Blue-emitting and self-assembled thinner perovskite CsPbBr(3)nanoplates: synthesis and formation mechanism

摘要

Low dimensional semiconductor nanomaterials show great promise for a variety of applications due to their size-dependent and excellent optoelectronic properties. In this work, we developed a strategy to synthesize uniform and very thin CsPbBr(3)perovskite nanoplates (NPls) by introducing additional metal bromides. The CsPbBr(3)NPls, self-assembled into a face-to-face stacked state, had a thickness of 4.4 nm (equal to only 2 monolayers, 2 MLs) and showed a maximum emission at 437 nm and a narrow FWHM of 14 nm. The formation mechanism of the CsPbBr(3)NPls by adding FeBr(3)was ascribed to the constrained growth of CsPbBr(3)nanocubes when the surface Cs(+)ions were substituted by the protonated oleylammonium from the byproduct OLA-HBr.