Angstrom-sized tungsten carbide promoted platinum electrocatalyst for effective oxygen reduction reaction and resource saving

Abstract

Angstrom-sized tungsten carbide dots (WC^dot), WC rods (WC^rod) and 10 nm-sized WC particles (WC^nano) are synthesized and used as platinum (Pt) electrocatalyst supports for efficient oxygen reduction reaction (ORR). The concentration of the tungsten source and formula structure of the carbon source (ion-exchange resin) control the size and shape of the WC materials. The angstrom-sized WC^rod promoted Pt electrocatalyst (Pt/WC^rod) shows slightly higher activity than the 10 nm-sized WC^nano promoted electrocatalyst (Pt/WC^nano), although the WC^rod costs only one tenth the W amount of the WC^nano, indicating resource saving. In addition, the Pt/WC^rod shows higher ORR efficiency and stabilization than the commercial Pt/C. The electron transfer from WC to Pt is believed to account for the excellent performances of the Pt/WC. The significance of the work is that less WC and less Pt can be used to achieve the same or higher ORR performances, and the synthesis method can also be used to synthesize other angstrom-sized materials.