Chloride–bromide co‐engineering enables operationally stable quasi‐2D tin perovskite solar cells under ambient conditions
Quasi‐two‐dimensional (q‐2D) tin perovskites (TPs) are a promising solution to the inherent instability of TP solar cells (TPSCs). However, studies on their operational stability in uncontrolled ambient conditions are limited due to instabilities arising from mixed lower dimensional phases and the intrinsic rapid o...