Evaluating the Potential of Lead‐Free Nontoxic Cs2BiAgI6‐Based Double Perovskite Solar Cell

Recently, the efficiency of single‐junction perovskite solar cells has been competing with the crystalline Si solar cells. However, the perovskite absorbers are toxic and susceptible to moisture. Herein, the performance of an environmentally benign and durable Cs 2 BiAgI 6 light harvester using the 1D Solar Cell Capacitance Simulator (SCAPS‐1D) software package is evaluated. The primary physical parameters, namely, defect and doping densities and thickness of the subsequent layers, are varied to achieve high efficiencies. The optimized Cs 2 BiAgI 6 ‐based double perovskite solar cells with three distinct hole‐transporting layers (HTLs) (i.e., MoO 3 , CuSCN, and spiro‐OMeTAD) deliver a power conversion efficiency of ≈29% with AZnO as electron transport layer (ETL). Further, a variety of possible rear electrodes are explored, and their effect on the performance is estimated. For real‐time examination of the Cs 2 BiAgI 6 ‐based double perovskite solar cells, the variation of power conversion efficiency (PCE) concerning the operating temperature is estimated. The thickness of the Cs 2 BiAgI 6 light harvester layer and the bulk defect density are the key aspects in attaining high power conversion efficiencies in Cs 2 BiAgI 6 ‐based double perovskite solar cells.