Molecular dynamics studies of the Nafion®, Dow® and Aciplex® fuel-cell polymer membrane systems
2007 (English)In: Journal of Molecular Modeling, ISSN 1610-2940, E-ISSN 0948-5023, Vol. 13, no 10, 1039-1046 p.Article in journal (Refereed) Published
The Nafion, Dow and Aciplex systems – where the prime differences lies in the side-chain length – have been studied by molecular dynamics (MD) simulation under standard pressure and temperature conditions for two different levels of hydration: 5 and 15 water molecules per (H)SO3 end-group. Structural features such as water clustering, water-channel dimensions and topology, and the dynamics of the hydronium ions and water molecules have all been analysed in relation to the dynamical properties of the polymer backbone and side-chains. It is generally found that mobility is promoted by a high water content, with the side-chains participating actively in the H3O+/H2O transport mechanism. Nafion, whose side-chain length is intermediate of the three polymers studied, is found to have the most mobile polymer side-chains at the higher level of hydration, suggesting that there could be an optimal side-chain length in these systems. There are also some indications that the water-channel network connectivity is optimal for high water-content Nafion system, and that this could explain why Nafion appears to exhibit the most favourable overall hydronium/water mobility.
Place, publisher, year, edition, pages
2007. Vol. 13, no 10, 1039-1046 p.
Molecular dynamics, Nafion membrane, Proton exchange membrane fuel cell (PEMFC), Side-chain length
IdentifiersURN: urn:nbn:se:uu:diva-13970DOI: 10.1007/s00894-007-0230-7ISI: 000248912300002PubMedID: 17665227OAI: oai:DiVA.org:uu-13970DiVA: diva2:41740