Effect of carbon supports on oxygen reduction reaction of iron/cobalt electrocatalyst

Abstract

Dual metal FeCo has great potential as Pt-free catalyst in various applications, such as cathodic catalyst for fuel cells, in order to reduce the cost significantly and make fuel cell commercialization, viable. In this study, dual metal FeCo catalyst supported on carbon Vulcan XC-72, carbon nanotubes (CNT), and reduced graphene oxide (rGO) were successfully prepared via facile co-precipitation method with varying weight ratios of Fe and Co. The structure of the as-prepared catalysts was characterized by powder X-ray diffraction (XRD), scanning electron micrographs (SEM), and X-ray photoelectron spectroscopy (XPS). The XPS analysis revealed that CoFe2O4 were present on the catalyst particle surface with different Fe to Co ratio. The emergence of the new peak at 530.5 eV is assigned to the deposition of CoFe2O4, which is enabled via Fe-O-Co bonds. The FeCo/rGO catalyst with weight ratio of 2:1 exhibited the optimum performance for oxygen reduction reaction (ORR), with reduction peak of 0.163 mA cm-2 at 0.385 V vs. Ag/AgCl in an acidic media. The experimental result suggested that the dual metal FeCo catalyst display favourable electrocatalytic activity towards ORR and appears to be a promising cathodic electrocatalyst for an acidic fuel cell.