Unveiling high-efficiency, stable lead-free 2D Dion-Jacobson/3D perovskite solar cells with minimized non-radiative losses

Abstract

This study introduces a novel design for FASnI₃ solar cells integrating a 2D Dion-Jacobson (DJ) layer as an interfacial layer to enhance performance. Using the Detailed Balance principle, photoluminescence quantum yield (PLQY) and quasi-Fermi level splitting (QFLS) were optimized. The study investigates the impact of varying the number of 2D DJ layers, revealing that while increasing the layers improves metrics like J_SC and V_OC, as well it increases series resistance., reducing the fill factor (FF). The 2D DJ layer's quantum confinement impact reduces the bandgap (Eg), enhancing charge generation and carrier dynamics, which boosts J_SC and V_OC. Additionally, the 2D DJ layer mitigates interface defects between the absorber and the ETL. The optimal configuration, a single 2D DJ layer with Ga₂O₃ as the ETL, achieved a PCE of 18.16 %, representing an 61.5 % improvement over conventional designs. This design balances efficiency, stability, and environmental sustainability, providing a capable solution for high-performance lead-free solar cells.