含纳样本的X射线光电子光谱分析:物理化学性质的陷,协议和感知
Michael J Dzara1, Kateryna Artyushkova2, Jayson Foster1
1Department of Chemistry, Colorado School of Mines, Golden, Colorado 80401, United States.
概括
射线光电子谱学 (XPS) 可以损害聚合物电解质膜 (PEM) 燃料电池中的纳菲昂等离子体. 一个新的协议最大限度地减少了这种损伤,使催化剂层的可靠分析成为可能.
科学领域:
- 表面科学是一门科学.
- 材料科学是一种材料科学.
- 电化学 电化学 电化学
背景情况:
- X射线光电谱 (XPS) 对于分析聚合物电解质膜 (PEM) 燃料电池和电解剂组件至关重要.
- 在XPS测量过程中,由于离子体材料的不稳定性,鉴定催化剂层 (CLs) 很困难.
- 在XPS分析中,Nafion是一种常见的离子体,显示了降解问题.
研究的目的:
- 在X射线光电子光谱 (XPS) 条件下研究Nafion的稳定性.
- 在XPS测量过程中确定影响Nafion降解的因素.
- 开发和验证一个可靠的XPS分析对含有离子体的材料的协议.
主要方法:
- 在多个XPS仪器和条件中评估Nafion损伤.
- 通过监测硫信号损失来量化离子体降解.
- 开发并测试了一种多点XPS数据采集协议,以尽量减少样品损坏.
- 使用开发的协议分析了薄膜离子体和基于/碳 (Pt/C) 的CL.
主要成果:
- 在几分钟内观察到显著的Nafion降解 (>50%的硫信号损失).
- 降解程度取决于XPS仪器,测量条件和样品特性.
- 开发的协议有效地最大限度地减少了Nafion的损害,从而实现了无文物数据采集.
- 在CLs的光谱变化表明Nafion和催化剂/支持物种之间的电荷转移相互作用.
结论:
- 在XPS期间的纳菲安不稳定性需要仔细的测量协议.
- 开发的多点协议确保了含有离子体的材料的可靠表征.
- 这种方法促进了对PEM设备中的催化剂-离子体接口和结构-处理-性能关系的基础研究.
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