Formation of niobium oxide nanowires by thermal oxidation

In this report, we describe simple thermal oxidation of niobium for the fabrication of niobium oxides, emphasizing that niobium oxide nanowires can be prepared upon the concentration of oxygen in the environment. For example, dense Nb2O5 nanowires on thin oxide film are produced if the annealing is performed in a restricted concentration of oxygen (herein, 3 Torr vacuum). If most of the oxygen is removed in the environment, the nanowires are sparely formed. The nanowires consist of a superlattice monoclinic Nb2O5 with a growth direction of [0 0 1].