Synthesis and characterization of Iron and Nitrogen functionalised graphene catalysts for oxygen reduction reaction

ArticleinApplied Organometallic Chemistry 31(10) · December 2016with 116 Reads
DOI: 10.1002/aoc.3738
Abstract
In the present study, iron and nitrogen functionalised graphene (Fe-N-G), as well as iron and nitrogen functionalized oxidized graphene (Fe-N-oxG) catalysts were synthesized as non-noble metal electrocatalysts for oxygen reduction reaction (ORR). The physical properties of the resultant catalysts were characterised by N2 adsorption, X-ray diffraction (XRD), Raman spectra and X-ray photoelectron spectroscopy (XPS) and Transition electron microscopy (TEM) image analyses. Subsequently, ORR activities of the catalysts were determined electrochemically using a conventional three-electrode cell via a cyclic voltammetry using a rotating disk electrode (RDE). The RDE results indicated that the synthesized iron and nitrogen functionalised graphene catalysts have the remarkable electrocatalytic activity towards the ORR in acid media. Among the synthesized catalysts in present study, iron and nitrogen functionalised graphene using 2,4,6-Tris (2-pyridyl)-1,3,5-triazine (TPTZ) for nitrogen source [Fe-N(TPNZ)-G] had highest electrocatalytic activity with the highest onset potential (0.98 V/SHE) and limiting current densities (5.12 mA/cm2). The findings of the present study are particularly important to determine a non-precious metal catalyst for ORR activity in fuel cells.

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