Electrocatalytic activity of the nanostructured Au–Co catalyst deposited onto titanium towards borohydride oxidation

• Deposition of Au–Co catalysts on Ti via electroless Co and galvanic displaced Au.
• Characterization of the catalysts obtained by means of FESEM, EDAX, XRD and ICP-OES.
• Enhanced activity of Au(Co)/Ti catalysts towards the oxidation of H2 and BH4−BH4− ions.
• The long-term CVs show deactivation of Au(Co)/Ti catalysts.

The nanostructured gold–cobalt catalysts were deposited onto titanium surface via galvanic displacement technique. The electrocatalytic activity of the as-prepared nanostructured Au(Co)/Ti catalysts was examined in respect to the oxidation of BH4−BH4− ions in alkaline medium by using of the cyclic voltammetry and chrono-techniques. The nanostructured catalysts were prepared via galvanic displacement reactions between hierarchical Co thin films prepared by electroless deposition and a solution of HAuCl4. The surface morphology and composition of the samples were characterized using Field Emission Scanning Electron Microscopy, Energy Dispersive X-ray Spectroscopy and X-ray diffraction. The prepared nanostructured Au(Co)/Ti catalysts exhibit an enhanced electrochemical activity towards the electro-oxidation of H2 generated by catalytic sodium borohydride hydrolysis and oxidation of BH4−BH4− ions.