The Effect of Temperature on Kinetics and Diffusion Coefficients of Metallocene Derivatives in Polyol-Based Deep Eutectic Solvents

Laleh Bahadori; Mohammed Harun Chakrabarti; Ninie Suhana Abdul Manan; Mohd Ali Hashim; Farouq Sabri Mjalli; Inas Muen AlNashef; Nigel Brandon

doi:10.1371/journal.pone.0144235

The Effect of Temperature on Kinetics and Diffusion Coefficients of Metallocene Derivatives in Polyol-Based Deep Eutectic Solvents

PLoS One. 2015 Dec 7;10(12):e0144235. doi: 10.1371/journal.pone.0144235. eCollection 2015.

Authors

Laleh Bahadori¹, Mohammed Harun Chakrabarti², Ninie Suhana Abdul Manan³, Mohd Ali Hashim¹, Farouq Sabri Mjalli⁴, Inas Muen AlNashef⁵, Nigel Brandon²

Affiliations

¹ Department of Chemical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur, 50603, Malaysia.
² Department of Earth Science and Engineering, Imperial College London, South Kensington, London, SW7 2AZ, United Kingdom.
³ Department of Chemistry, Faculty of Science, University of Malaya, Kuala Lumpur, 50603, Malaysia.
⁴ Petroleum & Chemical Engineering Department, Sultan Qaboos University, Muscat, 123, Oman.
⁵ Department of Chemical and Environmental Engineering, Masdar Institute of Science and Technology, Abu Dhabi, PO Box 54224, United Arab Emirates.

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.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Electrochemical Techniques*
Kinetics
Models, Chemical*
Solvents / chemistry*

Substances

Solvents

Grants and funding

The University of Malaya and the Ministry of Higher Education funded this work by means of research grant UM.C/HIR/MOHE/ENG/18. The funder’s website is http://hir.um.edu.my/. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.