在电催化条件下高合金的稳定性
Attila Kormányos1,2, Qi Dong3, Bin Xiao4
1Forschungszentrum Jülich GmbH, Helmholtz Institute Erlangen-Nürnberg for Renewable Energy (IEK-11), Cauerstraße 1, 91058 Erlangen, Germany.
iScience
|September 22, 2023
概括
高合金在电催化过程中表现出有限的稳定性改善. 溶解动力学,而不是热力学,可能解释了这些先进材料中观察到的效应.
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
- 物理化学 物理化学
背景情况:
- 建议高合金 (HEAs) 提供增强的稳定性.
- 这种稳定性通常归因于热力学贡献.
- 然而,实验验证,特别是在电催化条件下,是有限的.
研究的目的:
- 为了研究作为电催化剂使用的高热电的溶解行为.
- 评估热力学与动力学影响对合金稳定性的影响.
- 分析各种组成和电化学环境中的溶解.
主要方法:
- 合成的元素 (Pt) 到 (PtRuIrRhPd) 合金样本作为薄膜和纳米粒子.
- 使用在线感应合等离子体质谱 (ICP-MS) 进行溶解分析.
- 在广泛的潜在窗口中,在酸性和性介质中测试了电催化剂.
主要成果:
- 在性条件下,在高酸盐中观察到某些金属的较低溶解.
- 观察到的改善并不显著,并归因于元素度降低.
- 电催化过程中的动力学效应被发现占据了热力学贡献的优势.
结论:
- 高热在电催化过程中所谓的热力学稳定性优势值得怀疑.
- 溶解动力学起着至关重要的作用,往往掩盖了热力学预测.
- 未来的研究应该专注于设计稳定的HEA电催化剂的动力因素.
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