Fig. 1From: Phase Engineering for Highly Efficient Quasi-Two-Dimensional All-Inorganic Perovskite Light-Emitting Diodes via Adjusting the Ratio of Cs CationAbsorption spectra in thin films of a the 3D CsPbBr3 and 2D PPA2PbBr4 perovskite, and b quasi-2D compounds with different molar ratios of PPA:Cs cations of 2:2, 2:3, 2:3.5, and 2:4. c XRD patterns of quasi-2D perovskite films with molar ratio of PPA:Cs cations of 2:2, 2:3, 2:3.5, and 2:4Back to article page