调节Co-O共价性来操纵机械转换,以提高酸性水氧化中的活性/耐久性
Jiachen Zhang1, Guangbo Chen2,3, Dongmei Sun1
1Jiangsu Key Laboratory of New Power Batteries, Jiangsu Collaborative Innovation Center of Biomedical Functional Materials, School of Chemistry and Materials Science, Nanjing Normal University 210023 Nanjing China hanjun.sun@njnu.edu.cn.
Chemical science
|October 14, 2024
概括
研究人员开发了地球上大量的电催化剂,用于生产气. 通过将 (Ru) 替换为氧化物 (Co3O4),他们提高了酸氧演化反应 (OER) 的活性和耐久性.
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
- 催化剂是一种催化剂.
背景情况:
- 开发用于酸氧演化反应 (OER) 的地球丰富的电催化剂对于高效的 (H2) 生产至关重要.
- 在这些催化剂中同时实现高活性和长期耐用性,特别是在酸性介质中,是一个重大的科学挑战.
研究的目的:
- 为了克服催化活性和可氧化物 (Co3O4) 基电催化剂中酸性OER的动态耐久性之间的权衡.
- 通过将 (Ru) 单原子位 (SAs) 纳入Co3O4结构来设计和合成新型电催化剂.
主要方法:
- 理论计算,包括密度函数理论 (DFT),用于指导催化剂设计.
- 在现场表征技术被用来探测反应条件下的催化剂的行为.
- 进行了电化学测量,以评估OER活性和在酸性介质中的耐用性.
主要成果:
- 在Co3O4的四面体 (Td) 位点实现了Ru替代CO2+的优先替代.
- 引入Ru SAs增强了Co-O共价性,促进了基 (OH*) 物种的生成,并稳定了催化剂结构.
- 设计的Ru SAs-Co3O4催化剂在酸性介质中表现出优越的OER活性 (10mA cm-2的超电位188mV) 和耐用性,与现有的Co3O4和Ru基催化剂相比.
结论:
- 单原子替代有效地解决了酸性OER中的Co3O4中的活性-耐久性平衡.
- 增强的Co-O共价性和稳定结构是提高催化性能的关键.
- 这种方法为开发用于可持续生产的先进电催化剂提供了一个有希望的战略.
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