In this paper, three kinds of heterostructure of TiO2/ZnO were fabricated by combining electrochemical, sputtering and/or hydrothermal methods. The crystal structure and morphology of ZnO/TiO2 were studied by the X-ray diffraction method (XRD), scanning electron microscopy method (SEM), atomic force microscopy method (AFM). The photocatalytic performance of the TiO2/ZnO heterostructures was examined by monitoring the degradation of methylene blue (MB) under ultraviolet (UV) or visible light irradiation. The results show that all the TiO2/ZnO heterostructures exhibited the right crystal structure of ZnO and TiO2 phases. All the TiO2/ZnO heterostructures presented superior photocatalytic activities as compared to the TiO2 or ZnO single material. In addition, amongst the three heterostructures, the TiO2-hydrothermal/ZnO rod obtained the highest reaction rate constant (0,065 min-1; 0,056 min-1), followed by TiO2/ZnO rod structure (0,054 min-1; 0,031 min-1), and double-layer TiO2/ZnO (0,05 min-1; 0,021 min-1) under UV light and visible light respectively, primarily due to the effects of enhanced charge separation and generation and the characteristics of the surface area of each heterostructure.
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