▎ 摘　　要

Iron and cobalt materials have attracted enormous interest as low-cost alternatives to noble-metal catalysts able to catalyse oxygen reduction reaction. Here, the effect of the heteropolyacid H(3)PMo(12)o(40) (HPMo) into the structure of new composites formed by Fe, Co and reduced-graphene oxide/chitosan (rGOCS) has been investigated. Chitosan was used as a nitrogen precursor for nanocarbon, while reduced graphene oxide was introduced to tune the electrical conductivity. The physicochemical properties of electrocatalysts were performed "by Raman, XRD, XPS and TEM. Activity toward ORR was carried out in a three electrode electrochemical cell using a rotating disk electrode (RDE). The molybdophosphoric acid incorporation into the structure of Fe/rGOCS composites resulted in an increase of the activity of the oxygen reduction reaction in alkaline medium. Furthermore, the replacement of iron by cobalt yielded in a great improvement of the activity and stability, which may open new avenues for the design of nanomaterials utilizing HPMo/reducedgraphene oxide/chitosan composites. (C) 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.