A Platinum-Vanadium Nitride/Porous Graphitic Nanocarbon Composite as an Excellent Catalyst for the Oxygen Reduction Reaction

The oxygen reduction reaction (ORR) is a crucial process not only in fuel cells, but also in metal-air batteries, thus its electrocatalysts have attracted considerable attention. Here, we report the use of a vanadium nitride/porous graphitic nanocarbon (VN/PGNC) composite as an efficient support for a platinum electrocatalyst towards ORR. The VN/PGNC composite was synthesized through a gel-coordination pyrolytic route. The gelatinous precursor formed by the coordination of VO3-, Ni2+, tetraethyl orthosilicate (TEOS), and glucose, followed by a carbonization-nitridation and a subsequent acid-treatment process, led to the formation of the VN/PGNC composite with a large surface area of 879.0m(2)g(-1). The synthetic 10% Pt-VN/PGNC catalyst exhibited excellent ORR performance with more positive onset potential (1.02V), 1.2 times higher mass activity (135.5mAmg(-1)), 0.4 times higher specific activity (4.15mAcm(-2)), and better cyclic stability compared with the commercial 20% Pt/C catalyst. The 10% Pt-VN/PGNC catalyst mainly exhibits a four-electron pathway. The excellent performance of 10% Pt-VN/PGNC catalyst is attributed to the porous structure of the support, which facilitates strong synergistic effects between the Pt and VN nanoparticles. The present work provides a cost-effective route for the synthesis of the efficient ORR catalyst, which could promote the development of fuel cells.