title: The Effect of Temperature on Kinetics and Diffusion Coefficients of Metallocene Derivatives in Polyol-Based Deep Eutectic Solvents.
abstract: The temperature dependence of the density, dynamic viscosity and ionic conductivity of several deep eutectic solvents (DESs) containing ammonium-based salts and hydrogen bond donvnors (polyol type) are investigated. The temperature-dependent electrolyte viscosity as a function of molar conductivity is correlated by means of Walden's rule. The oxidation of ferrocene (Fc/Fc+) and reduction of cobaltocenium (Cc+/Cc) at different temperatures are studied by cyclic voltammetry and potential-step chronoamperometry in DESs. For most DESs, chronoamperometric transients are demonstrated to fit an Arrhenius-type relation to give activation energies for the diffusion of redox couples at different temperatures. The temperature dependence of the measured conductivities of DES1 and DES2 are better correlated with the Vogel-Tamman-Fulcher equation. The kinetics of the Fc/Fc+ and Cc+/Cc electrochemical systems have been investigated over a temperature range from 298 to 338 K. The heterogeneous electron transfer rate constant is then calculated at different temperatures by means of a logarithmic analysis. The glycerol-based DES (DES5) appears suitable for further testing in electrochemical energy storage devices.
authors.affiliation: Department of Chemical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur, 50603, Malaysia.
authors.forename: Laleh
authors.initials: L
authors.lastname: Bahadori
authors.affiliation: Department of Earth Science and Engineering, Imperial College London, South Kensington, London, SW7 2AZ, United Kingdom.
authors.forename: Mohammed Harun
authors.initials: MH
authors.lastname: Chakrabarti
authors.affiliation: Department of Chemistry, Faculty of Science, University of Malaya, Kuala Lumpur, 50603, Malaysia.
authors.forename: Ninie Suhana Abdul
authors.initials: NS
authors.lastname: Manan
authors.affiliation: Department of Chemical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur, 50603, Malaysia.
authors.forename: Mohd Ali
authors.initials: MA
authors.lastname: Hashim
authors.affiliation: Petroleum & Chemical Engineering Department, Sultan Qaboos University, Muscat, 123, Oman.
authors.forename: Farouq Sabri
authors.initials: FS
authors.lastname: Mjalli
authors.affiliation: Department of Chemical and Environmental Engineering, Masdar Institute of Science and Technology, Abu Dhabi, PO Box 54224, United Arab Emirates.
authors.forename: Inas Muen
authors.initials: IM
authors.lastname: AlNashef
authors.affiliation: Department of Earth Science and Engineering, Imperial College London, South Kensington, London, SW7 2AZ, United Kingdom.
authors.forename: Nigel
authors.initials: N
authors.lastname: Brandon
mesh_terms: D055664:Electrochemical Techniques; D007700:Kinetics; D008956:Models, Chemical; D012997:Solvents / Q000737:chemistry*
chemical_list: D012997:Solvents