Study On Preparation Process And Performance Of Large-area Perovskite Solar Cells And Modules

As of 2020,the photovoltaic conversion efficiency（PCE）of organic-inorganic hybrid perovskite solar cells（PSCs）has reached 25.5%,becoming the most promising photovoltaic technology.However,there are still many problems need to be solved urgently before commercial application,such as stability optimization,large-area preparation,and module structure design.Therefore,we will research on the stability optimization of electron transport layer（ETL）,the analysis of large-area PSCs and the design of the module structure.The main research contents and results are as follows:（1）Preparation of the high-performance ETL based on the low-temperature spin coating method.Firstly,we deposited SnO₂ by spin-coating colloid,and adjusted the speed to prepare ETL with different morphologies.Finally,the device based on 5000 r/s achieved a PCE of20.67%.Then,different concentrations of KCl were doped to passivate the SnO₂/perovskite interface.Finally,at a doping concentration of 3 mg/ml,the device achieved a PCE of 22.63%.Through surface morphology analysis,we found that as the spin-coating speed and doping concentration become higher,the film of SnO₂ will become more uniform.We compared the light and humidity stability of devices based on Ti O₂ and SnO₂,and found that the stability of SnO₂-doped devices far exceeds that of Ti O₂.Finally,we prepared a large-area PSCs with an active area of 1×1 cm²,and achieved a PCE of 17.83%.The uniformity of each functional layer was characterized by electroluminescence.（2）Research on the effect of module structure on the performance of perovskite series modules.Firstly,a module structure with 3 and 4 sub-cells in series was designed on a 4×4 cm² FTO.The final device achieved16.54%and 19.44%PCE on the effective area of 12.027 cm² and 11.628cm².Secondly,a perovskite module with 7 sub-cells connected in series was prepared on a 6.5×6.5 cm²FTO,and finally a PCE of 17.76%was achieved on an effective area of 28.56 cm².We found that as the area or number of sub-cells increases,the series resistance of the modules will also increase significantly,which affects the power output of the device.（3）Prepare and optimize the perovskite parallel module based on the new structure.On the FTO of 6×6 cm²,a module structure with two horizontal sub-cells connected in series and vertical six sub-cells connected in parallel is designed.In the end,18.43%of PCE was achieved on the active area of 13.5 cm².By further optimizing the component structure,18.82%of PCE was achieved on the active area of 21.06%,and the geometric fill factor（GFF）was increased from 60%to 79%.