Enhancing the Efficiency and Stability of Perovskite Solar Cells Using Chemical Bath Deposition of SnO2 Electron Transport Layers and 3D/2D Heterojunctions

Abstract Chemical bath deposition (CBD) is an effective technique used to produce high‐quality SnO2 electron transport layers (ETLs) employed in perovskite solar cells (PSCs). By optimizing the CBD process, high‐quality SnO2 films are obtained with minimal oxygen vacancies and close energy level alignment with the perovskite layer. In addition, the 3D perovskite layers are passivated with n‐butylammonium iodide (BAI), iso‐pentylammonium iodide (PNAI), or 2‐methoxyethylammonium iodide (MOAI) to form 3D/2D heterojunctions, resulting in defect passivation, suppressing ion migration and improving charge