Nickel-rare earth electrodes for sodium borohydride electrooxidation

Binary alloys of nickel (Ni) and dysprosium (Dy) or samarium (Sm) of different composition were prepared. Their electrocatalytic activity in respect to borohydride oxidation in alkaline medium was investigated by cyclic voltammetry, chronoamperometry and chronopotentiometry. It was correlated to their morphological and structural properties examined by SEM/EDXS and XRPD. Ni0.95Dy0.05 alloy electrode showed the highest electrocatalytic activity for BOR, and Ni0.90Sm0.10 showed the lowest. The activity of the rare earth alloys was compared to other Ni- and Pt-based materials, with promising results being reported, which envisage application of these materials as electrodes in direct borohydride fuel cells. (C) 2015 Elsevier Ltd. All rights reserved.