An efficient Co-WN/CNTs composite catalyst with multiple active sites for oxygen reduction reaction activity

Abstract Cobalt modified tungsten nitride catalyst supported on carbon nanotubes (Co-WN/CNTs) was synthesized through electrospinning and heat treatment, in which WN and Co were uniformly dispersed in N-doped CNTs. The migration of small-sized Co in graphitized carbon results in formation of CNTs when heat-treated. WN, Co element, Co3+, and organic-N constitute multiple active sites of the catalyst, and high graphitized carbon provides strong charge transfer ability and good conductivity for electron. The excellent oxygen reduction activity, efficient four-electron reactions and the stable multiple cycles of Co-WN/CNTs catalyst depend on the multiple active sites and their high dispersion in graphitized carbon.