TY - JOUR
T1 - Physicochemical properties of ammonium-based deep eutectic solvents and their electrochemical evaluation using organometallic reference redox systems
AU - Bahadori, Laleh
AU - Chakrabarti, Mohammed Harun
AU - Mjalli, Farouq Sabri
AU - Alnashef, Inas Muen
AU - Manan, Ninie Suhana Abdul
AU - Hashim, Mohd Ali
N1 - Funding Information:
The authors are grateful for financial support from the High Impact Research Grant ( UM.C/HIR/MOHE/ENG/18 ) in Malaysia and from the National Plan for Science, Technology and Innovation, Saudi Arabia ( 10-ENV1315-02 ). MHC shows gratitude to Professor N.P. Brandon for allowing the use of full facilities in Imperial College London.
PY - 2013
Y1 - 2013
N2 - Seven deep eutectic solvents (DESs) containing ammonium based salts are prepared by means of hydrogen bonding with acid, amine, amide and nitrate based compounds. The major physicochemical properties of the DESs in terms of density, viscosity, electrical conductivity, molar conductivity and pH are investigated prior to ascertaining their electrochemical characteristics by means of cyclic voltammetry and chronoamperometry. Nitrate based DESs exhibit higher conductivities but lower viscosities than other DESs, whereas the amide based DES displays the widest electrochemical potential window. Diffusion coefficient, D, of two organometallic redox couples, Fc/Fc+ (ferrocene/ ferrocenium) and Cc/Cc+(cobaltocene/cobaltocenium) is found to be of the order of 10-9 to 10-8 cm2 s-1 in all studied DESs while the heterogeneous rate constant for electron transfer across the electrode/DES interface is of the order of 10-4 cm s -1. The Stokes-Einstein products of Fc and Cc+ in the DESs have also been determined.
AB - Seven deep eutectic solvents (DESs) containing ammonium based salts are prepared by means of hydrogen bonding with acid, amine, amide and nitrate based compounds. The major physicochemical properties of the DESs in terms of density, viscosity, electrical conductivity, molar conductivity and pH are investigated prior to ascertaining their electrochemical characteristics by means of cyclic voltammetry and chronoamperometry. Nitrate based DESs exhibit higher conductivities but lower viscosities than other DESs, whereas the amide based DES displays the widest electrochemical potential window. Diffusion coefficient, D, of two organometallic redox couples, Fc/Fc+ (ferrocene/ ferrocenium) and Cc/Cc+(cobaltocene/cobaltocenium) is found to be of the order of 10-9 to 10-8 cm2 s-1 in all studied DESs while the heterogeneous rate constant for electron transfer across the electrode/DES interface is of the order of 10-4 cm s -1. The Stokes-Einstein products of Fc and Cc+ in the DESs have also been determined.
KW - Deep eutectic solvents
KW - Electrochemical window
KW - Organometallic reference redox systems
KW - Stokes-Einstein product
KW - Walden plot of DESs
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U2 - 10.1016/j.electacta.2013.09.102
DO - 10.1016/j.electacta.2013.09.102
M3 - Article
AN - SCOPUS:84886108738
SN - 0013-4686
VL - 113
SP - 205
EP - 211
JO - Electrochimica Acta
JF - Electrochimica Acta
ER -