Design and optimization of Cs2AgInBr6/CsSnI3-based dual-absorber inorganic perovskite solar cell for enhanced broadband absorption

This article introduces an innovative dual-absorber solar cell design using Dicesium Silver Indium Hexabromide (Cs₂AgInBr₆) and Cesium Tin Tri-iodide (CsSnI₃) in a FTO/ZnO/Cs₂AgInBr₆/CsSnI₃/CFTS heterojunction architecture. The optimal energy band alignment, along with structural and electrical parameter optimization of the Cs₂AgInBr₆/CsSnI₃ dual-absorber configuration, enhances power conversion efficiency (PCE), overcoming limitations in single-absorber Cs₂AgInBr₆ perovskite photovoltaic cells (PPCs). This enhancement is due to the synergistic effects between absorbers, improving light absorption and charge carrier dynamics. Using SCAPS-1D, critical parameters such as absorber thickness, defect density, and carrier transport layers were optimized. The dual-absorber achieved a PCE of 25.32 %, V_oc of 0.95 V, fill factor of 86 %, and J_sc of 31.9 mA/cm², outperforming the 11.96 % PCE of single-absorber PPCs. A peak quantum efficiency (QE) of 90 % spanning over 300–1000 nm wavelength range was also obtained, surpassing the 79 % QE of single absorbers over 300–830 nm.