Electrooxidation of hydrogen peroxide and sodium borohydride on Ni deposited carbon fiber electrode for alkaline fuel cells

In this study, Ni deposited carbon fiber electrode (Ni/CF) prepared by electroless deposition method was examined for their redox process and electrocatalytic activities during the oxidation of hydrogen peroxide and sodium borohydride in alkaline solutions. The Ni/CF catalyst was characterized by X-ray diffraction (XRD), energy dispersive X-ray analysis (EDAX), scanning electron microscopy (SEM) and electrochemical voltammetry analysis. The electrocatalytic activity of the Ni/CF for oxidation of hydrogen peroxide and sodium borohydride in alkaline solutions was investigated by cyclic voltammetry. The anodic peak current density is found to be three times higher on Ni/CF catalyst for sodium borohydride compared to that for hydrogen peroxide. Preliminary tests on a single cell of a direct borohydride/peroxide fuel cell (DBPFC) and direct peroxide/peroxide fuel cell (DPPFC) indicate that DBPFC with the power density of 5.9 mW cm−2 provides higher performance than DPPFC (3.8 mWcm−2).