Help nanorods “stand” on microsubstrate to form hierarchical ZnOnanorod-nanosheet architectures

Abstract

ZnO nanorods were helped to “stand” vertically on microsubstrates by an interesting seed-mediated approach. Taking ZnO nanosheets as the microsubstrates, ZnO nanorods can grow vertically, not lying horizontally, on the facets with the aid of a seed layer precoating to form hierarchical ZnO nanorod-nanosheet architectures. The diameter as well as the length of the standing nanorods can be controlled effectively by adjusting the growth time and ammonia amount in the growth solution. The precoated seed layer has been found to be the key factor in determining the resultant morphology. Room-temperature photoluminescence studies revealed that the near band-edge (NBE) emission intensity of the hierarchical architectures was increased greatly compared with that of bare ZnO nanosheets. These special hierarchical architectures make them appealing for future microdevice applications.