Electrochemically modulated infrared spectroscopy

Kunimatsu, K. and Bewick, A. (1986) Electrochemically modulated infrared spectroscopy of adsorbed water in the inner part of the double layer part 1. Oxygen-hydrogen stretching spectra of water on gold in 1M perchloric acid. fnd. J. Technol., 24, 407-412. 

Electrochemically modulated infrared spectroscopy (EMIRS), involving potential modulation. Modulation frequencies from 1-100 Hz are employed and phase-sensitive detection used to calculate AR. 

One of the most commonly applied IR techniques developed to overcome these problems is the external reflectance technique. In this method, the shong solvent absorption is minimized by simply pressing a reflective working electrode against the IR transparent window of the electrochemical cell. The sensitivity problem, that is, the enhancement of the signal/noise ratio in the case of external reflectance techniques is solved by various approaches. These are, for instance, electrochemically modulated infrared spectroscopy (EMIRS), in situ FTIR (which use potential modulation), and polarization modulation infrared reflection absorption spectroscopy (PM-IRAS, FTIR) [86,117-123]. 

However, attempts to detect the hypothetical intermediate HSiFs species during porous Si formation by in situ Fourier-transform electrochemically modulated infrared spectroscopy have been unsuccessful [61]. Calculations show that if such a species or a similar one exists, their lifetime must be shorter than 0.3 ms. 

Electrochemically modulated infrared spectroscopy (EMIRS), polarization modulation infrared reflection-absorption spectroscopy (PM-IRRAS), and attenuated total reflectance (ATR) have also been used. (FTIR-ATR spectra are shown in Chap. 6, Fig. 6.11.)... 

Bewick A, Kunimatsu K, Pons BS, Russell JW (1984) Electrochemically modulated infrared spectroscopy (EMIRS) experimental details. J Electroanal Chem 160 47-61... 

Strategies for the development of novel catalytic materials and the design of highly active catalysts for DLFC applications largely depend on a detailed understanding of the reaction mechanism and, in particular, of the rate-limiting step(s) during the electrooxidation under continuous reaction conditions. The most commonly used technique in the electrochemical studies of fuel cell reaction mechanisms has been voltammetry, chronoamperometry (chronopotentiometry), in situ spectroscopic techniques, e.g., electrochemically modulated infrared spectroscopy (EMIRS) and infrared reflection-absorption spectroscopy (IRRAS), differential electrochemical mass spectroscopy (DEMS) and ex-situ techniques, e.g.. X-ray photoelectron spectroscopy (XPS) [92]. 

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