在离子交换膜燃料电池中的迁移和沉
Aniket Raut1, Haoyan Fang1, Yu-Chung Lin1
1Department of Materials Science and Chemical Engineering, State University of New York at Stony Brook, Stony Brook, NY, 11794, USA.
Angewandte Chemie (International ed. in English)
|July 19, 2023
概括
离子迁移通过破坏膜来降解阳离子交换膜燃料电池 (AEMFCs). 用铁--催化剂取代,通过防止离子捕获,提高了AEMFC的耐用性.
科学领域:
- 电化学 电化学 电化学
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
背景情况:
- 阳离子交换膜燃料电池 (AEMFC) 在发电方面表现有前途,但与质子交换膜燃料电池 (PEMFC) 相比,其耐用性较低.
- 了解降解机制对于推进AEMFC技术至关重要.
研究的目的:
- 调查AEMFCs性能下降的原因.
- 确定离子迁移在AEMFC降解中的作用.
- 探索替代催化剂,以改善AEMFC的稳定性.
主要方法:
- 使用了补充技术:X射线微型计算机断层扫描 (CT),扫描电子显微镜 (SEM) 和能量分散X射线 (EDX) 光谱.
- 分析的基 (Pt/C) 和铁---碳 (FeCo-N-C) 阴极催化剂.
- 在操作条件下检查了离子行为和膜完整性.
主要成果:
- 确定 (Pt) 离子迁移是AEMFC绩效下降的关键因素.
- 在性介质中观察到Pt+2离子形成,导致溶解或膜迁移.
- 在AEM中,Pt离子被带电群捕获,导致膜分解.
- 铁和离子扩散发生在FeCo-N-C催化剂中,但离子迁移到阳极,不会被困在膜中,从而提高稳定性.
结论:
- 离子迁移和随后在离子交换膜内被困是AEMFCs的主要失败机制.
- 用FeCo-N-C催化剂取代Pt/C,通过改变离子迁移路径来缓解膜降解,从而提高AEMFC的耐用性.
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