Cobalt‐Containing Nitrogen‐Doped Carbon Aerogels as Efficient Electrocatalysts for the Oxygen Reduction Reaction

Abstract

Abstract The electrocatalysis of the oxygen reduction reaction (ORR) on cobalt‐containing nitrogen‐doped carbon aerogels (CAs) was studied in alkaline solution. CA‐based catalyst materials with varied compositions were prepared through the sol‐gel polymerisation of organic precursors (resorcinol derivatives and melamine), followed by insertion of Co by using an ion‐exchange process and pyrolysis. The concentrations of the precursors had a large effect on the structure and physicochemical properties of the materials, as characterised by using SEM, XRD, XPS, atomic adsorption spectroscopy, and N 2 ‐adsorption analysis. The electrocatalytic activity of Co‐containing N‐doped CAs for the ORR was higher than that of nitrogen‐free CA, and this activity increased with increasing Co content. The most active catalyst materials supported the four‐electron reduction of O 2 and short‐term stability tests indicated their high durability. Co‐containing N‐doped CAs can be regarded as a promising class of material for the cathode catalysts of alkaline membrane fuel cells.