One-pot synthesis of Bi2Se3 nanostructures with rationally tunable morphologies

Abstract

Shape control has proven to be a powerful and versatile means of tailoring the properties of Bi 2 Se 3 nanostructures for a wide variety of applications. Here, three different Bi 2 Se 3 nanostructures, i.e., spiral-type nanoplates, smooth nanoplates, and dendritic nanostructures, were prepared by manipulating the supersaturation level in the synthetic system. This mechanism study indicated that, at low supersaturation, defects in the crystal growth could cause a step edge upon which Bi 2 Se 3 particles were added continuously, leading to the formation of spiral-type nanoplates. At intermediate supersaturation, the aggregation of amorphous Bi 2 Se 3 particles and subsequent recrystallization resulted in the formation of smooth nanoplates. Furthermore, at high supersaturation, polycrystalline Bi 2 Se 3 cores formed initially, on which anisotropic growth of Bi 2 Se 3 occurred. This work not only advances our understanding of the growth mechanism but also offers a new approach to control the morphology of Bi 2 Se 3 nanostructures.