The Nafion-117 membrane used in vanadium redox flow battery (VRFB) is analyzed by X-ray photoelectron spectroscopy (XPS) and nuclear magnetic resonance (NMR) spectroscopy. The XPS study reveals the chemical identity and environment of vanadium cations accumulated at the surface due to their low diffusivity. On the other hand, the 17O NMR spectrum explores the diffused vanadium cation from the bulk part of Nafion and shows the chemical bonding of cation and the host membrane. The 19F NMR shows the basic Nafion structure is not altered due to the presence of diffused vanadium cation. Based on these spectroscopic studies, the chemical environment of diffused vanadium cation in the Nafion membrane is discussed. This study also shed light into the possible cause for the high diffusivity of certain vanadium cations inside the Nafion membranes.
Revised: March 26, 2012 |
Published: January 1, 2011
Citation
Vijayakumar M., B.M. Sivakumar, P. Nachimuthu, B. Schwenzer, S. Kim, Z. Yang, and J. Liu, et al. 2011.Spectroscopic Investigations of the Fouling Process on Nafion Membranes in Vanadium Redox Flow Batteries.Journal of Membrane Science 366, no. 1-2:325-334.PNNL-SA-73754.doi:10.1016/j.memsci.2010.10.018