Co and N co-modified carbon nanotubes as efficient electrocatalyst for oxygen reduction reaction

It is a big challenge to prepare non-rare metal and high-activity electrocatalysts for oxygen reduction reaction (ORR). In this paper, a cobalt/carbon nanotubes/chitosan composite gel was synthesized and then annealed under nitrogen atmosphere to yield the cobalt and nitrogen co-modified carbon nanotubes (Co–N-CNTs) nanocomposite electrocatalysts. In this strategy, the cobalt component considerably enhanced the ORR activity and improved the degree of graphitic structure to increase the electronic conductivity. The chitosan served as sustainable source for nitrogen doping. The Co–N-CNTs exhibit excellent oxygen reduction reaction (ORR) electrocatalytic activity due to the synergetic effect of Co species and N-doping. The Co–N-CNTs also deliver excellent methanol tolerance and superior long-term durability to that of commercial Pt/C, making it a promising ORR electrocatalyst.