In situ formation of inorganic healing overlayer for interface-stabilized all-inorganic CsPbIBr 2 perovskite solar cells

layer to solidify the soft perovskite lattice. As a result of defect passivation and self-encapsulation, the best device achieved an enhanced efficiency of up to 10.12%, which was much higher than the 7.47% efficiency for the reference device tested, with prolonged stability under conditions of persistent light irradiation and exposure to air.