Preparation of small-sized tungsten carbide nanorods for loading Pt with promoted electrocatalytic activity and stable anti-poisoning performance

Abstract

The Pt-like behavior and synergistic effect of tungsten carbides (WCs) are increased with decreased size and affected by their morphology. However, achieving high specific surface areas of nanostructured WCs with a small size and controlled morphology remains a considerable challenge. In the present studies, WC nanorods with a diameter and length of approximately 50 and 100–300 nm, respectively, were prepared. The morphology of the obtained WO₃·H₂O was controlled by adding citric acid to the reaction solution. The secondary growth of WO₃·H₂O crystals was efficiently restrained because double-walled carbon nanotubes were homogenously dispersed in the solution. When the WO₃·H₂O nanorods were heated in air and carbonized in a nitrogen atmosphere, small-sized WC nanorods with a high specific surface area (32.2 m² g⁻¹) were obtained. Furthermore, the obtained catalysts displayed improved electrocatalytic activity and stable anti-poisoning performance when the WC nanorods were used as a support for loading platinum nanoparticles. All these results indicate the potential application of WC nanorods in electrochemistry and related fields.