Hydrothermal growth of single crystal ZnO nanorods on surface-modified graphite

ZnO nanostructures were hydrothermally grown at 90°C on bare and surface-modified graphite. Thermodynamically active sites along the grain boundaries on the graphite surface initiated scattered nucleation of ZnO, leading to the formation of a bunched structure. The uniformity of nucleation and the size distribution of nanorods were controlled by modifying the graphite surface with a seed layer. The seed layer was created on the graphite rod by coating it with ethanolic solution of zinc acetate followed by baking at 300°C. The preformed particles on this layer acted as nucleation center for subsequent growth of ZnO nanorods. The resulting ZnO nanorods were vertically well-aligned single crystals, exhibiting strong band edge luminescence.