Antimony trifluoride-incorporated SnO2 for high-efficiency planar perovskite solar cells

The low-cost material antimony trifluoride (SbF3) was doped into commonly used tin dioxide (SnO2) for the first time, and the SbF3-doped SnO2 as an electron-transport layer (ETL) was successfully applied in perovskite solar cells (PSCs). After the SbF3 doping, the optimized photovoltaic power conversion efficiency (PCE) was significantly enhanced from 19.89% to 21.42%. The effects of SbF3 on the device performance were then systematically investigated. The results show that the electron mobility of the ETL is markedly increased and the quality of the ETL/perovskite interface is effectively improved, which is helpful to promote the electron-transport efficiency in the ETL as well as the electron-extraction ability from the perovskite to the ETL. Besides, the perovskite grain size is clearly increased and the trap state density in the bulk perovskite is significantly decreased, both of which can greatly suppress charge-carrier recombination in the perovskite film. Moreover, the device based on the SbF3-doped SnO2 ETL displays negligible hysteresis and excellent stability.