Enhanced electrochemical reduction of hydrogen peroxide by Co3O4 nanowire electrode

Crystalline Co 3 O 4 nanowire arrays with different morphologies grown on Ni foam were investigated by varying the reaction temperature, the concentration of precursors, and reaction time. The Co 3 O 4 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 (H 2 O 2 ) of the optimized Co 3 O 4 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 H 2 O 2 and 3.0 M NaOH at room temperature compared to 85.8 mA cm −2 at −0.35 V of the Co 3 O 4 nanoparticle electrode. Results clearly indicated that the Ni foam supported Co 3 O 4 nanowire electrode exhibited superior catalytic activity and mass transport kinetics for H 2 O 2 electrochemical reduction.