High-density growth of copper oxide nanowires in an oxidative carbon-rich environment

Abstract

Cupric oxide (CuO) nanowires are grown by thermal oxidation of copper (Cu) films in a carbon-rich, ambient-pressure environment. Cu strips are used as metal sources. CuO oxide nanowires grow on oxidized Cu substrate. Nanowires grow persistently with the use of 0.5g and 1.0g activated carbon while micron-sized crystals grow with 3.0g and 5.0g of activated carbon. Optimization of growth time and temperature gives a high yield of vertically aligned nanowires that extend up to 45 μm. There is an observed existence of both Cu2O and CuO phase on oxidized Cu substrate. EDX and FTIR characterization show that the nanowires grown on Cu substrate are made of CuO. Photoluminescence of CuO nanowires shows an energy band gap of 1.43 eV.