A versatile approach to synthesise optically active hierarchical ZnS/ZnO heterostructures

One-dimensional hierarchical ZnS/ZnO heterostructures have been successfully fabricated by combining thermal evaporation method and in-situ/post oxidation process. Various morphologies of the secondary ZnO nanostructures such as nanosheets, nanoparticles, and nanoteeths were found to form on the ZnS nanowire backbone. The optical properties of the heterostructures were investigated by high-spatial resolution cathodoluminescence spectroscopy. It was demonstrated that optically active hierarchical ZnS/ZnO heterostructures, which strongly emit UV light with two emission bands at around 335 nm and 380 nm characterising both the ZnS and the ZnO phases, can be realised by controlling the oxidation temperature and duration. This research introduces a simple route to synthesise optically active ZnS/ZnO heterostructures.