Development of time-resolved and two-dimensional infrared spectroscopy for dynamic studies of solid/liquid interfaces

开发用于固/液界面动态研究的时间分辨和二维红外光谱

基本信息

批准号：
06554033
负责人：
OSAWA Masatoshi
金额：
$ 10.05万
依托单位：
Hokkaido University (1995)Tohoku University (1994)
依托单位国家：
日本
项目类别：
Grant-in-Aid for Developmental Scientific Research (B)
财政年份：
1994
资助国家：
日本
起止时间：
1994 至 1995
项目状态：
已结题

项目摘要

We have developed a novel infrared spectroscopy technique that enables real-time monitoring of reactions and dynamics at solid/liquid interfaces. This technique uses three advanced infrared technologies, surface-enhanced infrared absorption spectroscopy (SEIRAS), time-resolved FT-IR,and two-dimensional correlation analysis (2D-IR).SEIRAS probes the interface without the interference from the bulk solution at a very high sensitivity. Owing to the high sensitivity of SEIRAS,high-speed spectral measurements with rapid-scan and step-scan FT-IR inferferometry becomes possible. We have succeeded for the first time to monitor electrochemical reactions with time-resolutions ranging from microseconds to milliseconds. By the success of the time-resolved spectra measurements, the molecular information obtained from the spectra became to be directly correlated with the kinetic information obtained from conventional electrochemical measurements.The time-resolved spectra collected during reactions a … More re often complex due to the overlapping of absorption bands of reactants and products. To differentiate spectral features of the species by using their characteristic time-dependent behaviors, 2D correlation analysis technique was employed. The basic concept of 2D-IR is somewhat analogous to that of 2D correlation technique used in NMR.It was found that 2D-IR accentuates certain dynamic information that is not readily seen in the one-dimensional time-resolved spectra. One of the important characters of 2D-IR is that the time-sequence of the intensity changes of the bands arising from different species can be determined. This character is very useful in the studies of reaction processes.We have demonstrated the utilities of the developed technique through studies of several electrochemical reactions. One of the most significant achievements in this project is the success in the analysis of the "double-layr" structure. We found that water molecules reorient at the Au (111) electrode surface depending upon the surface charge. The results are in good agreement with recent molecular dynamics simulations of the double-layr. Less

我们开发了一种新型红外光谱技术，可以实时监测固/液界面的反应和动力学。该技术采用三种先进的红外技术：表面增强红外吸收光谱 (SEIRAS)、时间分辨傅里叶变换红外光谱 (FT-IR) 和表面增强红外吸收光谱 (SEIRAS)。二维相关分析（2D-IR）。SEIRAS 能够以非常高的灵敏度、高速地探测界面，不受本体溶液的干扰。通过快速扫描和步进扫描 FT-IR 干涉测量的光谱测量，我们首次成功地以微秒到毫秒的时间分辨率监测电化学反应。从光谱中获得的分子信息与从传统电化学测量中获得的动力学信息直接相关。由于吸收重叠，在反应过程中收集的时间分辨光谱通常很复杂为了利用其特征性的时间依赖性行为来区分反应物和产物的光谱特征，采用了 2D 相关分析技术。 2D-IR 的基本概念有点类似于 NMR 中使用的 2D 相关技术。研究发现，2D-IR 强调了在一维时间分辨光谱中不易看到的某些动态信息，2D-IR 的重要特征之一是强度变化的时间序列。可以确定不同物种产生的谱带，该特性在反应过程的研究中非常有用。我们通过对几个电化学反应的技术研究证明了该技术的实用性，该项目最重要的成就之一是在对“双层”结构的分析发现，水分子根据表面电荷在 Au (111) 电极表面重新定向，结果与最近的双层分子动力学模拟非常一致。