Electrocatalysis of hydrogen evolution reaction on tri-metallic Rh@Pd/Pt(poly) electrode

Hydrogen evolution reaction (HER) was investigated in alkaline solution on tri-metallic Rh@Pd/Pt(poly) electrode, prepared by spontaneous deposition of Rh on top of Pd/Pt(poly) electrode with intermediate Pd coverage of 35%. Characterization of tri-metallic catalyst was performed by electrochemical methods of cyclic voltammetry and CO stripping voltammetry, while its activity for HER was tested by linear sweep voltammetry in 0.1 M NaOH. Rh@Pd/Pt(poly) catalyst has shown superior catalytic activity for HER with respect to initial Pt(poly) and both corresponding bimetallic Pd/Pt(poly) and Rh/Pt(poly) electrodes. This was explained by a strong synergistic electronic interaction between three metals in close contact induced at a number of different active sites across the surface of tri-metallic catalyst, which results with lowering of the binding energy for the adsorption of H intermediate species.