Numerical assessment and optimization of highly efficient lead-free hybrid double perovskite solar cell

In this work, a performance assessment of a double perovskite Cs2BiCuI6 solar cell with the typical lead-based perovskite CH3NH3PbI3 as an active layer is presented using SCAPS-1D software. The theoretical analysis depicts the improvement in power conversion efficiency (PCE) for Cs2BiCuI6-based solar cells. This shows that in the coming future, the hybrid double perovskite Cs2BiCuI6 possess the capability to replace toxic CH3NH3PbI3based solar cell which would help to create lead-free harmless solar cells. Detailed structural parameters optimization such as the absorbing layer thickness, and charge carrier mobility, and variation in interface defect density is carried out to enhance the device efficiency. This gives a PCE of 24.84 % for a hybrid double perovskite-based solar cell. The optimized values are 1013 cm-3, and 5 cm2 V-1 s-1 for interface defect density and carrier mobility respectively which also enhances the fill factor to 82 % with open circuit voltage of 1.28 V and 24.54 mA/cm2 short circuit current density Jsc.