Table of Contents Author Guidelines Submit a Manuscript
International Journal of Analytical Chemistry
Volume 2015, Article ID 106173, 3 pages
http://dx.doi.org/10.1155/2015/106173
Research Article

Fast Measurement of Methanol Concentration in Ionic Liquids by Potential Step Method

Department of Chemistry, University of Wisconsin Oshkosh, 800 Algoma Boulevard, Oshkosh, WI 54901, USA

Received 26 September 2014; Revised 30 December 2014; Accepted 17 January 2015

Academic Editor: Shi-Gang Sun

Copyright © 2015 Michael L. Hainstock and Yijun Tang. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

The development of direct methanol fuel cells required the attention to the electrolyte. A good electrolyte should not only be ionic conductive but also be crossover resistant. Ionic liquids could be a promising electrolyte for fuel cells. Monitoring methanol was critical in several locations in a direct methanol fuel cell. Conductivity could be used to monitor the methanol content in ionic liquids. The conductivity of 1-butyl-3-methylimidazolium tetrafluoroborate had a linear relationship with the methanol concentration. However, the conductivity was significantly affected by the moisture or water content in the ionic liquid. On the contrary, potential step could be used in sensing methanol in ionic liquids. This method was not affected by the water content. The sampling current at a properly selected sampling time was proportional to the concentration of methanol in 1-butyl-3-methylimidazolium tetrafluoroborate. The linearity still stood even when there was 2.4 M water present in the ionic liquid.