解析聚合物电解质燃料电池中的催化剂-层质子导电性的方程,基于使用小角度中子散射确定的离子分布
Masashi Harada1, Hiroaki Kadoura1, Shin-Ichi Takata2
1Toyota Central R&D Laboratories, Inc., 41-1 Yokomichi, Nagakute, Aichi 480-1192, Japan.
ACS applied materials & interfaces
|August 31, 2023
概括
提高聚合物电解质燃料电池性能需要了解催化剂层中的质子导电性. 一个新的模型表明,减少薄膜离子体可以提高质子导电和燃料电池效率.
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
- 化学工程是化学工程的重要组成部分.
背景情况:
- 聚合物电解质燃料电池 (PEFC) 通过催化剂层中的氧降解反应产生电力.
- 通过碳支物上的离子体涂层传导质子对于PEFC性能至关重要.
- 碳支类型和离子体分布显著影响质子导电性.
研究的目的:
- 为PEFC催化剂层开发一种新的质子导电性模型.
- 模拟具有不同离子分子含量和碳支类型的催化剂层.
- 了解离子分子分布对质子导电性的影响.
主要方法:
- 开发一种新的质子导电性模型,考虑薄膜离子体.
- 模拟具有不同离子分子数量和碳类型的催化剂层.
- 使用小角度中子散射来检测离子集群的催化剂层的表征.
主要成果:
- 该模型将离子体视为具有抑制质子导电性的薄膜.
- 薄膜离子分子分数显著影响了整体质子导电性.
- 在厚膜离子体中检测到导质子离子集群.
结论:
- 减少薄膜离子体的比例可以提高催化剂层的性能.
- 优化离子体分布和避免导电性抑制是关键.
- 开发的模型有助于模拟和改进PEFC催化剂层.
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