Metal-ZnO heterostructure nanorods with an abrupt interface

We report on metal-semiconductor heterostructure nanorods with an abrupt interface. The metal-semiconductor nanorods were fabricated simply by evaporating metal on vertically aligned ZnO nanorods. Before the fabrication of heterostructure nanorods, the ZnO nanorods were prepared by metalorganic vapor phase epitaxy. Since no metal catalyst is employed during the nanorod growth, the nanorods do not exhibit any metal clusters on their tips. When metal is evaporated on the vertically aligned nanorods, metal is deposited mainly on the tips of the nanorods. Transmission electron microscopy revealed that the Au-coated ZnO heterostructure nanorods exhibit an atomically sharp interface between ZnO and Au.