assembled monolayer is formed on the surface of the substrate having the protrusions;
[0017] The perovskite wet film is located on the surface of the organic self-assembled monolayer away from the substrate.
[0018] In one embodiment, forming an organic self-assembled monolayer on the surface of the substrate having the protrusions includes:
[0019] An organic self-assembled monolayer transition layer is formed on the surface of the substrate by spraying or dipping an organic self-assembled monolayer solution.
[0020] The organic self-assembled monolayer is annealed to form the organic self-assembled monolayer.
[0021] In one embodiment, an inkjet printing process is used to print perovskite precursor ink onto a substrate to form a wet perovskite film covering the protrusions, including:
[0022] Cs x DMA y MA z PbI3 material, carrier solvent, regulating additives and surfactants are mixed to obtain the perovskite precursor ink;
[0023] The perovskite precursor ink is printed onto the substrate using a printhead to form the perovskite wet film.
[0024] In one embodiment, prior to printing the perovskite precursor ink onto the substrate using a printhead to form the perovskite wet film, the method further includes:
[0025] The substrate is subjected to plasma treatment or ultraviolet ozone oxidation treatment; or
[0026] A buffered perovskite wet film is printed or spin-coated on the substrate; Cs in the buffered perovskite wet film x DMA y MA z Concentration of PbI3 material and Cs in perovskite wet film x DMA y MA zThe concentration ratio of PbI3 materials ranges from 0.1 to 0.3.
[0027] In one embodiment, the regulating additive includes at least one of halide salt crystallization regulating additives, surface activity regulating additives, and wetting regulating additives.
[0028] In one embodiment, an inkjet printing process is used to print perovskite precursor ink onto a substrate to form a wet perovskite film covering the protrusions, including:
[0029] A multi-layered perovskite wet film is formed on the substrate by using a multi-partition printing method.
[0030] The multiple partition printing corresponds to multiple layers of perovskite sub-wet films; the areal density of the perovskite sub-wet film printed in the first partition is less than the areal density of the perovskite sub-wet films printed in the other partitions; the ratio between the thickness of each perovskite sub-wet film and the thickness of the perovskite wet film includes 0.3-0.6.
[0031] A solar cell is manufactured using the preparation method described above.
[0032] In the aforementioned method for fabricating solar cells, a two-stage gas quenching process—first low-pressure, high-flow rate followed by medium-pressure, low-flow rate—ensures uniform nucleation and crystallization on the raised, rough surface. This results in more uniform grains in the perovskite film, reducing stress and defects. This improves the efficiency of the solar cell, achieving efficiencies greater than 25% for small areas and greater than 22% for large areas. Simultaneously, it achieves complete coverage of the perovskite film on the substrate, with no obvious pinholes within the film. Attached Figure Description
[0033] To more clearly illustrate the technical solutions in the embodiments or related technologies of this disclosure, the accompanying drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0034] Figure 1 This is a schematic flowchart of the method for preparing a solar cell in an embodiment of this application;
[0035] Figure 2 In this embodiment of the application, inkjet printing technology is used to print perovskite precursor ink onto the substrate;
[0036] Figure 3 This is a cross-sectional schematic diagram of a solar cell. Detailed Implementation
[0037] To facilitate understanding of the embodiments of this disclosure, a more complete description of the embodiments of this disclosure will be provided below with reference to the accompanying drawings. Preferred embodiments of the embodiments of this disclosure are shown in the drawings. However, the embodiments of this disclosure can be implemented in many different forms and are not limited to the embodiments described herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.
[0038] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which embodiments of this disclosure belong. The terminology used herein in the description of embodiments of this disclosure is for the purpose of describing particular embodiments only and is not intended to be limiting of the embodiments of this disclosure. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.
[0039] In the description of the embodiments of this disclosure, it should be understood that the terms "upper", "lower", "vertical", "horizontal", "inner", "outer", etc., indicate the orientation or positional relationship based on the method or positional relationship shown in the drawings. They are only for the convenience of describing the embodiments of this disclosure and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this disclosure.
[0040] In the description of this disclosure, "a plurality of" means at least two, such as two, three, etc., unless otherwise expressly and specifically defined. In the description of this disclosure, "several" means at least one, such as one, two, etc., unless otherwise expressly and specifically defined.
[0041] In related technologies, inkjet printing is used to deposit perovskite films on planar silicon substrates. Forming a complete and high-quality perovskite film on textured silicon substrates presents challenges. The main difficulties are: insufficient wetting and spreading of perovskite ink on the textured silicon substrate surface, leading to pinholes, discontinuous coverage, and unfilled valleys; and excessively rapid local evaporation during conventional airflow-assisted crystallization, resulting in uneven surface crystallization, reduced overall battery efficiency and stability, and hindering industrialization. Developing a method capable of depositing dense perovskite films on textured silicon substrates while being compatible with large-area inkjet printing is an urgent problem to be solved.
[0042] To address the aforementioned problems, this disclosure provides a method for fabricating a solar cell. Figure 1 This is a schematic flowchart illustrating the method for fabricating solar cells in an embodiment of this application. See also... Figure 1 A method for preparing a solar cell, comprising:
[0043] S102, providing a substrate, the surface of which has a plurality of protrusions.
[0044] As an example, a substrate is provided, the surface of which has multiple protrusions. For example, the substrate is a textured silicon substrate cell of SHJ (Silicon Heterojunction) or TopCon (Tunnel Oxide Passivated Contact). For example, the textured silicon substrate cell completes the back electrode or completes the back passivation on the surface away from the protrusions.
[0045] For example, a transparent conductive oxide layer is sputtered onto a surface of a substrate having raised areas, serving as a composite interface. As an example, the materials of the transparent conductive oxide layer include indium tin oxide and indium zinc oxide.
[0046] S104 uses inkjet printing technology to print perovskite precursor ink onto a substrate, forming a wet perovskite film covering the raised areas.
[0047] As an example, an inkjet printing process is used to print perovskite precursor ink onto a substrate to form a perovskite wet film covering the protrusions; wherein the perovskite wet film is located on the side of the substrate with the protrusions.
[0048] S106, perovskite wet film is treated with multiple gas quenching processes to obtain perovskite pre-crystallized film.
[0049] As an example, a perovskite wet film is processed by multiple gas quenching processes to obtain a perovskite pre-crystallized film; wherein, according to the sequence of the gas quenching processes, the gas flow rate of the previous gas quenching process is greater than the gas flow rate of the subsequent gas quenching process, and the gas pressure of the previous gas quenching process is less than the gas pressure of the subsequent gas quenching process.
[0050] For example, a two-stage gas quenching process is used to treat the perovskite wet film. The gas flow rate in the first gas quenching process is greater than that in the second gas quenching process, and the gas pressure in the first gas quenching process is less than that in the second gas quenching process. As an example, the gases used in the gas quenching process include nitrogen and dry air, and the nozzle diameter for the gas quenching process includes 2mm-5mm, such as 2mm, 3mm, 4mm, 5mm, etc.
[0051] As an example, the gas pressure in the first gas quenching process includes 0.05 Pa to 0.2 Pa, such as 0.05 Pa, 0.07 Pa, 0.09 Pa, 0.1 Pa, 0.15 Pa, 0.2 Pa, etc.; the blowing time in the first gas quenching process includes 10 s to 30 s, such as 10 s, 15 s, 17 s, 20 s, 23 s, 25 s, 27 s, 30 s, etc.; the gas volumetric flow rate in the first gas quenching process includes 20 L / min to 60 L / min, such as 20 L / min, 30 L / min, 40 L / min, 50 L / min, 55 L / min, 60 L / min, etc. Through the first gas quenching process, most of the solvent in the perovskite wet film can be quickly removed.
[0052] As an example, the gas pressure in the second gas quenching process includes 0.1Pa-0.3Pa, such as 0.1Pa, 0.15Pa, 0.17Pa, 0.19Pa, 0.20Pa, 0.25Pa, 0.3Pa, etc.; the blowing time in the second gas quenching process includes 10s-20s, such as 10s, 13s, 15s, 17s, 19s, 20s, etc.; the gas volumetric flow rate in the second gas quenching process includes 5L / min-20L / min, such as 5L / min, 7L / min, 9L / min, 10L / min, 15L / min, 20L / min, etc. Uniform nucleation is achieved through the second gas quenching process.
[0053] S108 is used to anneal the perovskite pre-crystallized film to obtain the perovskite film layer.
[0054] In the aforementioned method for fabricating solar cells, a two-stage gas quenching process—first low-pressure, high-flow rate followed by medium-pressure, low-flow rate—ensures uniform nucleation and crystallization on the raised, rough surface. This results in more uniform grains in the perovskite film, reducing stress and defects. This improves the efficiency of the solar cell, achieving efficiencies greater than 25% for small areas and greater than 22% for large areas. Simultaneously, it achieves complete coverage of the perovskite film on the substrate, with no obvious pinholes within the film.
[0055] As an example, before using inkjet printing to print perovskite precursor ink onto a substrate to form a wet perovskite film covering the protrusions, the fabrication method of the solar cell also includes: depositing on the surface of the substrate with protrusions using a magnetron sputtering process. Layer; among which, The layer thickness ranges from 20nm to 40nm, for example, 20nm, 25nm, 30nm, 35nm, 40nm, etc. For example, The layer serves as a hole transport / wetting layer in perovskite / crystalline silicon tandem solar cells. It can be understood that this layer forms... After the layer, in an air or oxygen atmosphere, for The layers are heat-treated at 150℃ for 5-10 minutes to improve their work function and density.
[0056] In one embodiment, before forming a perovskite wet film covering the protrusions on a substrate using a perovskite precursor ink, the preparation method further includes: forming an organic self-assembled monolayer on the surface of the substrate having the protrusions; wherein the perovskite wet film is located on the surface of the organic self-assembled monolayer away from the substrate. The organic self-assembled monolayer has a wetting / interface regulation function, which can improve the wettability of the valley regions and enhance the coverage of the subsequently formed perovskite film layer in the valley regions.
[0057] As an example, the thickness of organic self-assembled monolayers ranges from 1 nm to 3 nm. Exemplary materials for organic self-assembled monolayers include 2PACz, Me-4PACz, MeO-2PACz, Br-2PACz (carbazole-phosphate derivatives); PTAA-PA (phosphorylated PTAA oligomers), 4PADCB-PA, and other phosphate-anchored molecules; benzoic acid / carboxylic acid-anchored SAMs, such as 4-aminobenzoic acid derivatives; and other substitutes for the thiophene / carbazole / triphenylamine backbone and phosphate-anchored groups. These organic self-assembled monolayers are connected to the phosphate / carboxylic acid groups... Covalent or strong coordination adsorption forms on the surface, achieving consistent wetting and energy level regulation with peaks and valleys.
[0058] In one embodiment, forming an organic self-assembled monolayer on the surface of the substrate having the protrusion includes: forming an organic self-assembled monolayer transition layer on the surface of the substrate by spraying or dipping an organic self-assembled monolayer solution; and annealing the organic self-assembled monolayer transition layer to form the organic self-assembled monolayer.
[0059] As an example, an organic self-assembled monolayer solution of 0.5–2 mg / mL is prepared; wherein the solvent in the organic self-assembled monolayer solution includes at least one of IPA, ethanol, and chlorobenzene. Exemplarily, the solvent is IPA.
[0060] The substrate can be heated to 40℃-50℃, and an organic self-assembled monolayer solution can be sprayed onto the substrate to form an organic self-assembled monolayer transition layer on the substrate surface. The number of spraying times of the organic self-assembled monolayer solution includes 1 to 3 times. When the number of spraying times is greater than 1, the time interval between two spraying times is 10 seconds.
[0061] Alternatively, the substrate can be immersed in an organic self-assembled monolayer solution at room temperature for a preset time, and then removed to form an organic self-assembled monolayer transition layer on the substrate surface by dip coating; wherein the immersion time includes 5 min-15 min.
[0062] As an example, the substrate forming the organic self-assembled monomolecular transition layer is baked at a temperature of 90℃–100℃ for 2 min–5 min to remove residual solvent in the organic self-assembled monomolecular transition layer, forming an organic self-assembled monomolecular layer of 1 nm–3 nm.
[0063] Figure 2 This is a schematic diagram illustrating the process of using inkjet printing to print perovskite precursor ink onto a substrate to form a wet perovskite film covering the raised areas, as described in this embodiment of the application. (See attached diagram.) Figure 2 In one embodiment, an inkjet printing process is used to print perovskite precursor ink onto a substrate to form a wet perovskite film covering the protrusions, comprising:
[0064] S202, Cs x DMA y MA z The perovskite precursor ink is obtained by mixing PbI3 material, carrier solvent, regulating additives and surfactants.
[0065] As an example, the Cs of the perovskite component x DMA y MA z The perovskite precursor ink is obtained by mixing PbI3 material, carrier solvent, regulating additives, and surfactants; wherein x+y+z=1. By regulating the additives and surfactants, the wettability and flowability of the perovskite precursor ink can be improved.
[0066] As an example, Cs x DMA y MA z In PbI3 materials, x includes 0.2-0.35, such as 0.2, 0.25, 0.27, 0.29, 0.3, 0.32, 0.35, etc.; y includes 0.1-0.3, such as 0.1, 0.15, 0.17, 0.19, 0.2, 0.25, 0.3, etc.; z includes 0.4-0.6, such as 0.4, 0.45, 0.47, 0.49, 0.5, 0.55, 0.57, 0.6, etc.
[0067] As an example, the support solvent includes a mixture of DMF (dimethylformamide) and DMSO (dimethyl sulfoxide); wherein the volume ratio of DMF to DMSO includes 3:1–6:1, such as 3:1, 4:1, 5:1, 6:1, etc. The support solvent can also be selected from a highly polar, strong Lewis base coordination solvent / co-coordination solvent system, such as GBL or NMP.
[0068] In one embodiment, the regulating additive includes at least one of halide salt crystallization regulating additives, surface activity regulating additives, and wetting regulating additives. Exemplary examples include halide salt crystallization regulating additives such as MACl, RbI, KCl, and FACl, with a MACl molar ratio ranging from 10% to 30%, for example, 10%, 15%, 20%, 25%, or 30%. Surface activity regulating additives include F-127 and the Tween series, with a concentration ranging from 0.01 wt% to 0.1 wt%, such as 0.01 wt%, 0.03 wt%, 0.05 wt%, 0.07 wt%, 0.09 wt%, or 0.1 wt%. Wetting regulating additives include the Triton series. By using surface activity regulating additives and wetting regulating additives, crystallization kinetics can be controlled, surface tension reduced, and surface wetting improved.
[0069] S204, the perovskite precursor ink is printed onto the substrate using a printhead to form the perovskite wet film.
[0070] It is understood that, before the perovskite precursor ink is sprayed onto the substrate using a printhead to form the perovskite wet film, the method for fabricating the solar cell further includes: placing the substrate on a pinhole hot stage or a nitrogen glove box hot stage, preheating it to 35℃-55℃, and maintaining it for 3min-5min to ensure uniform substrate surface temperature. As an example, the ambient temperature for substrate preheating is controlled at 20℃-30℃, and the ambient humidity is controlled at 25-40%RH; or a nitrogen atmosphere. <1 ppm. As an example, the time interval between the formation of the organic self-assembled monolayer and the preheated substrate is less than or equal to 30 min.
[0071] As an example, the perovskite precursor ink is printed onto the substrate using a piezoelectric printhead. Exemplarily, the piezoelectric printhead has a print volume of 10 pL–35 pL and an orifice diameter of 20 μm–30 μm.
[0072] It is understood that before the perovskite precursor ink is printed onto the substrate using a printhead to form the perovskite wet film, the prepared perovskite precursor ink is filtered through a 0.22 μm PTFE filter membrane and placed in a constant-temperature ink bath at 25°C for 10–20 minutes to degas. The printhead is calibrated using an ejection waveform and drop watcher to ensure that satellite droplets are less than 5%. For example, the ejection waveform includes waveform width and waveform amplitude.
[0073] In one embodiment, before the perovskite precursor ink is sprayed onto the substrate using a printhead to form the perovskite wet film, the process further includes: subjecting the substrate to plasma treatment or ultraviolet ozone oxidation treatment to improve valley wetting and initial spreading. As an example, the plasma treatment or ultraviolet ozone oxidation treatment time includes 30-60 seconds.
[0074] In another embodiment, before the perovskite precursor ink is sprayed onto the substrate using a printhead to form the perovskite wet film, the method further includes: printing or spin-coating a buffer perovskite wet film onto the substrate; the buffer perovskite wet film contains Cs x DMA y MA z Concentration of PbI3 material and Cs in perovskite wet film x DMA y MA z The concentration ratio of PbI3 materials ranges from 0.1 to 0.3. It can be understood that Cs in the buffer perovskite wet film... x DMA y MA z Concentration of PbI3 material and Cs in perovskite wet film x DMA y MA z The concentration ratio of PbI3 material is 0.1-0.3, for example, 0.1, 0.2, 0.3, etc.
[0075] In one embodiment, an inkjet printing process is used to print perovskite precursor ink onto a substrate to form a perovskite wet film covering the protrusion. This includes: forming multiple layers of perovskite sub-wet films on the substrate using a multi-partition printing method; wherein each multi-partition printing corresponds to a multi-layer perovskite sub-wet film; the areal density of the perovskite sub-wet film printed in the first partition is less than the areal density of the perovskite sub-wet films printed in the remaining partitions; the ratio between the thickness of each perovskite sub-wet film and the thickness of the perovskite wet film includes 0.3-0.6.
[0076] It is understandable that a single partition printing process forms a perovskite sub-wet film covering the protrusions. As an example, the thickness of the perovskite sub-wet film is 30%-60% of the thickness of the perovskite wet film, such as 30%, 40%, 45%, 50%, 60%, etc.
[0077] As an example, the areal density of the perovskite sub-wet film printed in the first partition is 30%-40%, enabling rapid underlayment of the perovskite precursor ink and preferential filling of the valleys; the areal density of the perovskite sub-wet film printed in subsequent partitions increases to 60%-100%, thereby filling the peak areas. For example, after each partition printing of one layer of perovskite sub-wet film, it is allowed to stand for 3-8 seconds to allow the perovskite precursor ink to naturally flow back and self-level within the convex and trough (textured valleys).
[0078] After the final partition printing of the perovskite sub-wet film, the substrate temperature is maintained at 40℃–60℃ and left to stand for 10s–20s to allow the solvent in the perovskite sub-wet film to evaporate, and the perovskite sub-wet film reaches a “semi-wet film” state. Then, the perovskite wet film is subjected to an air quenching process to achieve in-situ slight solvent evaporation.
[0079] In one embodiment, when the surface of the perovskite wet film away from the substrate changes from a specular reflective state to a matte state, the perovskite wet film is treated with the aforementioned multiple air quenching process. As an example, after the perovskite wet film is left to stand for 10-20 seconds, the surface of the perovskite wet film away from the substrate changes from a specular reflective state to a matte state.
[0080] In one embodiment, the incident angle of the gas in the preceding gas quenching process is smaller than the incident angle of the gas in the subsequent gas quenching process; wherein, the incident angle is the angle between the gas jet line and the surface of the substrate.
[0081] As an example, the perovskite wet film is treated with a two-stage gas quenching process. The first gas quenching process can quickly remove the solvent and induce overall nucleation, while the second gas quenching process can achieve uniform nucleation and mild growth of the perovskite pre-crystallized film.
[0082] As an example, in the first gas quenching process, the distance between the nozzle and the surface of the perovskite wet film includes 20mm–40mm, and the incident angle of the gas includes 15°–30°. Through the first gas quenching process, the solvent on the surface of the perovskite wet film can be removed and the valley area can be simultaneously supersaturated, avoiding the peak from crystallizing first.
[0083] The time interval between the second gas quenching process and the first gas quenching process is less than or equal to 2 seconds. In the second gas quenching process, the distance between the nozzle and the surface of the perovskite wet film is 30 mm–50 mm, and the incident angle of the gas is 45°–70°. Through the second gas quenching process, the localized excessively rapid evaporation of the perovskite wet film can be suppressed, so that the nucleus density at the peaks and valleys of the textured surface is consistent, and the grains grow uniformly.
[0084] In one embodiment, a two-step annealing process is used to anneal the perovskite pre-crystallized film to obtain the perovskite film layer; wherein the process temperature of the first annealing process is lower than that of the second annealing process, and the process time of the first annealing process is shorter than that of the second annealing process. This two-step annealing process can further reduce the stress and pinholes in the perovskite film layer.
[0085] As an example, a substrate with a pre-crystallized perovskite film is transferred to a hot stage and annealed at 90 °C–120 °C for 10–20 min to form a dense black-phase perovskite film. Further, a two-step annealing process is used to anneal the pre-crystallized perovskite film: the first annealing process is performed at 90 °C for 5 min, and the second annealing process is performed at 110 °C for 10 min.
[0086] As an example, the thickness of the perovskite film ranges from 0.8 μm to 1.2 μm.
[0087] Figure 3 See the schematic cross-sectional view of the solar cell. Figure 3 The method for fabricating solar cells also includes: forming an electron transport layer on the surface of the perovskite film away from the substrate. As an example, using... (15nm–30 nm, thermal evaporation) and LiF (0.8nm–1.5 nm), or (10nm–30 nm, ALD / solution) to form an electron transport layer.
[0088] For example, the method for fabricating a solar cell further includes: forming a top transparent conductive layer and metal grid lines on the side of the electron transport layer away from the substrate, for example, forming a top transparent conductive layer of 80nm–150nm by sputtering IZO / ITO; forming silver grid lines by evaporation or screen printing, with a grid line thickness of 5μm–15μm.
[0089] As an example, methods for fabricating solar cells also include: depositing a thickness of 80 nm–120 nm. As an anti-reflection layer.
[0090] As an example, methods for fabricating solar cells also include: using UV adhesive / hot melt adhesive and glass / composite film encapsulation; edge sealing width of 2mm–5mm, and water-oxygen barrier layer WVTR < .
[0091] In this embodiment, the stability of the solar cell is improved, and it still maintains 90% of its initial efficiency after 200 cycles under −40-80℃ / 85%RH conditions.
[0092] It should be understood that, although Figures 1-2 The steps in the flowchart are shown sequentially as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order in which these steps are executed, and they can be performed in other orders. Figures 1-2 At least some of the steps in the process may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least some of the sub-steps or stages of other steps.
[0093] This disclosure also provides a solar cell manufactured using the solar cell fabrication method described in any of the preceding claims.
[0094] This disclosure also provides a photovoltaic module comprising a plurality of solar cells as described above, and / or solar cells manufactured using the method described in any of the above-described solar cell preparation methods.
[0095] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0096] The above-described embodiments are merely illustrative of several implementation methods of the present disclosure, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present disclosure embodiments, and these modifications and improvements all fall within the protection scope of the present disclosure embodiments.
Claims
1. A method for preparing a solar cell, characterized in that, include: A substrate is provided, the surface of which has a plurality of protrusions; The perovskite precursor ink is printed onto the substrate using an inkjet printing process to form a wet perovskite film covering the protrusions. A perovskite wet film was obtained by treating it with a multiple gas quenching process; The perovskite pre-crystallized film was annealed to obtain a perovskite film layer. In the gas quenching process, the gas flow rate of the preceding gas quenching process is greater than that of the following gas quenching process, and the gas pressure of the preceding gas quenching process is less than that of the following gas quenching process.
2. The preparation method according to claim 1, characterized in that, The incident angle of the gas in the previous gas quenching process is smaller than the incident angle of the gas in the subsequent gas quenching process. The incident angle is the angle between the gas jet and the surface of the substrate.
3. The preparation method according to claim 1, characterized in that, When the surface of the perovskite wet film away from the substrate changes from a specular reflective state to a matte state, the perovskite wet film is treated with the aforementioned multiple gas quenching process.
4. The preparation method according to claim 1, characterized in that, The perovskite pre-crystallized film was annealed using a two-step annealing process to obtain the perovskite film layer; In this process, the process temperature of the previous annealing process is lower than that of the subsequent annealing process, and the process time of the previous annealing process is shorter than that of the subsequent annealing process.
5. The preparation method according to claim 1, characterized in that, Before forming a perovskite wet film covering the protrusions on the substrate using perovskite precursor ink, the preparation method further includes: An organic self-assembled monolayer is formed on the surface of the substrate having the protrusions; The perovskite wet film is located on the surface of the organic self-assembled monolayer away from the substrate.
6. The preparation method according to claim 5, characterized in that, The formation of an organic self-assembled monolayer on the surface of the substrate having the protrusions includes: An organic self-assembled monolayer transition layer is formed on the surface of the substrate by spraying or dipping an organic self-assembled monolayer solution. The organic self-assembled monolayer is annealed to form the organic self-assembled monolayer.
7. The preparation method according to claim 1, characterized in that, The perovskite precursor ink is printed onto a substrate using an inkjet printing process to form a wet perovskite film covering the protrusions, comprising: Cs x DMA y MA z PbI3 material, carrier solvent, regulating additives and surfactants are mixed to obtain the perovskite precursor ink; The perovskite precursor ink is printed onto the substrate using a printhead to form the perovskite wet film.
8. The preparation method according to claim 7, characterized in that, Before the perovskite precursor ink is sprayed onto the substrate using a printhead to form the perovskite wet film, the process further includes: The substrate is subjected to plasma treatment or ultraviolet ozone oxidation treatment; or A buffered perovskite wet film is printed or spin-coated on the substrate; Cs in the buffered perovskite wet film x DMA y MA z Concentration of PbI3 material and Cs in perovskite wet film x DMA y MA z The concentration ratio of PbI3 materials ranges from 0.1 to 0.
3.
9. The preparation method according to claim 8, characterized in that, The regulating additives include at least one of halide salt crystallization regulating additives, surface activity regulating additives, and wetting regulating additives.
10. The preparation method according to claim 1, characterized in that, The perovskite precursor ink is printed onto a substrate using an inkjet printing process to form a wet perovskite film covering the protrusions, comprising: A multi-layered perovskite wet film is formed on the substrate by using a multi-partition printing method. The multiple partition printing corresponds to multiple layers of perovskite sub-wet films; the areal density of the perovskite sub-wet film printed in the first partition is less than the areal density of the perovskite sub-wet films printed in the other partitions; the ratio between the thickness of each perovskite sub-wet film and the thickness of the perovskite wet film includes 0.3-0.
6.
11. A solar cell, characterized in that, It is prepared by the preparation method described in any one of claims 1-10.