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

Abstract Petal shaped Co/Co 3 O 4 composite electrocatalyst with a special structure used as a cathode for H 2 O 2 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 H 2 O 2 electroreduction on the Co/Co 3 O 4 petals (Ps) is explored by cyclic voltammetry (CV), chronoamperometry (CA) and electrochemical impedance spectrometry (EIS). The Co/Co 3 O 4 Ps exhibits a higher conductivity than single Co 3 O 4 , which leads to a better catalytic activity and stability toward H 2 O 2 electroreduction. In a solution of 3 mol L − 1 NaOH and 0.5 mol L − 1 H 2 O 2 , the current density of H 2 O 2 electroreduction on Co/Co 3 O 4 Ps is 440 mA cm − 2 at − 0.8 V, higher than that on Co 3 O 4 , which make the obtained Co/Co 3 O 4 Ps an excellent alternative catalyst for H 2 O 2 fuel cell.