Transport Properties, Local Coordination, and Thermal Stability of the Water/Diethylmethylammonium Methanesulfonate Binary System
Journal article, 2016

Ammonium based protic ionic liquids are highlighted for their great potential to sustain proton transport in proton exchange membrane (PEM) fuel cells. Yet, there remain questions concerning the effect of water produced by the fuel cell at the cathode side on the performance of the ionic liquid. In this contribution we report the effect of water on the transport properties and the local coordination in the binary system of the protic ionic liquid diethylmethylammonium methanesulfonate ([DEMA][OMs]) and water, employing 1H NMR, Raman, and infrared spectroscopy. We observe that the self-diffusion of cations and anions increases with the water content and that cations and anions diffuse at the same rate at all concentrations investigated. 1H NMR and vibrational spectroscopy, on the other hand, indicate that added water interacts primarily with the anion and slightly affects the ionicity of the ionic liquid. In addition, by investigating the thermal stability of the binary system we find that although [DEMA][OMs] displays a continuous loss of water upon increasing temperature a fraction of water molecules can be retained even above 120 °C, and that the complete loss of water is immediately followed by decomposition, which is observed to occur at about 185 °C.

NMR Spectroscopy

Water

Vibrational Spectroscopy

Protic Ionic Liquid

PEM Fuel Cell

Author

Negin Yaghini

Chalmers, Chemistry and Chemical Engineering, Applied Chemistry, Applied Surface Chemistry

Mounesha Garaga Nagendrachar

Chalmers, Chemistry and Chemical Engineering, Applied Chemistry, Applied Surface Chemistry

Anna Martinelli

Chalmers, Chemistry and Chemical Engineering, Applied Chemistry, Applied Surface Chemistry

Fuel Cells

1615-6846 (ISSN) 1615-6854 (eISSN)

Vol. 16 1 46-54

Driving Forces

Sustainable development

Subject Categories

Physical Chemistry

Chemical Sciences

Areas of Advance

Energy

Materials Science

DOI

10.1002/fuce.201500064

More information

Latest update

3/2/2020 1