Increasing the Performance of Mixed Cation Mixed Halide Lead Based Perovskite Solar Cell by Passivating the Rare Interface: A SCAPS-1D Numerical Simulation Investigation

Thermal and photo instabilities are two major issues for organic-inorganic lead halide perovskite solar cells. Mixing of A site cations and X cite halogens are tried to address these issues, but the performance is still not reached the theoretical Shockley Quissier limit. One of the reasons for this is the energy loss ratio with band gap energy. Despite the high open circuit voltage, this ratio is lower for perovskite solar cell in competition with silicon technology. Open circuit voltage can be increased by different ways, but short circuit current is compromised. To increase open circuit voltage without affecting the short circuit current is the surface passivation technique. Numerous studies have been conducted on electron transport layer and perovskite interface, with a very few on hole transport layer and perovskite interface. Both interfaces are equally important. Here we passivated the later interface by inserting a 10 nm thick layer of caesium-formamide based lead mixed halide perovskite in FAMA mixed perovskite solar cell. Our proposed model achieved an efficiency of 31.42 % with a high fill factor of 86.4 %. At the same time, we recorded higher open circuit voltage of 1.46 V and 25.49 mA/cm 2 short circuit current. Our proposed model will help in experimental work for making highly efficient perovskite solar cells.