Modeling of polymer membrane nanostructure and its effect on proton and small molecule transport
EMSL Project ID
24811
Abstract
Polymer electrolyte membrane fuel cells are a crucial part of the hydrogen economy. A barrier to their commercial viability is the lack of fundamental molecular-level understanding of membrane nanostructure, proton transfer at the hydrophilic interface, proton hopping, electro-osmotic drag of small molecules, and membrane dynamics. We propose rational material selection for fuel cell electrolytes based on multiscale modeling validated by available experimental data. Due to the multiple time and length scales associated with this problem, we will employ a hierarchical modeling approach from ab initio electronic structure calculations of proton transfer to mesoscopic modeling of the membrane dynamics. The simulations will be linked together using a parameter passing approach. Our study will focus on perfluoro-sulfonic acid membranes and will examine the effect of varying the side chain length and separation between side chains on proton transfer from the sulfonic acid to water molecules, proton transport, clustering of water molecules, and membrane dynamics. This study will provide insights into proton transport at low hydration and membrane degradation upon prolonged operation, and is in support of the Hydrogen Fuel Initiative.
Project Details
Project type
Large-Scale EMSL Research
Start Date
2007-05-22
End Date
2010-09-30
Status
Closed
Released Data Link
Team
Principal Investigator
Team Members