层间间距对氧化演化反应的二层氧化物催化剂活性的影响
Qing Kang1,2, Loranne Vernisse1,2, Richard C Remsing1,2,3
1Department of Chemistry, Temple University , Beury Hall, 1901 North 13th Street, Philadelphia, Pennsylvania 19122, United States.
Journal of the American Chemical Society
|January 14, 2017
概括
层叠的氧化纳米结构中的金属离子调整了层间间距,显著影响了氧化演化反应 (OER) 的电催化活性. 像这样的较大的离子会提高OER的性能.
科学领域:
- 材料科学
- 电化学
- 纳米技术
背景情况:
- 氧化物是有前途的电催化剂.
- 调节层间距对于优化催化活性至关重要.
- 氧化演化反应 (OER) 是能量转化中的一个关键过程.
研究的目的:
- 研究层间距离与OER电催化活性之间的关系.
- 探索氧化物纳米结构中的金属离子的作用.
- 了解层间间距变化的热力学起源.
主要方法:
- 通过birnessite剥离合成层层的氧化纳米片 (NS).
- 两层催化剂的组装与性金属离子 (Li+,Na+,K+,Rb+,Cs+) 进行间接.
- 原子力显微镜 (AFM) 用于高度的确定.
- 用于热力学分析的分子动力学 (MD) 模拟.
- 对OER活性进行电催化测试 (超电位和Tafel斜率).
主要成果:
- 层间间距与性离子大小正相关:NS/Cs+/NS > NS/Rb+/NS > NS/K+/NS > NS/Na+/NS > NS/Li+/NS.
- 随着层间距离的增加,OER的过量潜力 (η) 降低.
- NS/Cs+/NS具有最低的OER超电位 (0.45V) 在1mA/cm2,高于散装birnessite.
- NS/Li+/NS显示了最大的OER过电位 (0.68V).
结论:
- 氧化物二层间的层间距是OER性能的一个关键因素.
- 通过Cs+等较大的阳离子实现了优化层间距离,显著增强了电催化活性.
- 这些纳米级组件在OER中具有独特的结构优势.
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