A facile route to carbide-based electrocatalytic nanocomposites

Abstract

Tungsten carbide nanoparticles with diameters less than 10 nm on graphitic carbon (WC@GC) produced from green foxtail grass under catalysis of iron salts have been successfully synthesized by an efficient method for the first time. The materials were characterized by physical and electrochemical techniques. The results showed that the Pt particles and WC on GC have excellent properties as an electrocatalyst for methanol oxidation. The Pt/WC@GC electrocatalyst is over 5 times higher in peak current density at 0.4 V, and 100 mV more negative in onset potential for methanol oxidation reaction than that on the commercial Pt/C electrocatalyst. Since Pt/WC@GC carries higher catalytic activity compared with Pt/C due to its synergistic effect, less Pt will be required for the same performance and it will in turn reduce the cost of fuel cell electrocatalyst. This work demonstrated that the natural plants could be used to uptake targeting precursors for preparing functional materials. The present method is simple, rapid, and scalable to mass production of the nanomaterials. WC@GC is an applicable support material since the composite carbide and graphite particles are electrically conductive and consist of stable components.