Synthesis of long ZnO/ZnS core–shell nanowires and their optical properties

Aligned zinc oxide/zinc sulfide core–shell nanowire arrays are synthesized on transparent conductive oxide (TCO) glass substrate by sulfurizing ZnO nanowires using a vapor phase method. The length of these nanowires is about 7.3   μm with diameter of ~100   nm. The thickness of the ZnS shell can be controlled by adjusting the reaction time. It is found that the shell layer is well crystallized with preferring growth direction of ZnS [002]. The result indicates that when used to decompose methyl orange (MO), the core–shell nanowire arrays have superior photocatalytic performance under UV-light irradiation, which shows considerable potential applications of this nanocomposite in water purification.