Symmetric growth of ZnO nanorod arrays on both the top and bottom polar surfaces of ZnO nanobelts by chemical bath deposition

Brush-like and bridge-like hierarchical ZnO nanostructures were selectively grown on polar surfaces of ZnO nanobelts by chemical bath deposition (CBD). Symmetric growth of ZnO nanorod arrays on both the top and bottom polar surfaces of ZnO nanobelts suggests that the two polar planes have high surface energy and are metastable, which can promote preferred orientation growth along ± [0001] directions. Hierarchical ZnO nanostructures will be served as interconnects and functional components in the “bottom up” design to build up functional devices.