State of water in nafion 117 proton exchange membranes studied by dielectric relaxation spectroscopy

Georgios Polizos, Zijie Lu, Digby D. Macdonald, Evangelos Manias

Research output: Chapter in Book/Report/Conference proceedingConference contribution

2 Scopus citations


The dynamics and the nature of water environments in a fuel cell proton exchange membrane are studied experimentally. Specifically, the dynamics of water in Nafion 117 membranes, in the acid form, were investigated at two hydration levels and several temperatures by means of dielectric relaxation spectroscopy; two different dielectric spectroscopy experimental setups were employed for low (10-2-107 Hz, 25 to -80°C) and microwave (0.045-26 GHz, 35°C) frequency ranges. Three states of water were clearly identified: (a) water strongly bound to the sulfonic groups (in quantitative agreement with previous investigations) defining the first hydration layer; (b) loosely bound water, surrounding the first layer, and (c) free water, having similar dynamics as in the bulk/liquid water. This is the first time that the dynamics of loosely bound water are experimentally observed.

Original languageEnglish (US)
Title of host publicationSolid-State Ionics-2006
Number of pages6
StatePublished - 2007
Event2006 MRS Fall Meeting - Boston, MA, United States
Duration: Nov 27 2006Dec 1 2006

Publication series

NameMaterials Research Society Symposium Proceedings
ISSN (Print)0272-9172


Other2006 MRS Fall Meeting
Country/TerritoryUnited States
CityBoston, MA

All Science Journal Classification (ASJC) codes

  • General Materials Science
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering


Dive into the research topics of 'State of water in nafion 117 proton exchange membranes studied by dielectric relaxation spectroscopy'. Together they form a unique fingerprint.

Cite this