在聚合物电解质膜燃料电池中,在Pt表面上的潜在依赖性离子体重新排列
Dong Wook Lee1, Jonghyun Hyun1, Euntaek Oh1
1Department of Chemical & Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea.
ACS applied materials & interfaces
|January 22, 2024
概括
在聚合物电解质膜燃料电池 (PEMFC) 中, (Pt) 表面的潜在变化会改变离子体如何粘附于催化剂. 这种离子体重新排列可以降低燃料电池的性能和耐用性.
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
- 化学工程是化学工程的重要组成部分.
背景情况:
- 催化剂-离子体接口对于聚合物电解质膜燃料电池 (PEMFC) 的性能和耐用性至关重要.
- 由于催化剂层的复杂结构,理解界面变化是具有挑战性的.
研究的目的:
- 在不同潜力下研究纳米粒子界面Nafion-Pt的动态变化.
- 阐明这些界面变化对PEMFC耐用性和性能的影响.
主要方法:
- 使用块共聚合物模板制造Pt纳米粒子 (NP) 阵列电极.
- 对受到各种恒定电位的电极进行分析,以观察界面变化.
- 评估离子体吸附,包装密度和氧气运输阻力.
主要成果:
- 由于Pt表面的正电荷增加,纳薄膜在中间电位 (0.4和0.7V) 呈现密集的包装.
- 中间电位保持导致较大的离子体吸附到Pt表面.
- 增加的离子体吸附会导致更高的氧气运输阻力,从而对功率性能产生负面影响.
结论:
- 在催化剂-离子体接口上的潜在依赖性离子体重组是PEMFC性能降低的关键机制.
- 控制潜力保持可以减轻有害的离子体吸附和改善燃料电池的耐用性.
- 这项研究为改善未来设计提供了对PEMFC降解机制的关键见解.
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