表面增强红外光谱同时探测的酸平衡和电场
Murielle F Delley1,2, Eva M Nichols3,2, James M Mayer2
1Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056 Basel, Switzerland.
Journal of the American Chemical Society
|July 13, 2021
概括
了解电极表面的介面质子转移是电化学技术的关键. 这项研究表明,应用潜力在自组装单层中显著下降,影响表面酸度和电场.
科学领域:
- 电化学
- 表面科学
- 光谱学
背景情况:
- 在电化学技术中,介面质子转移至关重要.
- 了解应用电位和电解质条件对这些转移的影响至关重要.
- 自组装单层 (SAM) 广泛用于电极表面.
研究的目的:
- 研究应用电位和电解质条件如何影响电极表面的介面质子转移.
- 在黄金上检查4 - 墨乙烯酸 (4-MBA) 和4 - 墨乙烯 (4-MBN) 的混合SAM.
- 同时测量有效的酸度和界面电场.
主要方法:
- 在现场表面增强红外吸收光谱 (SEIRAS).
- 测量使用的电位,电解质pD和度各不相同.
- 分析4-MBN的 Stark 转移以确定当地的电场.
主要成果:
- SAM的有效酸度随着潜在的应用而变化,其中~90%的潜在下降在SAM层中.
- SAM的pKa显示了Nernstian对SAM边缘估计的体验潜力的依赖.
- 表面电荷密度受SAM头组,电解质组件,离子配对和离子透的影响.
结论:
- 应用潜力在SAM中显著下降,因此需要区分应用和经验潜力.
- 这项研究强调了功能化电极表面的经验潜力和特定离子效应的相关性.
- 这项研究首次对SAM电解质接口的有效酸度和电场进行了同时检查.
相关概念视频
Interfacial Electrochemical Methods: Overview
538
Interfacial electrochemical methods focus on the phenomena occurring at the boundary between an electrode and a solution, as opposed to bulk methods that concentrate on the solution's overall properties. These interfacial methods are classified as either static or dynamic based on the presence of a nonzero current in the electrochemical cell and the consistency of analyte concentrations. Static methods, such as potentiometry, measure the cell's potential without any significant current...
538
IR and UV–Vis Spectroscopy of Carboxylic Acids
4.9K
In IR spectroscopy of carboxylic acids, the C=O bond shows a characteristic band between 1710 and 1760 cm⁻¹, and the O–H bond exhibits a broad band between 2500 and 3300 cm⁻¹.
However, the stretching absorptions for the C=O bond vary depending on the structure of carboxylic acids. The C=O bond of the free carboxylic acids shows a higher stretching frequency, 1760 cm−1, while H-bonded carboxylic acids (dimers) exhibit stretching absorptions at a lower frequency,...
However, the stretching absorptions for the C=O bond vary depending on the structure of carboxylic acids. The C=O bond of the free carboxylic acids shows a higher stretching frequency, 1760 cm−1, while H-bonded carboxylic acids (dimers) exhibit stretching absorptions at a lower frequency,...
4.9K
Infrared (IR) Spectroscopy: Overview
3.4K
When electromagnetic radiation passes through a material, atoms or molecules transition from a lower to a higher energy state by absorbing radiation corresponding to the energy difference between the two states. The absorption of infrared (IR) radiation causes transitions between vibrational energy levels in a molecule. Therefore, IR spectroscopy is a useful analytical tool for determining the molecular structure of molecules.
Different compounds display unique properties due to their...
Different compounds display unique properties due to their...
3.4K


