Sno2/Basno3 Electron Transport Materials for Stable and Efficient Perovskite Solar Cells

TiO2 is one of the most widely used electron transport layer (ETL) materials for the fabrication of perovskite solar cells (PSCs). However, TiO2 has limitations of low electron mobility and poor photo-stability under UV exposure. To solve this issue, we explored SnO2/BaSnO3 (BSO) ETL for a stable and efficient n-i-p PSC with FTO/c-SnO2/ mp-BSO/CH3NH3I/Spiro-OMeTAD/Au configuration. It was found that the compact layer plays an important role in electron transport in ETL, leading to better device performance overall. Compared to the TiO2 based ETL devices, the champion devices with c-SnO2/mp-BSO ETL showed a power conversion efficiency over 15.54%, which is comparable or even better than the previously reported. More importantly, the champion device showed remarkable enhancement of thermal-and photo-stability and long-term air stability.