Sixfold self-assembled hierarchical structures synthesized by direct annealing of Zn microtips

The novel three-dimensional hierarchical structure is composed of single-crystalline Zn microtips with the converted ZnO coating as stem, and ZnO nanowhiskers as branches. The branched ZnO nanowhiskers exhibit preferred growth direction, suggesting that the branched nanostructures might have a preferred orientation, and maintain a well-defined relationship to the Zn stem.