Effect of UV irradiation on the properties of ZnO nanorod arrays prepared by hydrothermal method

This paper reports a novel phenomenon that the ZnO nanorod arrays hydrothermally grown on the UV-treated area of the ZnO seeding layer exhibit different surface morphology and photoluminescence characteristics compared with those grown on the non-UV-treated area. The diameter distribution of the nanorods on the different areas is different too. The UV treatment makes the ZnO seeding layer hydrophilic, which is the exhibition of the change of the surface energy status. This change will affect the growth behavior of the ZnO nanorod arrays. Patterned ZnO nanorod arrays with different structures on the same substrate can be realized by hydrothermal method employing UV treatment of the ZnO seeding layer. This kind of UV treatment can find other applications in other preparation methods for 1D nanostructures of ZnO and other kinds of materials, and for the research of the hydrothermal growth mechanism of these nanostructures.