在PEM水电解中的阴极催化剂层设计,以减少Pt负荷和交叉
Zheyu Zhang1, Axelle Baudy1, Andrea Testino2,3
1Electrochemistry Laboratory, Paul Scherrer Institut, 5232 Villigen PSI, Switzerland.
ACS applied materials & interfaces
|April 23, 2024
概括
优化具有低负载 (0.025 mgPt/cm2) 的质子交换膜 (PEM) 电解器阴极是关键. 一个特定的正极结构使用40%的Pt在高表面积碳和0.35的离子体与碳的比率最大限度地减少交叉.
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
- 可持续能源技术 可持续能源技术
背景情况:
- 减少类金属的使用对于广泛的质子交换膜 (PEM) 水电解至关重要.
- 研究往往忽视了阴极催化剂层优化和 (Pt) 负载减少,而是专注于阳极.
- 阴极结构设计对于最大限度地减少 (H2) 交叉至关重要,特别是在薄膜 (50μm) 中.
研究的目的:
- 调查阴极结构参数,以减少Pt负载到0.025 mgPt/cm2.
- 为了尽量减少PEM水电解系统中的交叉速率.
- 了解Pt wt %,碳支类型和离子体含量对性能和交叉的影响.
主要方法:
- 详细研究了阴极结构参数:Pt重量% (Pt/C电催化剂),碳支类型 (Vulcan与HSAC) 和离子体含量.
- 分析电化学性能,重点关注接口接触电阻和阴极厚度.
- 在阳极出口测量H2中的O2以量化交叉.
- 交叉速率与局部体积电流密度和质量转移系数的相关性.
主要成果:
- 电化学性能受到由于阴极厚度导致的接口接触电阻变化的显著影响.
- 较高的Pt重量%和离子体含量与增加的H2交叉 (H2在O2%) 有正相关.
- 下Pt负荷显示与测量H2交叉的反向关系.
- 确定了一种最佳的阴极配置:在HSAC支上40 wt % Pt,离子体与碳 (I/C) 的比率为0.35.
结论:
- 优化的阴极结构 (40% Pt/HSAC,I/C比为0.35) 实现了0.025 mgPt/cm2的低Pt负荷.
- 这种配置有效地降低了PEM水电解中的交叉速率.
- 战略性阴极设计对于平衡低利用率和高效的管理至关重要.
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