Redox Properties of a Rhenium Tetrazolato Complex in Room Temperature Ionic Liquids: Assessing the Applicability of the Stokes-Einstein Equation for a Metal Complex in Ionic Liquids
MetadataShow full item record
The redox properties of a rhenium-tetrazolato complex, namely fac-[Re(CO)3(phen)L] (where L is 5-(4'-cyanophenyl)tetrazolate), have been studied by cyclic voltammetry in a range of common room temperature ionic liquids (RTILs) with different anions and cations. In all eight RTILs, one reduction and two oxidation peaks are observed. It is believed that the reduction peak corresponds to ligand reduction and the two oxidation peaks are two one-electron oxidations of the metal from Re(I) to Re(II) and Re(II) to Re(III). The redox potentials of the metal oxidations appear to be unchanged with the solvent; however, the potential for the reduction peak is more negative in RTILs containing the[P14,6,6,6]+ cation, suggesting a stabilization effect of the electrogenerated intermediate with the other RTIL cations studied (imidazolium and pyrrolidinium). Potential step chronoamperometric experiments were used to calculate diffusion coefficients of the complex in RTILs, and it was found that fac-[Re(CO)3(phen)L] diffuses very slowly through the RTIL medium. A plot of diffusion coefficient against the inverse of viscosity of the RTIL solvent showed a linear trend, suggesting that the Stokes-Einstein relationship generally applies for this complex in RTILs, but the coefficient on the denominator is likely to be closer to 4 (the “slip” limit) than 6 (the “stick” limit) when taking into account the hydrodynamic radius.
Showing items related by title, author, creator and subject.
The Electrochemical Reduction of Hydrogen Sulfide on Platinum in Several Room Temperature Ionic LiquidsO'Mahony, A.; Silvester, Debbie; Aldous, L.; Hardacre, C.; Compton, R. (2008)The electrochemical reduction of 1 atm hydrogen sulfide gas (H2S) has been studied at a platinum microelectrode (10 µm diameter) in five room temperature ionic liquids (RTILs): [C2mim][NTf2], [C4mpyrr][NTf2], [C4mim][OTf], ...
Electrochemical studies of hydrogen chloride gas in several room temperature ionic liquids: Mechanism and sensingMurugappan, K.; Silvester, Debbie (2016)The electrochemical behaviour of highly toxic hydrogen chloride (HCl) gas has been investigated in six room temperature ionic liquids (RTILs) containing imidazolium/pyrrolidinium cations and range of anions on a Pt ...
An Electrochemical Study of the Oxidation of Hydrogen at Platinum Electrodes in Several Room Temperature Ionic LiquidsSilvester, Debbie; Aldous, L.; Hardacre, C.; Compton, R. (2007)The electrochemical oxidation of dissolved hydrogen gas has been studied in a range of room-temperature ionic liquids (RTILs), namely [C2mim][NTf2], [C4mim][NTf2], [N6,2,2,2][NTf2], [P14,6,6,6][NTf2], [C4mpyrr]- [NTf2], ...