The Study On All-inorganic Perovskite Solar Cells Which Based On CsPbBr₃

Perovskite photovoltaic cells are derived from dye-sensitized cells.The core layer of the cell is the metal halide light absorption layer represented by ch3nh3pbi3.This kind of light absorption layer has a typical perovskite crystal structure,so it is named perovskite solar cells.Because of its low cost of raw materials,simple preparation equipment,simple process and rapid improvement of photoelectric conversion efficiency,it has been widely concerned by researchers in recent years.At present,the internationally certified photoelectric conversion efficiency of the battery has increased to 25.2%,so it is a new type of photovoltaic device.However,due to the existence of organic components in the absorption layer,the thermal stability of the material is not good,it is easy to deteriorate in the humid environment,and the performance life of the constructed battery is short,which is not suitable for industrial application.By using inorganic elements Cs⁺instead of organic elements in perovskite materials,the halogen bromine was selected to form CsPbBr₃ as absorption layer.The absorption layer has excellent thermal stability,humidity stability,light stability and structural stability,which provides an effective way to solve the material stability and extend the battery life.In this paper,two-step method was used to prepare high-quality perovskite CsPbBr₃ optical absorption layer,and the effect of antisolvent acetonitrile on the microstructure and morphology of CsPbBr₃ film was studied by introducing antisolvent acetonitrile to improve the performance of the optical absorption layer.The low-cost carbon was chosen as the back electrode material to form the ohmic contact,which formed the all inorganic perovskite battery based on CsPbBr₃ light absorption layer.The results show that the open circuit voltage,short circuit current and filling factor of the all inorganic perovskite solar cell with the addition of anti-solvent acetonitrile are significantly improved,and the photoelectric conversion efficiency is significantly improved by about 10%compared with the cell without anti solvent.In addition,the effect of different annealing temperature on the optical absorption layer of CsPbBr₃perovskite was also studied.The results show that when the annealing temperature is400?,the prepared CsPbBr₃ film has the best crystallinity,film quality,grain size and other aspects.The best performance and the highest efficiency of the solar cell constructed at this temperature is due to the reduction of the internal grain boundaries,the decrease of the recombination rate of photo generated carriers and the improvement of the photoelectric conversion efficiency of the solar cell.These studies provide a basis for further improving the efficiency and stability of all inorganic perovskite solar cells.