Photo Stabilization of p‐i‐n Perovskite Solar Cells with Bathocuproine: MXene

Abstract Interface engineering is one of the promising strategies for the long‐term stabilization of perovskite solar cells (PSCs), preventing chemical decomposition induced by external agents and promoting fast charge transfer. Recently, MXenes–2D structured transition metal carbides and nitrides with various functionalization (O, ‐F, ‐OH) have demonstrated high potential for mastering the work function in halide perovskite absorbers and have significantly improved the n‐type charge collection in solar cells. This work demonstrates that MXenes allow for efficient stabilization of PSCs besides improving their performances. A mixed composite bathocuproine:MXene, that is, (BCP:MXene) interlayer, is introduced at the interface between an electron‐transport layer (ETL) and a metal cathode in the p‐i‐n device structure. The investigation demonstrates that the use of BCP:MXene interlayer slightly increases the power conversation efficiency (PCE) for PSCs (from 16.5 for reference to 17.5%) but dramatically improves the out of Glove‐Box stability. Under ISOS‐L‐2 light soaking stress at 63 ± 1.5 °C, the T80 (time needed to reduce efficiency down to 80% of the initial one) period increases from 460 to > 2300 hours (h).