了解燃料电池中碳化合物 - PFSA离子体导电性差距
William Bangay1,2, Michael Yandrasits1, Wayne Hayes2
1Johnson Matthey Technology Centre, Sonning Common, Reading, UK. william.bangay@matthey.com.
Physical chemistry chemical physics : PCCP
|April 4, 2025
概括
碳化合物离子体对燃料电池来说是有前途的,但在低湿度下导电性较低. 这种导电性差距是由于干聚合物中的质子扩散,而不是水化水平.
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 化学工程是化学工程的重要组成部分.
背景情况:
- perfluorinated sulfonic acid (PFSAs) 是燃料电池和电解器中的标准成分.
- 碳化合物离子体 (HCs) 是 PFSAs 的新兴替代品.
- 电机需要相似的导电能力和寿命才能生存.
研究的目的:
- 研究HC离子体中的"导电性差距".
- 了解限制HC离子体导电性的因素,特别是在低湿度下.
- 将HC离子体性能与PFSA进行比较.
主要方法:
- 检查的离子体导电率与水体积分数相比.
- 将导电率转换为质子扩散率进行分析.
- 将通用有效媒体 (GEM) 理论应用于扩散率数据.
主要成果:
- 在相对湿度 (RH) 低的情况下,HC离子体具有较低的导电性.
- 质子扩散性分析显示,在离子体之间解离时,类似的水合需求.
- 干性聚合物中的质子扩散显著增加了导电性差距.
- 膜扭曲性影响干膜扩散性和低RH导电性.
结论:
- 在HC离子体中的导电性差距主要与干聚合物质子扩散有关.
- 膜结构 (曲率) 对低RH性能至关重要.
- 在高RH时,质子度,而不是扩散,限制了所有离子体的导电性.
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