Computational evaluation of hydrogen bonding interactions in watermethanol solvated SPPO membranes

Molecular dynamics (MD) simulation tools were utilized to examine the influences associated with methanol permeation phenomena on hydrogen bond interaction behavior in watermethanol solvated SPPO membrane in terms of radial distribution function (RDF) and number of hydrogen bonds (H-bond). Evaluation of RDF data attained from MD simulations showed that water, methanol, and hydronium ions have hydrogen bond interactions with proton conductive sulfonic acid side groups of SPPO materials with higher number of H-bonds between hydronium ions-sulfonic acid groups. It was found that hydronium ions formed greater number of H-bonds with water molecules compared to methanol solvent indicating solvation of hydronium ions by water molecules. Additionally, H-bond number analyses among solvent molecules demonstrated that methanol molecules are present in aqueous phase in phase-separated structure of SPPO, which suggested that undesired methanol crossover phenomena in direct methanol fuel cells likely occur through solvent phase within the membrane.

کلیدواژه ها:

Fuel cell membrane ، Sulfonated poly(phenylene oxide) (SPPO) ، Methanol crossover ، Molecular dynamics simulation