Effect of morphology of CsPbBr₃ nanocrystals on their optical properties

In this paper, the morphology of CsPbBr₃ nanocrystals (NCs) is controlled by changing the molar ratios of oleylamine (OAm) and propionic acid (PA). The relative ratio plays an important role in the evolution of morphology. The CsPbBr₃ NCs exhibit monoclinic morphology when the molar ratio of OAm/PA is equivalent. When the molar ratio of OAm/PA deviates from 1:1, CsPbBr₃ NCs tend to grow in a sheet shape. The nanosheets with 200∼500 nm and thickness ∼15 nm were synthesized as the molar ratio of OAm/PA (1:4). The PL intensity decreases with the increase of size. The fluorescence lifetime shows a trend of gradual shortening. (paper)