Mechanism of Oxygen Response in Carbon-Based Sensors

The mechanism of oxygen response in several newly synthesized oxygen-sensitive chars was studied with the use of EPR spectroscopy. The results suggest that the compounds contain two basic types of paramagnetic centers (PC). The change in oxygen concentration leads to a mutual and reversible transfor...

Full description

Saved in:
Bibliographic Details
Published in:Journal of magnetic resonance (1997) 2001-03, Vol.149 (1), p.85-89
Main Authors: Atsarkin, V.A., Demidov, V.V., Vasneva, G.A., Dzheparov, F.S., Ceroke, P.J., Odintsov, B.M., Clarkson, R.B.
Format: Article
Language:English
Subjects:
Carbon
Electrodes
Free Radicals - analysis
Humans
Magnetic Resonance Spectroscopy - instrumentation
Oximetry - instrumentation
Signal Processing, Computer-Assisted - instrumentation
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The mechanism of oxygen response in several newly synthesized oxygen-sensitive chars was studied with the use of EPR spectroscopy. The results suggest that the compounds contain two basic types of paramagnetic centers (PC). The change in oxygen concentration leads to a mutual and reversible transformation of PCs in chars, which is reflected in EPR parameters. The adsorbed molecular oxygen progressively disturbs the wave functions of the PCs and so breaks the Heisenberg exchange between them. At high oxygen concentration, the 2D dipole–dipole interaction between PCs at the surface comes into play and determines the EPR lineshape. A suggested model quantitatively describes the evolution of the basic EPR parameters of each PC as a function of oxygen concentration.
ISSN:1090-7807
1096-0856
DOI:10.1006/jmre.2000.2274