Enhanced activity of molybdovanadophosphoric acid modified Pt electrode for the electrooxidation of methanol

The Keggin-structure molybdovanadophosphoric acid (H3+xPMo12−xVxO40, x = 1, 2, 3, denoted as PMV) modified Pt electrode was studied by electrochemical measurements for methanol oxidation. It was discovered that both the catalytic activity and stability of the PMV modified Pt electrode were significantly enhanced. With the increase of the vanadium content in PMV, the catalytic activity and stability for methanol electrooxidation were also increased. The enhancements were attributed to the special properties of PMV, which increased the electron transfer coefficient of the rate-determining step. Therefore, the PMV has potential application as promoter for methanol electrooxidation in direct methanol fuel cell.

► The PMV modified Pt electrode enhanced the performances for methanol oxidation.
► The Pt–V3 electrode has the best catalytic activity.
► The electron transfer coefficient was increased on the PMV modified Pt electrode.
► The enhancements were attributed to the special properties of PMV.