Preparation and surface modification of uniform ZnO nanorods via a one-step process

Hydrophobic ZnO uniform nanorods were successfully produced via a one-step process through precipitation transformation reaction in aqueous solution of ZnSO4, Na2CO3 and NaOH with sodium oleate (C17H33COONa) as a modifying agent. Sodium oleate was used to control the size and modify the surface property of the nanorods produced from the precipitation transformation reaction. Measurements of relative contact angle and active ratio indicated that ZnO nanorods were hydrophobic. Scanning electron microscope, X-ray diffraction, XPS analysis, and thermogravimetric analysis were applied. These results suggested that the hydrophobic property was attributed to the presence of a thin layer of zinc oleate, which was bonded onto the surface of ZnO nanorods during the reaction process. The effect of surface modification on morphology, and size of ZnO nanorods and the mechanism of surface modification were preliminary presented. This work provided an approach to control the uniform growth of ZnO nanorods and enhance interfacial compatibility between ZnO powders and organic matrixes by treating the surface with certain capping molecules.