Hydrothermal Preparation and Photoluminescence Property of Co-Doped ZnO Nanorods

Pure and Co-doped ZnO nanorods were synthesized by hydrothermal method at low temperature using Zn(NO3)2·6H2O and Co(NO3)2·6H2O as raw materials. The as-prepared samples were studied by XRD, EDS, TEM, and HRTEM, the photoluminescence (PL) property of the samples was principally investigated by PL spectroscopy. The results showed that the crystallinities of pure and ZnO:Co nanorods were rather well. Co atoms substituted Zn atoms positions to incorporate into nanocrystal, the dopant content was about 2%(atomic fraction). The average diameter and length of pure ZnO nanorods were about 20 and 180 nm, whereas the corresponding parameters of doped nanorods were respectively about 15 and 200 nm. This indicated that Co doping could influence the growth of ZnO nanorods. In addition, the Co doping could tune the energy level structure and enrich the surface states of ZnO nanorods, which led to emission peak redshift in UV region and luminescence enhancement in visible light region.