Affiliation: | a Department of Chemical Engineering and Technology, Chemical Reaction Engineering, KTH-Royal Institute of Technology, S-100 44, Stockholm, Sweden b Laboratory of Materials Processing and Powder Metallurgy, Helsinki University of Technology, P.O. Box 6200, FIN-02015, Hut, Finland |
Abstract: | Raney nickel and its alloys with the transition metals were prepared and investigated as gas diffusion electrodes for the hydrogen oxidation reaction (HOR) in 6 M KOH and at 60 °C. The spongy Raney nickel prepared by a mixture of Ni and Al with a weight ratio of 1:1 was compared for the catalytic activity as hydrogen electrodes with other alloy formations containing 2 wt.% of Cu, Fe, Cr, Ti and La. Depending on the composition of the active layer, the electrocatalytic activity of the Raney nickel was found to decrease in a descending order of the doped metals: Cr>La>Ti>Cu>Fe and with no admixture. The catalytic response of the electrodes, especially for the Cr and Ti-based Raney Ni showed high enrichment and aggregation on the surface and hence affects the activity and stability. Surface area, particle size, average pore diameter, particle morphology and surface elements of the various alloy combinations, have been analyzed and assessed using BET-specific surface areas, SEM and EDXS. |