The effective carbon supported core-shell structure of Ni@Au catalysts for electro-oxidation of borohydride

Carbon-supported Ni-Au nanoparticles with a core-shell structure (Ni@Au/C) are prepared by a combination of reverse microemulsion and two-step reduction. The prepared Ni@Au/C nanoparticles are used as anode electrocatalysts in direct borohydride-hydrogen peroxide fuel cells (DBHFCs). The physical and electrochemical properties of the as-prepared catalysts are investigated using transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), cyclic voltammetry (CV), linear sweep voltammetry (LSV), electrochemical quartz crystal microbalance (EQCM), chronoamperometry (CA), chronopotentiometry (CP) and fuel cell test. The average size of the particles are approximately 10 nm. Among the resultant catalysts obtained in this study, the Ni1@Au1/C catalyst exhibits the highest catalytic activity for the direct electro-oxidation of borohydride. DBHFCs fabricated using Ni1@Au1/C as an anode catalyst and Pt mesh (1 cm × 1 cm) as a cathode electrode achieves a maximum power density of 74 mW cm−2 with a discharge current density of 130 mA cm−2 at 20 °C.