Oxygen- and proton-transporting open framework ionomer for medium-temperature fuel cells

• 成果类型: Article
• 署名作者: Yang, Jianwei; Xu, Hengyu; Li, Jie; Gong, Ke; Yue, Feiyu; Han, Xianghao; Wu, Ke; Shao, Pengpeng; Fu, Qingling; Zhu, Yuhao; Xu, Wenli; Huang, Xin; Xie, Jing; Wang, Fengchao; Yang, Wenxiu; Zhang, Teng; Xu, Zengshi; Feng, Xiao; Wang, Bo
• 署名单位: Beijing Institute of Technology; Chinese Academy of Sciences; University of Science & Technology of China, CAS
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-10568
• DOI: 10.1126/science.adq2259
• 发表日期: 2024-09-06
• 页码: 1115-1120
• 关键词: metal-organic framework; reduction reaction; catalyst layers; performance; crystalline; resistance; DYNAMICS; insights; range

摘要

Medium-temperature proton exchange membrane fuel cells (MT PEMFCs) operating at 100 degrees to 120 degrees C have improved kinetics, simplified thermal and water management, and broadened fuel tolerance compared with low-temperature PEMFCs. However, high temperatures lead to Nafion ionomer dehydration and exacerbate gas transportation limitations. Inspired by osmolytes found in hyperthermophiles, we developed alpha-aminoketone-linked covalent organic framework (COF) ionomers, interwoven with Nafion, to act as breathable proton conductors. This approach leverages synergistic hydrogen bonding to retain water, enhancing hydration and proton transport while reducing oxygen transport resistance. For commercial Pt/C, the MT PEMFCs achieved peak and rated power densities of 18.1 and 9.5 Watts per milligram of Pt at the cathode at 105 degrees C fueled with H-2 and air, marking increases of 101 and 187%, respectively, compared with cells lacking the COF.