Porous VO x N y nanoribbons supported on CNTs as efficient and stable non-noble electrocatalysts for the oxygen reduction reaction

Abstract

Novel nanocomposites of carbon nanotubes supported porous VO x N y nonoribbons (VO x N y -CNTs) have been synthesized by the annealing of the sol-gel mixture of CNTs and V 2 O 5 under NH 3 atmosphere as well as the ageing process in air. Besides the morphological and structural characterizations revealed by TEM, SEAD, EDS, XRD and XPS measurements, typical electrochemical tests including cyclic voltammetry (CV), rotating disk electrode (RDE) and chronoamperometry have been employed to determine the oxygen reduction reaction (ORR) performance of VO x N y -CNTs. Inspiringly, the results indicate that VO x N y -CNTs catalyst exhibits a 0.4 mA/cm 2 larger diffusion-limited current density, a 0.10V smaller onset potential value, a 10.73% less of ORR current decay and an excellent methanol-tolerance compared with commercial Pt/C catalyst. Therefore, we have reasonable grounds to believe that this new VO x N y -CNTs nanocomposites can be regarded as a promising non-precious methanol-tolerant ORR catalyst candidate for alkaline fuel cells.