Structure and optical properties of individual hierarchical ZnS nanobelt/ZnO nanorod heterostructures

Here, we report the synthesis and characterization of high-quality hierarchical ZnS nanobelt/ZnO nanorod heterostructures by a simple two-step vapor-phase transport method. On the basis of TEM results, ZnO nanorods epitaxially grew on the side surfaces of ZnS nanobelt along ±[001] directions, resulting in the hierarchical ZnS/ZnO nano-heterostructures having an important feature of single crystallinity. Cathodoluminescence(CL) studies of single ZnS nanobelt and ZnS/ZnO nano-heterostructures reveal that the bandgap emission of the ZnS component was almost totally quenched after the growth of ZnO nanorods on ZnS nanobelt. In addition, high-spatial resolution CL results indicate that the ZnS component contributes more to the green emission of ZnS/ZnO nano-heterostructures than the ZnO component.