Ruthenium-doped 3D Cu2O nanochains as efficient electrocatalyst towards hydrogen evolution and hydrazine oxidation

The sluggish kinetics of oxygen evolution reaction (OER) hampers the conversion of renewable energies into hydrogen through an electrocatalytic process. Then, the hydrazine oxidation reaction (HzOR) is a promising anodic reaction to substitute OER, which can decrease the water-splitting voltage. Herein, self-supported ruthenium-doped cuprous oxide nanochains were synthesized on commercial copper foam (Ru-Cu2O/CF). The Ru-Cu2O/CF provides superior hydrogen evolution reaction (HER) and HzOR performances owing to its specific morphology, superhydrophilic surface, porous support and Ru doping. When used in alkaline or neutral electrolytes, the Ru-Cu2O/CF is capable of driving 10 mA cm−2 only at 31 and 51 mV, respectively. In HzOR, it is possible to achieve a superlow potential of − 41 mV at 10 mA cm−2. In an electrolytic cell with a Ru-Cu2O/CF both as cathode and anode, a voltage of 17.4 mV is needed to reach 10 mA cm−2, which is powered by renewable energies.