Nanocomposite thin films for high temperature optical gas sensing of hydrogen
First Claim
1. A method of monitoring hydrogen in a high temperature gas stream comprising:
- generating the high temperature gas stream, where the high temperature gas stream has a temperature greater than about 500°
C.;
placing a hydrogen sensing material in the high temperature gas stream, where the hydrogen sensing material is comprised of,an inert matrix, where the inert matrix is stable at the gas stream temperature, and where the inert matrix is optically transparent over a light wavelength range, and where the inert matrix has a bandgap greater than or equal to 5 eV and has an oxygen ion conductivity of less than 10−
7 S/cm at a temperature of 700°
C.,a plurality of gold nanoparticles dispersed in the inert matrix, where an individual gold nanoparticle in the plurality of gold nanoparticles is comprised of elemental gold, and where the plurality of gold nanoparticles have an average nanoparticle diameter of less than about 100 nanometers;
contacting the hydrogen sensing material with a monitored stream, where the monitored stream is at least a portion of the high temperature gas stream, and where the monitored stream has a temperature greater than about 500°
C., and illuminating the hydrogen sensing material with a light source emitting incident light;
collecting exiting light, where the exiting light is light that originates at the light source and is transmitted or reflected by the hydrogen sensing material, and monitoring a plasmon resonance peak position based on a comparison of the incident light and the exiting light using absorption spectroscopy; and
detecting hydrogen based on a peak shift of the plasmon resonance peak position, thereby monitoring hydrogen in the high temperature gas stream.
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Accused Products
Abstract
The disclosure relates to a plasmon resonance-based method for H2 sensing in a gas stream at temperatures greater than about 500° C. utilizing a hydrogen sensing material. The hydrogen sensing material is comprised of gold nanoparticles having an average nanoparticle diameter of less than about 100 nanometers dispersed in an inert matrix having a bandgap greater than or equal to 5 eV, and an oxygen ion conductivity less than approximately 10−7 S/cm at a temperature of 700° C. Exemplary inert matrix materials include SiO2, Al2O3, and Si3N4 as well as modifications to modify the effective refractive indices through combinations and/or doping of such materials. At high temperatures, blue shift of the plasmon resonance optical absorption peak indicates the presence of H2. The method disclosed offers significant advantage over active and reducible matrix materials typically utilized, such as yttria-stabilized zirconia (YSZ) or TiO2.
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Citations
20 Claims
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1. A method of monitoring hydrogen in a high temperature gas stream comprising:
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generating the high temperature gas stream, where the high temperature gas stream has a temperature greater than about 500°
C.;placing a hydrogen sensing material in the high temperature gas stream, where the hydrogen sensing material is comprised of, an inert matrix, where the inert matrix is stable at the gas stream temperature, and where the inert matrix is optically transparent over a light wavelength range, and where the inert matrix has a bandgap greater than or equal to 5 eV and has an oxygen ion conductivity of less than 10−
7 S/cm at a temperature of 700°
C.,a plurality of gold nanoparticles dispersed in the inert matrix, where an individual gold nanoparticle in the plurality of gold nanoparticles is comprised of elemental gold, and where the plurality of gold nanoparticles have an average nanoparticle diameter of less than about 100 nanometers; contacting the hydrogen sensing material with a monitored stream, where the monitored stream is at least a portion of the high temperature gas stream, and where the monitored stream has a temperature greater than about 500°
C., and illuminating the hydrogen sensing material with a light source emitting incident light;collecting exiting light, where the exiting light is light that originates at the light source and is transmitted or reflected by the hydrogen sensing material, and monitoring a plasmon resonance peak position based on a comparison of the incident light and the exiting light using absorption spectroscopy; and detecting hydrogen based on a peak shift of the plasmon resonance peak position, thereby monitoring hydrogen in the high temperature gas stream. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
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12. A method of monitoring hydrogen in a high temperature gas stream comprising:
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generating the high temperature gas stream, where the high temperature gas stream has a temperature greater than about 500°
C. and less than about 1000°
C.;placing a hydrogen sensing material in the high temperature gas stream, where the hydrogen sensing material is comprised of, an inert matrix, where the inert matrix is stable at the gas stream temperature, and where the inert matrix is optically transparent over a light wavelength range, and where the inert matrix has a bandgap greater than or equal to 5 eV and has an oxygen ion conductivity less than approximately 10−
7 S/cm at a temperature of 700°
C.,a plurality of gold nanoparticles dispersed in the inert matrix, where an individual gold nanoparticle in the plurality of gold nanoparticles is comprised of elemental gold, and where the plurality of gold nanoparticles have an average nanoparticle diameter of less than about 50 nanometers, and where the plurality of gold nanoparticles is comprised of individual gold nanoparticles separated by an average nanoparticle spacing, where the average nanoparticle spacing is greater than about 5 times the average nanoparticle diameter; contacting the hydrogen sensing material with a monitored stream, where the monitored stream is at least a portion of the high temperature gas stream, and where the monitored stream has a temperature greater than about 500°
C. and less than about 1000°
C., and illuminating the hydrogen sensing material with a light source emitting incident light;collecting exiting light, where the exiting light is light that originates at the light source and is transmitted or reflected by the hydrogen sensing material, and monitoring a plasmon resonance peak position based on a comparison of the incident light and the exiting light using absorption spectroscopy; and detecting hydrogen based on a peak shift of the plasmon resonance peak position, thereby monitoring hydrogen in the high temperature gas stream. - View Dependent Claims (13, 14, 15, 16, 17, 18)
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19. A method of monitoring hydrogen in a high temperature gas stream comprising:
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generating the high temperature gas stream, where the high temperature gas stream has a temperature greater than about 500°
C. and less than about 1000°
C.;placing a hydrogen sensing material in the high temperature gas stream, where the hydrogen sensing material is comprised of, an inert matrix, where the inert matrix is stable at the gas stream temperature, and where the inert matrix is optically transparent over a light wavelength range, and where the inert matrix has a bandgap greater than or equal to 5 eV and has an oxygen ion conductivity less than 10−
7 S/cm at a temperature of 700°
C.,a plurality of gold nanoparticles dispersed in the inert matrix, where an individual gold nanoparticle in the plurality of gold nanoparticles is comprised of elemental gold, and where the plurality of gold nanoparticles have an average nanoparticle diameter of less than about 50 nanometers, and where the plurality of gold nanoparticles is comprised of individual gold nanoparticles separated by an average nanoparticle spacing, where the average nanoparticle spacing is greater than about 5 times the average nanoparticle diameter; ascertaining a matrix refractive index, where the matrix refractive index is the refractive index of the inert matrix; providing a fiber optic cable having a first end and a second end, where the fiber optic cable is comprised of a core material, where the core material has a refractive index greater than the matrix refractive index, and placing the hydrogen sensing material in contact with the core material at a location between the first end of the fiber optic cable and the second end of the fiber optic cable; contacting the hydrogen sensing material with a monitored stream, where the monitored stream is at least a portion of the high temperature gas stream, and where the monitored stream has a temperature greater than about 500°
C. and less than about 1000°
C.,emitting incident light from a light source into the core material at the first end of the fiber optic cable and generating an evanescent wave in the hydrogen sensing material; gathering exiting light from the core material at the second end of the fiber optic cable, and monitoring a plasmon resonance peak position based on a comparison of the incident light and the exiting light using absorption spectroscopy; and detecting hydrogen based on a peak shift of the plasmon resonance peak position, thereby monitoring hydrogen in the high temperature gas stream. - View Dependent Claims (20)
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Specification