A novel non-precious metal catalyst synthesized via pyrolysis of polyaniline-coated tungsten carbide particles for oxygen reduction reaction

In this paper, a novel non-precious metal catalyst, W-N-C, for oxygen reduction reaction (ORR), has been synthesized via the pyrolysis of polyaniline-coated tungsten carbide particles. The electrocatalytic measurements show that the W-N-C catalyst exhibits a high catalytic activity and long-term stability for ORR in acid media. The ORR onset potential, half-wave potential, and diffusion-limited current density of W-N-C catalyst are measured at 0.82 V. 0.55 V. and 1.54 mA cm(-2), respectively. TEM and XPS measurements indicate that the W-N-C catalyst has nanoshell structure and a high ratio of the graphitic N, which are responsible for high ORR activity and stability. (C) 2012 Elsevier B.V. All rights reserved.