A seed-mediated growth method for vertical array of single-crystalline CuO nanowires on surfaces

The preparation and characterization of a large-scale vertical array of single-crystalline CuO nanowires on different material surfaces is demonstrated for the first time. The procedure simply involved a room-temperatures liquid-solid growth process of attached CuO nanoseeds on ITO surface in the mixed aqueous solution of Cu(CH3COO)(2) and NH3. By controlling the concentration of the chemical precursors in the growth solution, we can fabricate variable-shape ID structures of CuO, such as nanowires and nanobelts. The FESEM image analysis indicated that these nanowires feature uniform size with tiny structures that have diameters and lengths in the range of 10 and 100 urn, respectively, and tend to form a bundlelike structure at the top end of the wires. The high-resolution transmission electron microscopy (HRTEM) study on individual CuO NWs reveals that the NWs are single-crystalline with growth orientation is [110]. The XRD analysis of the samples revealed that the nanostructures were a high-crystalline CuO without the presence of other phases of the Cu complexes. A possible mechanism that accounts for the growth of these nanostructures using the present techniques was described.