Preparation of Cu2O nanowires by thermal oxidation-plasma reduction method

Abstract

Facial synthesis of cuprous oxide (Cu2O) nanowires by directly heating copper substrates is difficult; however, in this study, it was successfully done by thermal oxidation followed by a plasma reduction process. The preparation of CuO nanowires with an average diameter of 76.2 nm supported on the surface of copper substrate was conducted first in air at 500 °C for 3 hrs, and then the CuO nanowires were reduced into Cu2O in 15 min using either radio frequency (RF) N2 plasma or microwave (MW) N2 plasma. The characteristics of CuO and Cu2O nanowires were analyzed using XRD, FE-SEM, and TEM. The results showed that Cu2O nanowires can be successfully reduced from CuO nanowires by a simple, promising, and fast nitrogen plasma process. Moreover, in RF plasma, narrower and longer Cu2O nanowires can be produced as compared to MW plasma, because energetic N-containing species can reduce the nanowires at a relatively lower temperature.