Electrocatalysis by nanocrystalline tungsten carbides and the effects of codeposited silver

The electrocatalytic activity of two nanocrystalline tungsten carbides, WC and W2C, towards the anodic oxidation of hydrogen in 1.5 M H2SO4 at 65 °C is presented. The carbides, which were synthesised by solid-state reduction of W(VI) using carbon, are both electrocatalytic. The WC phase shows greater electrocatalysis than the W2C phase, and also shows a greater degree of passivity against corrosion in the hot sulphuric acid electrolytes. The effect of codeposited silver is to enhance the electrocatalytic activity of the WC phase, whilst not in itself showing any electrocatalysis.