title: Transition metal-depleted graphenes for electrochemical applications via reduction of CO₂ by lithium.
abstract: Graphene has immense potential for future applications in the electrochemical field, such as in supercapacitors, fuel cells, batteries, or sensors. Graphene materials for such applications are typically fabricated through a top-down approach towards oxidation of graphite to graphite oxide, with consequent exfoliation/reduction to yield reduced graphenes. Such a method allows the manufacture of graphenes in gram/kilogram quantities. However, graphenes prepared by this method can contain residual metallic impurities from graphite which dominate the electrochemical properties of the graphene formed. This dominance hampers their electrochemical application. The fabrication of transition metal-depleted graphene is described, using ultrapure CO₂ (with benefits of low cost and easy availability) and elemental lithium by means of reduction of CO₂ to graphene. This preparation method produces graphene of high purity with electrochemical behavior that is not dominated by any residual transition metal impurities which would dramatically alter its electrochemical properties. Wide application of such methodology in industry and research laboratories is foreseen, especially where graphene is used for electrochemical devices.
authors.affiliation: Division of Chemistry & Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, 637371, Singapore.
authors.forename: Hwee Ling
authors.initials: HL
authors.lastname: Poh
authors.forename: Zdenek
authors.initials: Z
authors.lastname: Sofer
authors.forename: Jan
authors.initials: J
authors.lastname: Luxa
authors.forename: Martin
authors.initials: M
authors.lastname: Pumera
mesh_terms: D002245:Carbon Dioxide / Q000737:chemistry; D055664:Electrochemical Techniques; D006108:Graphite / Q000737:chemistry*; D008094:Lithium / Q000737:chemistry; D018625:Microscopy, Atomic Force; D008855:Microscopy, Electron, Scanning; D010084:Oxidation-Reduction; D056951:Photoelectron Spectroscopy; D013059:Spectrum Analysis, Raman; D028561:Transition Elements / Q000737:chemistry
chemical_list: D028561:Transition Elements; D002245:Carbon Dioxide; D006108:Graphite; D008094:Lithium
keywords: carbon dioxide; electrochemistry; graphene; metallic impurities