Fig. 2From: Phase Engineering for Highly Efficient Quasi-Two-Dimensional All-Inorganic Perovskite Light-Emitting Diodes via Adjusting the Ratio of Cs CationSEM images of perovskite films with a 3D perovskite and quasi-2D perovskite based on PPA:Cs cations of b 2:2, c 2:3, d 2:3.5, and e 2:4; the insets show the magnified picture of corresponding SEM. b AFM topographies of corresponding perovskite filmsBack to article page