关于在酸性介质中氧气演变反应期间氧化物的操作结构
Nipon Deka1, Travis E Jones2, Lorenz J Falling3
1Leiden Institute of Chemistry, Leiden University, 2300 RA Leiden, The Netherlands.
概括
氧化催化剂在氧化演化反应 (OER) 条件下发生转化. 这项研究揭示了氧格子激活,特别是在无形氧化物中,驱动高活性,但降低稳定性.
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
- 催化剂是一种催化剂.
背景情况:
- 氧进化反应 (OER) 催化剂的合理设计需要理解结构-活性-稳定性关系.
- 像氧化 (IrOx) 和氧化 (RuOx) 这样的电催化剂在OER条件下经历结构变化.
- 操作结构,或反应条件下的结构,对于催化剂性能至关重要.
研究的目的:
- 在OER条件下研究无形和晶体氧化的激活过程.
- 为了将结构演变和氧化状态与催化活性和稳定性相关联.
- 阐明表面氧物种和Ru氧化状态在形成活性OER结构中的作用.
主要方法:
- 用X射线吸收光谱 (XAS) 追踪Ru氧化状态的变化.
- 电化学扫描电子显微镜 (EC-SEM) 用于绘制表面物种的地图.
- 在现场进行电化学测量,以研究操作条件.
主要成果:
- 氧化物在OER下经历了表面基基组的显著脱.
- 形成了高度氧化的活性物质,包括Ru原子和氧格子的氧化.
- 无形氧化物表现出特别强烈的氧网格激活.
- 这种格子激活与高的OER活动相关,但稳定性较低.
结论:
- 氧化演化反应 (OER) 的激活包括deprotonation和氧化网的显著氧化.
- 无形氧化物的高活性与其明显的氧格子激活有关.
- 观察到的无形RuOx的高活性和低稳定性归因于这种氧格子激活机制.
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