Iron‐ and Nitrogen‐Doped Graphene‐Based Catalysts for Fuel Cell Applications

Abstract

Abstract A simple synthesis method was used to prepare an active oxygen reduction reaction (ORR) electrocatalyst based on iron and nitrogen co‐doped graphene for polymer electrolyte fuel cell applications. For the synthesis of the ORR catalysts, two different graphene‐based materials, commercially available graphene (Gra) and graphene oxide (GO), were used as the carbon substrates. The half‐cell experiments conducted by using the rotating disc electrode (RDE) method revealed that Fe−N−Gra showed much higher ORR electrocatalytic activity than Fe−N−GO in alkaline medium. This is attributed to the higher surface area, micro‐/mesoporous nature and larger amount of Fe‐N x /amine moieties present in Fe−N−Gra compared to Fe−N−GO, as shown by different physicochemical methods. Almost half of the iron was confirmed to be in highly active Fe‐N x form by 57 Fe Mössbauer spectroscopy. Thus, the Fe−N−Gra as ORR catalyst was further selected to apply this for both proton exchange membrane (PEM) and anion exchange membrane (AEM) fuel cell tests.