Optimization of Electron Transport Layers for High Performance Perovskite Solar Cells

This work reports the impact of electron transport layers (ETLs) on the performance of perovskite solar cells (PSCs). The ETLs are based on tin (IV) oxide (SnO 2 ) prepared in different nanostructures. The carrier transport properties of PSCs are systematically characterized and the underlying mechanism for the enhancement in performance of PSCs is found. The strategies for optimizing the interface between the ETL and perovskite are demonstrated, yielding a champion device with a power conversion efficiency (PCE) of 20.8 %.