Figure 7
From: Colloidal lead halide perovskite nanocrystals: synthesis, optical properties and applications
(a) UV-visible absorption (solid lines) and PL spectra (dotted lines) of2D CH3NH3PbI3 NCs consisting of n=1,2 and 3 layers. Reproduced from Hassan et al.86 (b) Bandgap dependence on the number of layers in nanoplatelets of CH3NH3PbX3 (X=I, Br), obtained from theoretical calculations. Reproduced from Saprori et al.87 (c) Structural representation of a monolayer (C4H9NH3)2PbBr4 perovskite. (d) Optical microscopy image of such 2D perovskite platelets grown on substrates. Scale bar: 10 μm. (e) AFM image of single layer perovskite platelets. The inset shows the height profile with the thickness of 1.6 nm. Reproduced from Dou et al.91
