In-situ reduced petal-like cobalt on Ni foam based cobaltosic oxide as an efficient catalyst for hydrogen peroxide electroreduction

Petal shaped Co/Co3O4 composite electrocatalyst with a special structure used as a cathode for H2O2 electroreduction is obtained by a route of hydrothermal synthesis and in-situ chemical reduction. The phase composition and microstructure of the electrocatalyst are characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Electrochemical performance of H2O2 electroreduction on the Co/Co3O4 petals (Ps) is explored by cyclic voltammetry (CV), chronoamperometry (CA) and electrochemical impedance spectrometry (EIS). The Co/Co3O4 Ps exhibits a higher conductivity than single Co3O4, which leads to a better catalytic activity and stability toward H2O2 electroreduction. In a solution of 3 mol NaOH and 0.5 mol L-1 H2O2, the current density of H2O2 electroreduction on Co/Co3O4 Ps is 440 mA cm(-2) at -0.8 V, higher than that on Co3O4, which make the obtained Co/Co3O4 Ps an excellent alternative catalyst for H2O2 fuel cell. (C) 2017 Elsevier B.V. All rights reserved.