2D Ag-ZIF interlayer induces less carrier recombination for efficient and UV stable perovskite photovoltaics

Despite the fact that perovskite solar cells (PSCs) have made rapid progress as a promising photovoltaic technology, defect management at the interface between the electron transport layer (ETL) and perovskite layer remains critical to significantly reduce energy loss of devices. Therefore, developing a robust and effective interlayer is imperative. Herein, 2D Ag doped ZIF-67 (Ag-ZIF) is designed by a solvent modulated strategy based on mixed N, N-dimethylformamide and ethanol, and further applied as an interfacial modifier in PSCs. Since the exposed dimethylimidazole ligands carried by Ag-ZIF and the metal ions, the oxygen vacancies on the SnO2 surface and the uncoordinated Pb2+ and halogen ions at the bottom of the perovskite layer could be passivated effectively. Thus, suppressed non-radiative recombination and accelerated electron transport are achieved. Meanwhile, the robust framework and ultraviolet (UV)-resistant ability of Ag-ZIF could regulate the crystallization of perovskite film and prevent device from UV degradation. Consequently, the efficiency of PSC is remarkably boosted from 18.49% to 21.25% in accompany with enhanced UV and environmental stability.