KES10-0365
Using Simulations to Relate Morphology and Dynamics in Hydrated Ion-Conducting Polymers
Topic
S10. AI-assisted Design and Simulation of Polymers
When and Where
Sep 30, 2026
10:20 - 10:45
Room 109
Session Chairs
Charles SING
Presenter(s)
Amalie Frischknecht (Sandia National Laboratories)
Co-Author(s)
Abstract
There is a need for new fluorine-free polymers for proton and anion-exchange membranes in various electrochemical devices including fuel cells. Achieving high conductivity in hydrated, ion-conducting polymers typically requires the hydrophobic backbone of the polymers to be nanophase separated from the hydrophilic domains so that the ions (protons or hydroxide ions) have well-defined water domains for efficient transport. The ion and water transport thus depends strongly on the hydration level and on the detailed morphology of the hydrophilic domains. Atomistic molecular dynamics (MD) simulations are well-suited to understanding the molecular-level relations between morphology and dynamics. I will discuss our recent simulations of both anionic and cationic all-hydrocarbon polymers that conduct protons or Na+ ions and hydroxide or Cl- ions, respectively. Comparisons will be made to experiments on the same systems, especially X-ray scattering and conductivity. For both classes of polymers, the morphologies of the hydrophilic domains can be characterized through their water channel width distributions, surface areas, and signatures in simulated X-ray scattering intensities. Water and ion diffusivities calculated from the MD simulations are consistent with changes in the nanoscale morphology with changing water content. Interestingly, the water content is a larger determinant of water diffusivity than the ion exchange capacity (IEC) of the polymers.
This work was performed, in part, at the Center for Integrated Nanotechnologies, an Office of Science User Facility operated for the U.S. Department of Energy (DOE) Office of Science. Sandia National Laboratories is a multimission laboratory managed and operated by National Technology & Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International, Inc., for the U.S. DOE’s National Nuclear Security Administration under contract DE-NA-0003525.
This work was performed, in part, at the Center for Integrated Nanotechnologies, an Office of Science User Facility operated for the U.S. Department of Energy (DOE) Office of Science. Sandia National Laboratories is a multimission laboratory managed and operated by National Technology & Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International, Inc., for the U.S. DOE’s National Nuclear Security Administration under contract DE-NA-0003525.
