Controlled synthesis of one-dimensional single-crystal Co3O4 nanowires

Uniform Co3O4 nanowires with diameters of similar to 80 nm and lengths of 10 - 20 mu m have been prepared by a hydrothermal reaction and sequential decomposition of the intermediate product. Transmission electron microscopy characterization and selected-area electron diffraction patterns show that the nanowires elongate along the [ 110] direction. The amount of CO(NH2)(2) employed and the heating rate of calcination have a key effect on the morphology of the product. In addition, analysis of the optical properties indicates a blue shift of the bandgaps and reveals the semiconductive nature of the products.