Abstract
The move toward nonfluorinated hydrocarbon ionomers for fuel cells and electrolyzers is driven by potential restrictions on polyfluoroalkyl substances such as Nafion. This study examines the key limitations of hydrocarbon ionomers through half- and single-cell experiments with model hydrocarbon ionomers. Half-cell tests reveal three major performance barriers: undesirable adsorption, electrochemical oxidation, and low gas permeability. Competitive sulfate adsorption helps counteract ionomer adsorption and oxidation. These findings align with single-cell performance data, which further reveal additional oxygen mass transport limitations likely caused by localized electrode flooding. Together, these findings offer valuable insights to guide the development of high-performance, fluorine-free hydrocarbon ionomers for next-generation fuel cells and electrolyzers.
| Original language | English |
|---|---|
| Pages (from-to) | 2392-2399 |
| Number of pages | 8 |
| Journal | ACS Energy Letters |
| Volume | 10 |
| Issue number | 5 |
| DOIs | |
| State | Published - May 9 2025 |
Funding
The US Department of Energy (US DOE), Office of Energy Efficiency and Renewable Energy (EERE), and Hydrogen and Fuel Cell Technologies Office (HFTO) supported this research through the M2FCT (Million Mile Fuel Cell Truck) Consortium. The synthesis of PNB polymer task was funded as part of the Fast and Cooperative Ion Transporting in Polymer-Based Materials (FaCT) Energy Frontier Research Center supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences at Oak Ridge National Laboratory. Additionally, this work received partial support from Kyungil University’s Professional Research Program and LANL-Toyota Cooperative Research and Development Agreement (CRADA) project (LA-23-C10885.000.000). Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International Inc., for the DOE’s National Nuclear Security Administration, under contract DE-NA0003525.