Transition metal-nitrogen co-doped carbide-derived carbon catalysts for oxygen reduction reaction in alkaline direct methanol fuel cell

Abstract

In this work, we demonstrate the electrocatalytic properties of cobalt- and iron-containing nitrogen-doped carbide-derived carbon materials in the oxygen reduction reaction (ORR) and utilise these as cathode catalysts in an alkaline direct methanol fuel cell. The carbide-derived carbon material is produced by chlorination of titanium carbide, which is then pyrolysed in the presence of dicyandiamide and either a cobalt or iron salt. The electrocatalytic activity towards the ORR and stability of the catalyst materials is tested in 0.1M KOH solution employing the rotating disk electrode (RDE) method and compared to a commercial Pt/C catalyst. The elemental composition in the bulk of the materials is studied using energy dispersive X-ray spectroscopy and on the surface by X-ray photoelectron spectroscopy. Scanning electron microscopy is used to investigate the surface morphology of the resulting catalysts. The performance of the catalysts is also compared in alkaline direct methanol fuel cell. The catalysts’ performance is comparable to that of Pt/C in both RDE and fuel cell measurements and rather peculiar morphologies are observed by the growth of carbon nanotubes during pyrolysis. Overall, these novel catalysts show great potential for application in alkaline direct methanol fuel cells.