Functional CuO nanowire bundle growth on ITO from a novel spin coatable seed layer and electrochemical route

We present a straightforward, fast, and inexpensive electrochemical method to grow functional CuO nanowire bundles on indium-tin-oxide (ITO) glass substrates from a spin-coatable organocopper precursor. We show the critical effect the preheating conditions have on the morphology, the phase, and the functional nature of the resulting nanostructures, finding that simple hot-plate preheating is optimal over furnace heating in terms of lower overpotential and higher current density output in glucose oxidation. The electrocatalytic activity of the modified ITO electrode for glucose oxidation is presented, and the Tafel slope is calculated to understand the kinetics of glucose oxidation on this electrode. The morphology and the phase are studied by using scanning electron microscopy, transmission electron microscopy, selected area electron diffraction, and Raman spectroscopy and confirm the monoclinic single-phase CuO of the nanowire bundles. This commercially available organocopper precursor enables growth of functional CuO nanowire bundles without the need for vacuum deposition or high- temperature treatment. Moreover, the spin-coatable nature of this precursor facilitates functional and crystalline CuO nanostructure growth on a variety of substrates at room temperature.