title: Co-Doping of Activated Graphene for Synergistically Enhanced Electrocatalytic Oxygen Reduction Reaction.
abstract: Doping of graphene has emerged as a key strategy to improve the electrocatalytic performance of the oxygen reduction reaction (ORR). Activated graphene co-doped with iodine and nitrogen atoms (NIG) was developed in this work using a facile scalable approach. The onset potential, current density, and four-electron reduction pathway of the newly developed catalyst were significantly improved. The charge-transfer resistance of co-doped NIG was found to be much lower than nitrogen-doped graphene (NG); furthermore, the stability of NIG and its resistance to methanol crossover were also improved. The synergistically enhanced ORR performance of NIG was found to be a result of a high strain and size advantage of the larger iodine atom clusters (compared to nitrogen), which facilitate the simultaneous enrichment of anode electrons and O2 and H2 O molecule transport at catalytic sites, inducing four-electron transfer in a single step. These results are promising for application in alkaline fuel cells.
authors.affiliation: Integrated Polymer and Systems Engineering Group, School of Chemical and Biomolecular Engineering, The University of Sydney, NSW, 2006, Australia), Fax: (+61) 293512854.
authors.forename: Mahbub
authors.initials: M
authors.lastname: Hassan
authors.affiliation: Integrated Polymer and Systems Engineering Group, School of Chemical and Biomolecular Engineering, The University of Sydney, NSW, 2006, Australia), Fax: (+61) 293512854.
authors.forename: Enamul
authors.initials: E
authors.lastname: Haque
authors.affiliation: Laboratory for Sustainable Technology, School of Chemical and Biomolecular Engineering, The University of Sydney, NSW, 2006, Australia.
authors.forename: Andrew I
authors.initials: AI
authors.lastname: Minett
authors.affiliation: Integrated Polymer and Systems Engineering Group, School of Chemical and Biomolecular Engineering, The University of Sydney, NSW, 2006, Australia), Fax: (+61) 293512854. vincent.gomes@sydney.edu.au.
authors.forename: Vincent G
authors.initials: VG
authors.lastname: Gomes
mesh_terms: D000814:Aniline Compounds / Q000737:chemistry; D002384:Catalysis; D011211:Electric Power Supplies; D004563:Electrochemistry; D006108:Graphite / Q000737:chemistry*; D007455:Iodine / Q000737:chemistry; D008958:Models, Molecular; D008968:Molecular Conformation; D053758:Nanoparticles / Q000737:chemistry; D009584:Nitrogen / Q000737:chemistry; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry*; D013696:Temperature
chemical_list: D000814:Aniline Compounds; C416807:polyaniline; D006108:Graphite; D007455:Iodine; D009584:Nitrogen; D010100:Oxygen
keywords: doping; electrocatalysis; fuel cells; graphene; oxygen reduction reaction