CuO Nanowires Can Be Synthesized by Heating Copper Substrates in Air

TLDR

The study presents a vapor‑phase method for synthesizing CuO nanowires on copper substrates such as grids, foils, and wires. CuO nanowires are grown by thermally oxidizing copper substrates in air between 400 and 700 °C, with a proposed growth mechanism involving surface oxidation and crystal twinning. The resulting nanowires have controllable diameters of 30–100 nm, lengths up to 15 μm, and are bicrystalline with a central (111) twin plane.

Abstract

This paper describes a vapor-phase approach to the facial synthesis of cupric oxide (CuO) nanowires supported on the surfaces of various copper substrates that include grids, foils, and wires. A typical procedure simply involved the thermal oxidation of these substrates in air and within the temperature range from 400 to 700 °C. Electron microscopic studies indicated that these nanowires had a controllable diameter in the range of 30−100 nm with lengths of up to 15 μm by varying the temperature and growth time. Electron diffraction and high-resolution TEM studies implied that each CuO nanowire was a bicrystal divided by a (111) twin plane in its middle along the longitudinal axis. A possible mechanism was also proposed to account for the growth of these CuO nanowires.