Abstract
The electrochemistry of thallium was studied in the basic aluminum chloride-l-methyl-3-ethylimidazolium chloride molten salt at 3O°C. In this basic melt system, thallium (III) chloride is complexed as [TlCl6]3- and can be electrochemically reduced to a Tl(I) species. The T1(III)/(I) electrode reaction exhibits slow charge-transfer kinetics with a standard heterogeneous rate constant of 1.82 × 10-7 cm s-1 and a cathodic transfer coefficient of ca. 0.2 in the 44.4/55.6 mole percent (mol %) melt. The formal potential of this redox couple is dependent upon the chloride concentration of the basic melt, suggesting the loss of two chloride ions from [TlCl6]3- coordination sphere during reduction to produce [TlCl4]3-) which could be further reduced to thallium metal. The formal potentials of the Tl(I)/Tl couple in the 44.4/55.6 and 40.0/60.0 mol % melts are -0.965 and -0.900 V, respectively, vs. Al(III)/Al in the 66.7/33.3 mol % melt. The electrodeposition of thallium on both tungsten and nickel electrodes proceeds via instantaneous three-dimensional nucleation.
Original language | English |
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Pages (from-to) | 1196-1201 |
Number of pages | 6 |
Journal | Journal of the Electrochemical Society |
Volume | 145 |
Issue number | 4 |
DOIs | |
Publication status | Published - 1998 Apr |
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Renewable Energy, Sustainability and the Environment
- Surfaces, Coatings and Films
- Electrochemistry
- Materials Chemistry