Research On Preparation Process Optimization And Application Of All-inorganic CsPbBr₃ Perovskite Solar Cells

In recent years,organic-inorganic hybrid perovskite solar cells have become a research hotspot in the photovoltaic field because of their excellent power conversion efficiency.However,this hybrid perovskite material’s intrinsic instability and the harsh preparation environment limit its further commercial application.All-inorganic Cs Pb Br₃perovskite materials have attracted much attention because of their good stability,low cost and can be prepared in an atmospheric environment,showing great application potential.The controllable preparation and growth kinetics of Cs Pb Br₃materials need to be further studied,and the conversion efficiency of photovoltaic devices is still low.Considering the instability caused by traditional organic hole transport materials and their high preparation cost,this master dissertation focuses on systematically studies of Cs Pb Br₃all-inorganic perovskite cells without a hole transport layer as the research object.Growth kinetics materials of Cs Pb Br₃was directive by adding2-phenylethylamine bromide to precursor solution.The crystallization and bandgap of Cs Pb Br₃perovskite film quality are the key process path to improve the perovskite solar cells’efficiency.Application in the solar cell without hole transmission layer.The main research contents and results are as follows:（1）Based on multi-step spin-coating preparation of Cs Pb Br₃perovskite films.Study on the perovskite cell preparation method and the critical process parameters include the spin-coating Pb Br₂,amount and number of spin-coating of Cs Br and substrate preheating temperature are optimized.The optimization tests show that the optimum spin-coating of Cs Br is five times and the spin-coating Pb Br₂in the atmospheric environment.The optimal preheating temperature of the substrate is 80℃.The perovskite films prepared under this condition are compact with a continuous high phase purity and good crystallization performance.The power conversion efficiency of the corresponding solar cells is increased from 3.6%to 4.7%without optimization.（2）Explore the synergy of temperature and additives.The First adoption of Pb Br₂in DMF and the addition of 2-phenylethylamine bromide（PEABr）solution to regulate the Cs Pb Br₃crystalline quality of the film.Effects of PEABr on the perovskite crystallization process and device performance are systematically investigated.The results show that the introduction of PEABr can effectively optimize Cs Pb Br₃.The crystalline properties of the two-dimensional perovskite materials can improve the grain boundaries and improve their transport properties.The prepared perovskite solar cells under the condition of annealing temperature of 100℃and adding 100μl of PEABr to 1ml precursor solution shows the highest power conversion efficiency of 8.25%,which is 57%higher than that of the device without PEABr.（3）Exploration fabricate all-inorganic solar perovskite solar cells hole-free transport layer FTO/Ti O₂/Cs Pb Br₃/Mo O₃/ITO.Adopting Cs Pb Br₃vaporizing a 10 nm thick Mo O₃on the perovskite layer,the auxiliary layer increases the device’s open-circuit voltage by 140%.By optimizing the conditions of ITO sputtering,a semi-transparent Cs Pb Br₃perovskite cell with no hole transport layer with an average transmittance of 40.3%in the visible light band from 380nm to 800 nm and a photoelectric conversion efficiency of 2.23%was initially obtained.It provides a new direction and idea for the research and design of all-inorganic solar perovskite solar cells in the future.