Open AccessFIBER OPTICAL MICRO-DETECTORS FOR OXYGEN SENSING IN POWER PLANTS
Author(s) -
Gregory L. Baker,
Ruby N. Ghosh,
III Osborn,
Po Zhang
Publication year - 2005
Language(s) - English
Resource type - Reports
DOI - 10.2172/838219
Subject(s) - molybdenum , luminescence , quenching (fluorescence) , materials science , oxygen sensor , oxygen , optical fiber , chloride , sol gel , oxygen permeability , analytical chemistry (journal) , fiber , chemistry , optoelectronics , nanotechnology , optics , composite material , metallurgy , chromatography , physics , organic chemistry , fluorescence
A reflection mode fiber optic oxygen sensor that can operate at high temperatures for power plant applications is being developed. The sensor is based on the {sup 3}O{sub 2} quenching of the red emission from hexanuclear molybdenum chloride clusters. One of the critical materials issues is to demonstrate that the luminescent cluster immobilized in the sol-gel porous support can withstand high temperature. At the same time the sol-gel matrix must have a high permeability to oxygen. Using a potassium salt of the molybdenum clusters, K{sub 2}Mo{sub 6}Cl{sub 14}, we have established the conditions necessary for deposition of optical quality sol-gel films. From spectroscopic measurements of the film we have shown that the cluster luminescence is stable following heat cycling of 1 hour at 250 C. Quenching of a factor of 4X between pure nitrogen and 21% oxygen was observed for films cured directly at 200 C. These are promising results for a high temperature fiber optical oxygen sensor based on molybdenum chloride clusters