Ligand-Tuned Shape Control, Oriented Assembly, and Electrochemical Characterization of Colloidal ZnTe Nanocrystals

A novel ligand tuning strategy for the synthesis and assembly of ZnTe nanocrystals is proposed in this paper: a specific ligand is selected to work with the reaction system to regulate (passivate or activate) the reactivity of zinc precursors, as well as the growth and the assembly of resulting nanocrystals in a coordinate way. By utilization of this strategy, high-quality ZnTe nanodots, branched-nanorods (including nanotetrapods), nanowires and microspheres are obtained. Furthermore, by using ZnTe microspheres as building blocks, ordered two-dimensional (2D) and three-dimensional (3D) arrays and well-defined hollow microspheres are fabricated. The size, morphology, and crystal structure of as-prepared ZnTe nanocrystals are well characterized. The underlying mechanisms for ligand-tuned synthesis and assembly of ZnTe nanocrystals are also intensively discussed. Finally, the shape-dependent optical, structural, and electrochemical properties of those ZnTe nanocrystals are systemically investigated; their band edge positions are studied by cyclic voltammetry.