Fiber Optical Micro-Detectors for Oxygen Sensing in Power Plants Progress Report (open access)

Fiber Optical Micro-Detectors for Oxygen Sensing in Power Plants Progress Report

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. Alkali salts of Mo{sub 6}Cl{sub 12} were synthesized and heated to 280 C for one hour in air. Optical measurements of the thermally treated material confirm the potential of the salts as lumophores in high temperature fiber optic sensors. In addition sol-gel films containing Mo{sub 6}Cl{sub 12} were dip coated on quartz substrates and heated at 200 C for one hour. Conditions were developed for successfully immobilizing monomeric complexes that are compatible with sol-gel processing.
Date: July 1, 2004
Creator: Baker, Gregory L.; Ghosh, Ruby N. & III, D.J. Osborn
System: The UNT Digital Library
Fiber Optical Micro-Detectors for Oxygen Sensing in Power Plants Progress Report (open access)

Fiber Optical Micro-Detectors for Oxygen Sensing in Power Plants Progress Report

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. High temperature measurements of the emission of clusters in sol gel films show that the luminescence intensity from the films follow a 1/T relationship from room temperature to 150 C, and then declines at a slower rate at higher temperatures. The large number of photons available at 230 C is consistent with simple low cost optics for fiber optic probes based on the emission from clusters in sol gel films.
Date: October 1, 2004
Creator: Baker, Gregory L.; Ghosh, Ruby N. & III, D.J. Osborn
System: The UNT Digital Library
Fiber Optical Micro-Detectors for Oxygen Sensing in Power Plants Progress Report (open access)

Fiber Optical Micro-Detectors for Oxygen Sensing in Power Plants Progress Report

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. The luminescence of Mo{sub 6}Cl{sub 12} immobilized in a sol-gel matrix was measured as a function of heater temperature up to 200 C, in an inert environment. While the luminescence decreased with temperature, the integrated intensity at 200 C should be sufficient to enable detection of the luminescence in a fiber geometry. Previously we found that aging Mo{sub 6}Cl{sub 12} at temperatures above 250 C converts the canary yellow Mo{sub 6}Cl{sub 12} to a non-luminescent gray solid. Optical and thermal aging experiments show that the alkali metal salts of Mo{sub 6}Cl{sub 12} have higher thermal stabilities and remain luminescent after aging at 280 C.
Date: April 1, 2004
Creator: Baker, Gregory L.; Ghosh, Ruby N. & III, D.J. Osborn
System: The UNT Digital Library