在电极上形成和扩散地表吸附物
Björn Rahn1, Olaf M Magnussen1
1Institute of Experimental and Applied Physics , Kiel University , Olshausenstrasse 40 , 24098 Kiel , Germany.
Journal of the American Chemical Society
|July 10, 2018
概括
研究人员观察到地下物种在金属电极上形成,并在表面层中迁移. 这一发现使用扫描道显微镜,通过空隙介导途径显示了增强的表面扩散,可能会影响电催化.
科学领域:
- 表面科学
- 电化学
- 材料科学
背景情况:
- 了解金属电极的界面过程对于电催化是至关重要的.
- 电极表面层中的物种动态尚未完全理解.
- 电化学双层会影响表面反应.
研究的目的:
- 在金属电极上直接观察地下物种的形成和迁移.
- 研究表面空缺在物种扩散中的作用.
- 探索增强的表面动力学对电催化反应的影响.
主要方法:
- 在现场视频速率扫描道显微镜 (STM).
- 在液体电解质中的覆盖的Ag100) 电极上研究了吸附硫化物.
- 分析了表面吸附点和地下空隙之间的可逆过渡.
主要成果:
- 在电化学双层下直接观察地下物种的形成和迁移.
- 在表面位置和第一层Ag空隙之间确定了吸附硫化物的可逆过渡.
- 在硫化物表面扩散中观察到的数量级增强归因于空隙介导的途径.
结论:
- 地下物种的形成和迁移是金属电极表面发生的动态过程.
- 空隙介导的扩散显著提高了表面物种的流动性.
- 这些发现表明了电催化反应和物质生长过程的新途径.
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