Enhanced electrochemical reduction of hydrogen peroxide by Co3O4 nanowire electrode

Crystalline Co3O4 nanowire arrays with different morphologies grown on Ni foam were investigated by varying the reaction temperature, the concentration of precursors, and reaction time. The Co3O4 nanowires synthesized under typical reaction condition had a diameter range of approximately 500–900 nm with a length of 17 µm. Electrochemical reduction of hydrogen peroxide (H2O2) of the optimized Co3O4 nanowire electrode was studied by cyclic voltammetry. A high current density of 101.8 mA cm−2 was obtained at −0.4 V in a solution of 0.4 M H2O2 and 3.0 M NaOH at room temperature compared to 85.8 mA cm−2 at −0.35 V of the Co3O4 nanoparticle electrode. Results clearly indicated that the Ni foam supported Co3O4 nanowire electrode exhibited superior catalytic activity and mass transport kinetics for H2O2 electrochemical reduction.