title: Effect of cation structure on the oxygen solubility and diffusivity in a range of bis{(trifluoromethyl)sulfonyl}imide anion based ionic liquids for lithium-air battery electrolytes.
abstract: This paper reports on the solubility and diffusivity of dissolved oxygen in a series of ionic liquids (ILs) based on the bis{(trifluoromethyl)sulfonyl}imide anion with a range of related alkyl and ether functionalised cyclic alkylammonium cations. Cyclic voltammetry has been used to observe the reduction of oxygen in ILs at a microdisk electrode and chronoamperometric measurements have then been applied to simultaneously determine both the concentration and the diffusion coefficient of oxygen in different ILs. The viscosity of the ILs and the calculated molar volume and free volume are also reported. It is found that, within this class of ILs, the oxygen diffusivity generally increases with decreasing viscosity of the neat IL. An inverse relationship between oxygen solubility and IL free volume is reported for the two IL families implying that oxygen is not simply occupying the available empty space. In addition, it is reported that the introduction of an ether-group into the IL cation structure promotes the diffusivity of dissolved oxygen but reduces the solubility of the gas.
authors.affiliation: The School of Chemistry and Chemical Engineering, Queen's University of Belfast, Stranmillis Road, Belfast BT9 5AG, UK. johan.jacquemin@qub.ac.uk c.hardacre@qub.ac.uk.
authors.forename: Alex R
authors.initials: AR
authors.lastname: Neale
authors.affiliation: Department of Chemistry, Physical and Theoretical Chemistry Laboratory, Oxford University, South Parks Road, Oxford OX1 3QZ, UK. richard.compton@chem.ox.ac.uk.
authors.forename: Peilin
authors.initials: P
authors.lastname: Li
authors.affiliation: The School of Chemistry and Chemical Engineering, Queen's University of Belfast, Stranmillis Road, Belfast BT9 5AG, UK. johan.jacquemin@qub.ac.uk c.hardacre@qub.ac.uk.
authors.forename: Johan
authors.initials: J
authors.lastname: Jacquemin
authors.affiliation: The School of Chemistry and Chemical Engineering, Queen's University of Belfast, Stranmillis Road, Belfast BT9 5AG, UK. johan.jacquemin@qub.ac.uk c.hardacre@qub.ac.uk.
authors.forename: Peter
authors.initials: P
authors.lastname: Goodrich
authors.affiliation: Johnson Matthey Technology Centre, Blounts Court, Sonning Common, Reading, RG4 9NH, UK.
authors.forename: Sarah C
authors.initials: SC
authors.lastname: Ball
authors.affiliation: Department of Chemistry, Physical and Theoretical Chemistry Laboratory, Oxford University, South Parks Road, Oxford OX1 3QZ, UK. richard.compton@chem.ox.ac.uk.
authors.forename: Richard G
authors.initials: RG
authors.lastname: Compton
authors.affiliation: The School of Chemistry and Chemical Engineering, Queen's University of Belfast, Stranmillis Road, Belfast BT9 5AG, UK. johan.jacquemin@qub.ac.uk c.hardacre@qub.ac.uk.
authors.forename: Christopher
authors.initials: C
authors.lastname: Hardacre