Plasma in liquids induced modification of Cu surfaces

Abstract

Abstract Copper oxide surfaces are commonly used as the catalyst for the CO2 reduction reaction towards hydrocarbons. However, the lifetime of these catalyst surfaces is limited. In this paper, a method of production of copper oxides through in-liquid plasma is explored, which may be a suitable reactivation method in such applications. The influence of the plasma, ignited in distilled water, with copper and its oxides is monitored in − situ using infrared spectroscopy and ex-situ using scanning electron spectroscop and x-ray photoelectron spectroscopy of the samples. It is shown that the interaction of the plasma with the samples causes a reduction of the copper oxide on a fast time scale and an oxidation on a longer time scale. The formation of preferentially oriented copper nanocubes is observed.