title: Enhancing the Liquid-Phase Exfoliation of Graphene in Organic Solvents upon Addition of n-Octylbenzene.
abstract: Due to a unique combination of electrical and thermal conductivity, mechanical stiffness, strength and elasticity, graphene became a rising star on the horizon of materials science. This two-dimensional material has found applications in many areas of science ranging from electronics to composites. Making use of different approaches, unfunctionalized and non-oxidized graphene sheets can be produced; among them an inexpensive and scalable method based on liquid-phase exfoliation of graphite (LPE) holds potential for applications in opto-electronics and nanocomposites. Here we have used n-octylbenzene molecules as graphene dispersion-stabilizing agents during the graphite LPE process. We have demonstrated that by tuning the ratio between organic solvents such as N-methyl-2-pyrrolidinone or ortho-dichlorobenzene, and n-octylbenzene molecules, the concentration of exfoliated graphene can be enhanced by 230% as a result of the high affinity of the latter molecules for the basal plane of graphene. The LPE processed graphene dispersions were further deposited onto solid substrates by exploiting a new deposition technique called spin-controlled drop casting, which was shown to produce uniform highly conductive and transparent graphene films.
authors.affiliation: ISIS &icFRC, Université de Strasbourg &CNRS, 8 allée Gaspard Monge, 67000 Strasbourg, France.
authors.forename: Sébastien
authors.initials: S
authors.lastname: Haar
authors.affiliation: ISIS &icFRC, Université de Strasbourg &CNRS, 8 allée Gaspard Monge, 67000 Strasbourg, France.
authors.forename: Mirella
authors.initials: M
authors.lastname: El Gemayel
authors.affiliation: School of Chemistry, Oxford Road, University of Manchester, Manchester M13 9PL, United Kingdom.
authors.forename: Yuyoung
authors.initials: Y
authors.lastname: Shin
authors.affiliation: Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), UMR 7504, 23 rue du Loess, 67037 Cédex 08 Strasbourg, France.
authors.forename: Georgian
authors.initials: G
authors.lastname: Melinte
authors.affiliation: ISIS &icFRC, Université de Strasbourg &CNRS, 8 allée Gaspard Monge, 67000 Strasbourg, France.
authors.forename: Marco A
authors.initials: MA
authors.lastname: Squillaci
authors.affiliation: Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), UMR 7504, 23 rue du Loess, 67037 Cédex 08 Strasbourg, France.
authors.forename: Ovidiu
authors.initials: O
authors.lastname: Ersen
authors.affiliation: School of Chemistry, Oxford Road, University of Manchester, Manchester M13 9PL, United Kingdom.
authors.forename: Cinzia
authors.initials: C
authors.lastname: Casiraghi
authors.affiliation: ISIS &icFRC, Université de Strasbourg &CNRS, 8 allée Gaspard Monge, 67000 Strasbourg, France.
authors.forename: Artur
authors.initials: A
authors.lastname: Ciesielski
authors.affiliation: ISIS &icFRC, Université de Strasbourg &CNRS, 8 allée Gaspard Monge, 67000 Strasbourg, France.
authors.forename: Paolo
authors.initials: P
authors.lastname: Samorì