Active copper(Ⅱ) and copper(Ⅰ) reviving repeatedly in situ on copper wire electrode for full water splitting at ultra-low potential

摘要

Searching for inexpensive electrocatalysts for hydrogen and oxygen evolution reaction (HER, OER) with high activity has attracted considerable research interests in the past years. Herein, we report a self-supported electrode of the monolithic copper oxides directly on Cu wires [CW@Cu(I/II)NPs, as a working electrode] for full splitting water. In alkaline solution, with the electrode, OER occurs at the potential scope of 0.00 similar to +0.21 V and HER happens at the range of + 0.85 similar to +1.25 V with rough gas releasing. The activity of the electrode can be retrieved during the interactive electrochemical processes of OER and HER, which process shows decent stability. It is possible to save energy in industrial electrolysis water with the proposed electrode. The phenomena remind us of reassessing electrocatalytic ability of copper oxides or other metal oxides and provide a new design idea for metal wire-based electrodes for water splitting with low energy consumption.