Spectroelectrochemical Monitoring of Electrode Reactions by Multiple Specular Reflectance Spectroscopy.
Abstract
Multiple specular reflection is the basis of a new thin layer spectro-electrochemical cell which does not use optically transparent electrodes, the optical sensitivity of which exceeds that of cells using transparent electrodes by a factor of several hundred. As a result, the ability to detect short-lived intermediates and weakly absorbing species in spectroelectrochemical studies is much improved. Absorbance changes less than 5 x 10 to the minus 5 absorbance units per electrode reflection are readily observed. A cell 4cm long with a 120 micrometers spacing, operated to give approximately 330 reflections, was used to monitor optically the reduction of methylene blue and the reoxidation of the leuco form at concentrations as low as 5 x 10 to the minus 7M. For both reactions, the absorbance is linear with square root of t from 10 ms to ca 3 s, and the magnitude agrees well with values calculated from the geometry of the optical path. Among the advantages of the new technique are greatly increased optical sensitivity and the ability to use electrode materials which are not transparent. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1979
- Accession Number
- ADA076951
Entities
People
- Charles E. Baumgartner
- David A. Aikens
- Gary T. Marks
- Herbert H. Richtol
Organizations
- Rensselaer Polytechnic Institute