Molecular mechanisms of proton conduction in polymer electrolyte membranes are addressed by ab initio molecular dynamics calculations, utilizing the VASP program, on the model system trifluoromethane sulfonic acid monohydrate solid. After establishing that the experimental crystal is stably simulated, these computations are used to seek crystal defects that might contribute to proton conduction. The most favorable defect found involves formation of a Zundel ion, H5O2 +, and H-bonded, paired sulfonate groups. The energy of this defect is 0.3-0.4eV above the energy of the undefected solid, in suggestive agreement with the observed activation energy for proton transport in minimally hydrated Nafion®.
Journal: TechConnect Briefs
Volume: 2, Technical Proceedings of the 2002 International Conference on Computational Nanoscience and Nanotechnology
Published: April 22, 2002
Pages: 115 - 116
Industry sectors: Advanced Materials & Manufacturing | Personal & Home Care, Food & Agriculture
Topic: Personal & Home Care, Food & Agriculture