Selective grain boundary passivation by ammonium nitrate for enhanced performance and stability of FA-Cs based perovskite solar cells.

Grain boundaries of metal halide perovskites contain massive defects that are detrimental to photovoltaics applications. This work demonstrates that inorganic NH 4 NO 3 can selectively passivate the grain boundaries of perovskite films and improve their moisture resistance simultaneously, resulting in enhanced performance and stability of the methylammonium-free perovskite solar cells.