Characterization of Electrode Activity through Photoelectron Spectroscopy: A Coordinated Synchrotron and Laboratory XPS Approach to Electrocatalysis

通过光电子能谱表征电极活性：协调同步加速器和实验室 XPS 电催化方法

• 批准号: 0651083
• 负责人: Andrzej Wieckowski
• 金额: $ 61.06万
• 依托单位: University of Illinois at Urbana-Champaign
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-06-01 至 2012-02-29
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0651083&HistoricalAwards=false
• 关键词: Characterization; Electrode; Activity; through; Photoelectron

This project, funded by the Analytical and Surface Chemistry Program, addresses the correlation between core level electron binding energy shifts and electrocatalytic reactivity at binary and ternary electrode catalysts for small molecule oxidation/reduction reactions. The catalysts are formed by spontaneous deposition of transition metals on single crystal substrates of Pt, Ru, Pd and Au. There is strong evidence that the admetals are arranged in two- and three-dimensional nanoislands, as monitored by in situ STM. This work is carried out in the laboratory of Andrzej Wieckowski at the University of Illinois and at the Synchrotron Radiation Center (SRC) at the University of Wisconsin-Madison; the intense synchrotron x-ray light is needed to measure the binding energy shifts at the low and very low admetal coverage levels. Moreover, the high resolution of the synchrotron radiation makes possible accurate measurements of the binding energy shifts. A strong and direct link between experiment (Wieckowski UIUC, PI) and theory (Bagus UNT, co-PI) is a key element of this project that basically determines the chemical and physical significance of the measured core level binding energies. The synchrotron work brings high x-ray intensity, high resolution, and low detection level for the admetal coverage. Overall: electrochemical characterization determines reactivity, synchrotron XPS and laboratory XPS yield the binding energy shifts, and theory provides quantitative link between the reactivity and electronic structure of the studied surfaces. These electronic-level results produce understanding of how transition and noble metal bimetallic catalysts work for electrocatalytic reactions of clear basic-science and applied significance. The materials studied show promise as effective oxidation and reduction catalysts in small molecule fuel cell applications. Therefore, information obtained from these fundamental investigations may aid in the design of improved fuel cell catalytic systems.

该项目由分析和表面化学计划资助，解决了小分子氧化/还原反应的二元和三元电极催化剂在二元和三元电极催化剂上的核心水平电子结合能量与电催化反应之间的相关性。催化剂是由在Pt，Ru，Pd和Au的单晶基板上自发沉积过渡金属形成的。 有强有力的证据表明，正如原位STM所监测的那样，这些副群是在两维纳米群岛中排列的。这项工作是在伊利诺伊大学的安德烈·威克斯基（Andrzej Wieckowski）的实验室以及威斯康星大学 - 麦迪逊分校的同步辐射中心（SRC）的。需要强烈的同步加速器X射线灯来测量低和非常低的额叶覆盖水平的结合能移动。 此外，同步加速器辐射的高分辨率使结合能移动的准确测量可能。实验（Wieckowski uiuc，pi）和理论（Bagus unt，co-Pi）之间的紧密而直接的联系是该项目的关键要素，它基本上决定了测得的核心水平结合能的化学和物理意义。 同步加速器的工作带来高X射线强度，高分辨率和低检测水平的副覆盖范围。总体而言：电化学表征决定了反应性，同步加速器XPS和实验室XPS产生结合能移位，理论提供了研究表面的反应性和电子结构之间的定量联系。 这些电子级别的结果产生了对过渡和贵金金属双金属催化剂如何用于清晰基本科学和应用显着性的电催化反应的理解。 所研究的材料显示出有效的氧化和还原催化剂在小分子燃料电池应用中。因此，从这些基本研究中获得的信息可能有助于设计改进的燃料电池催化系统。