Video-STM studies of adsorbate dynamics at electrochemical interfaces

电化学界面吸附物动力学的视频 STM 研究

• 批准号: 111205716
• 负责人: Professor Dr. Olaf Magnussen
• 金额: --
• 依托单位: Department of Chemistry
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2009
• 资助国家: 德国
• 起止时间: 2008-12-31 至 2015-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/111205716?language=en
• 关键词: Video; STM; studies; adsorbate; dynamics

In this project the dynamic behavior of individual adsorbates at electrochemical interfaces will be studied systematically by in situ high-speed scanning tunneling microscopy (Video-STM). These measurements will be performed as a function of potential and temperature for different anionic (S, I, CN) and cationic (Pb, Te, vacancies) adsorbates on Cu(100) and Ag(100) electrode surfaces. The atomic-scale adsorbate motion will be directly monitored by time-resolved STM. Based on an extensive statistical analysis of these data quantitative results on surface diffusion and adsorbate-adsorbate interactions will be obtained. In particular, the role of coadsorbed species (Cl, Br, sulfate) and potential on the adsorbate dynamics will be investigated, to (i) elucidate the origin of the pronounced potential dependence of the surface transport processes, found in our pioneering studies on Sad diffusion on Cu(100) in HCl solution, and to (ii) determine how coadsorbates, which are ubiquitously present in electrochemical environment, influence the diffusion barriers and interaction energies. This project will be complemented by a parallel application for a project, in which thermodynamic and kinetic electrochemical data on these adsorbate systems will be obtained in parallel. In total, these direct microscopic and complementary electrochemical studies should provide fundamental insights into the effect of the electrochemical environment on the diffusion and interaction of adsorbed species – a central elementary step in many electrode reactions.

在该项目中，将通过原位高速扫描隧道显微镜（Video-STM）系统地研究电化学界面处单个吸附物的动态行为。这些测量将根据 Cu(100) 和 Ag(100) 电极表面上不同阴离子（S、I、CN）和阳离子（Pb、Te、空位）吸附物的电势和温度进行。原子级吸附物运动将由时间分辨 STM 直接监测。基于对这些数据的广泛统计分析，将获得表面扩散和吸附物-吸附物相互作用的定量结果。特别是，将研究共吸附物质（Cl、Br、硫酸盐）和电势对吸附物动力学的作用，以（i）阐明表面传输过程的明显电势依赖性的起源，这在我们对 HCl 溶液中 Cu（100）上的 Sad 扩散的开创性研究中发现，并（ii）确定电化学环境中普遍存在的共吸附物如何影响 扩散势垒和相互作用能。该项目将得到一个项目的并行应用的补充，其中将并行获得这些吸附物系统的热力学和动力学电化学数据。总的来说，这些直接的微观和互补的电化学研究应该为电化学环境对吸附物质的扩散和相互作用的影响提供基本的见解——这是许多电极反应的核心基本步骤。