Carbon-Doped Copper (hydro)Oxides on Copper Wires as Self-supported Bifunctional Catalytic Electrode for Full Water Splitting

A doped carbon-copper (hydro)oxides self-supported catalytic electrode, CW@C/CuO/Cu 2 O/Cu(OH) 2 NPs, has been built by hydrothermal synthesis in this work. In an alkaline solution for full water splitting, the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER) catalyzed by the novel electrode occurs at the range of − 0.1 V ~ + 0.2 V and + 0.5 V ~ + 1.0 V, respectively. The current densities of the both processes reached 226 mA cm −2 . The activity of the electrode can be restored by the conversion between Cu (II) and Cu (I). The high electronic conductivity and activity might be caused by villous and porous structures and the fabricated craft of material directly grown on the copper wires (CWs). Graphical Abstract