Growth of Cu-Oxide Nanowires on Cu Substrates by Thermal Annealing

Abstract

The CuO/Cu₂O nanowire axial heterostructures were fabricated by a thermal oxidation technique in air. These nanowire structures resulted from CuO nanowire growth followed by Cu₂O formation. These nanowires were divided into two regions. One is the top half part of the nanowire with CuO domains, and the other part is the bottom half of the wires with Cu₂O domains. The structural property of the CuO/Cu₂O nanowire axial heterostructures was clarified in detail. Both the CuO and the Cu₂O have domain boundaries parallel to the growth direction. The specific relationship of the crystalline orientation between the CuO and Cu₂O shows that CuO [110] or [1 10] is nearly parallel to Cu₂O [110] mostly along the growth directions. The growth condition dependence of the morphological structure was also examined. A simple axial nanowire heterostructure fabrication technique using the compositional modification was developed. [DOI: 10.1380/ejssnt.2012.175]