Simple hydrothermal synthesis of mesoporous spinel NiCo2O4 nanoparticles and their catalytic behavior in CH3OH electro-oxidation and H2O2 electro-reduction

Mesoporous spinel NiCo2O4 nanoparticles were synthesized via a simple hydrothermal strategy. Their physicochemical properties were characterized by X-ray diffraction (XRD), scanning electron microscopy-energy dispersive X-ray spectra (SEM-EDS), X-ray photoelectron spectra (XPS) and nitrogen sorption measurements. Their electrocatalytic performances were investigated by cyclic voltammetry (CV), chronoamperomerty (CA) and electrochemical impedance spectroscopy (EIS) tests. The obtained NiCo2O4 materials exhibit a particle size of about 200 nm, a specific surface area (SSA) of 88.94 m(2) g(-1) and a mesopore volume of 0.195 cm(3) g(-1). The binary electroactive sites of Co and Ni species, high electron conductivity and intriguing mesoporous structures of the NiCo2O4 electrode favor its desirable electro-catalytic activity. A current density of 93 mA cm(-2) at 0.6 V in 1 M KOH and 0.5 M CH3OH electrolytes was obtained for CH3OH electro-oxidation, and a current density of 130 mA cm(-2) at -0.3 V in 3 M NaOH and 0.5 M H2O2 electrolytes was achieved for H2O2 electro-reduction. Moreover, the NiCo2O4 electrode exhibits a high stability for both catalytic reactions, showing the potential for further development of high performance non-Pt catalysts based alkaline fuel cells (AFCs).