The nanostructure and ion dynamics of novel hydrocarbon ionene AEMs via scattering and simulation

*To request access to the videoconference, email dsivak@sfu.ca

Perfluorinated sulfonic acid-based (PFSA) ionomers currently dominate the fuel cell industry. However, the hostility to catalyst material, difficult and expensive synthetic routes, and environmental concerns of PFSA materials present major challenges to wider adoption of fuel cell technology. Hydrocarbon-based membranes utilize simple, well-developed synthetic routes that allow for rapid material development. We have investigated a promising series of fully aromatic hydrocarbon ionene anion-exchange membranes (AEMs) utilizing a combination of X-ray scattering and molecular dynamics simulations to elucidate the morphology of these materials and have utilized molecular dynamics to investigate the role of cation and polymer architecture in ion transport dynamics. Backbone architecture appears to play a limited role in determining conductivity at constant hydration number.

[1] Andrew G. Wright, and Steven Holdcroft. "Hydroxide-stable ionenes." ACS Macro Letters 3.5 (2014): 444-447.

[2] Eric M. Schibli,  et al. "The Nanostructure of HMT-PMBI, a Sterically Hindered Ionene." Macromolecules. 53.12 (2020): 4908-4916.

[3] Jiantao Fan,  et al.  "Poly (bis-arylimidazoliums) possessing high hydroxide ion exchange capacity and high alkaline stability." Nature Communications. 10.1 (2019): 1-10.

[4] Phillip Overton, et al. “Tuning Ion Exchange Capacity in Hydroxide-Stable Poly(arylimidazolium) Ionenes: Increasing the Ionic Content Decreases the Dependence of Conductivity and Hydration on Temperature and Humidity.  Macromolecules. (2020): Accepted.