Zinc Electrodeposition from Deep Eutectic Solvents Seminar
- Time:
- 14:00
- Date:
- 6 October 2014
- Venue:
- Building 27 Room 2003 Chemistry University of Southampton Southampton SO17 1BJ
For more information regarding this seminar, please email Nuria Garcia-Araez at N.Garcia-Araez@soton.ac.uk .
Event details
Dr. Bernhard Gollas presents a seminar as part of the Electrochemistry's seminar series.
Since their discovery some ten years ago, deep eutectic solvents have been advocated as cheap and environmentally benign alternatives to classical room temperature ionic liquids. [1, 2] For a more widespread use of these types of electrolytes in electrochemical applications a better understanding of their interfacial behaviour is required. In our search for hydrogen-free zinc plating we have studied the electrodeposition of zinc from a deep eutectic 1:2 molar mixture of choline chloride and ethylene glycol containing ZnCl2. [3] Unusual electrochemical behaviour has been observed in cyclic voltammetry at static and rotating glassy carbon disc electrodes and in chronoamperometry. Raman spectroscopy confirmed the tetrachlorozincate ion [ZnCl4]2- as the main zinc species in this strongly Lewis-basic electrolyte. We suggested a reaction mechanism that involves the reduction of solvent components under formation of hydrogen. [4]
The study has been extended to Pt, Au, Cu and steel electrodes. The cyclic voltammetric behaviour of the system at these electrode materials indicates that apart from the formation of surface alloys adsorption of electrolyte components also play a role in this electrode reaction. Polarization modulation infrared reflection absorption spectroscopy (PM-IRRAS) [5, 6] has been applied for the first time at glassy carbon electrodes to obtain chemical information on the formation and nature of the adsorbate.
References:
[1] A.P. Abbott, G. Capper, D.L. Davies, R.K. Rasheed, V. Tamyrajah, Chem. Commun. 2003, 70.
[2] F. Endres, D. MacFarlane, A. Abbott (Eds.), Electrodeposition from Ionic Liquids, Wiley-VCH, Weinheim 2008.
[3] A.H. Whitehead, M. Pölzler, B. Gollas, J. Electrochem. Soc. 2010, 157, D328.
[4] L. Vieira, A.H. Whitehead, B. Gollas, J. Electrochem. Soc. 2014, 161, D7.
[5] V. Zamlynny, J. Lipkowski in R.C. Alkire, D.M. Kolb, J. Lipkowski, P.N. Ross (Eds.), Diffraction and Spectroscopic Methods in Electrochemistry, Wiley-VCH, Weinheim 2006, Vol. 9, pp. 315.
[6] R. Schennach, C. Hirschmugl, E. Gilli, W.T. Tysoe, Appl. Spect. 2009, 63 (3) 369.
Speaker information
Dr. Bernhard Gollas, Institute for Chemistry and Technology of Materials, Graz University of Technology, Stremayrgasse 9, 8010 Graz, Austria. After his chemistry studies at the University Tübingen/Germany and the University of Oregon/USA, he received his PhD under the supervision of Bernd Speiser in the fields of organic electrochemistry and modified electrodes at the University Tübingen in 1996. From 1996 until 2000, stay as postdoctoral researcher with Phil Bartlett and Guy Denuault in the Southampton Electrochemistry Group. Construction of an in situ-combination of an electrochemical quartz-crystal microbalance (EQCM) and a scanning electrochemical microscope (SECM), and studies on the templated electrodeposition of mesoporous metal films. Since 2001 Key Scientist in the ECHEM Centre of Competence in Applied Electrochemistry in Wiener Neustadt/Austria and its successor CEST Centre of Competence for Electrochemical Surface Technology. Scientific Spokesperson of CEST from 2009 to 2010. From 2002 Assistant Professor at the Graz University of Technology/Austria. Since 2008 Associate Professor at the Institute for Chemical Technology of Materials at the Graz University of Technology.