Nanocrystalline films for gas-reactive applications
Abstract
A gas sensor for detection of oxidizing and reducing gases, including O.sub.2, CO.sub.2, CO, and H.sub.2, monitors the partial pressure of a gas to be detected by measuring the temperature rise of an oxide-thin-film-coated metallic line in response to an applied electrical current. For a fixed input power, the temperature rise of the metallic line is inversely proportional to the thermal conductivity of the oxide coating. The oxide coating contains multi-valent cation species that change their valence, and hence the oxygen stoichiometry of the coating, in response to changes in the partial pressure of the detected gas. Since the thermal conductivity of the coating is dependent on its oxygen stoichiometry, the temperature rise of the metallic line depends on the partial pressure of the detected gas. Nanocrystalline (<100 nm grain size) oxide coatings yield faster sensor response times than conventional larger-grained coatings due to faster oxygen diffusion along grain boundaries rather than through grain interiors.
- Inventors:
- Issue Date:
- Research Org.:
- Univ. of Chicago, IL (United States)
- Sponsoring Org.:
- USDOE
- OSTI Identifier:
- 1174727
- Patent Number(s):
- 6,691,554
- Application Number:
- 09/833,168
- Assignee:
- University Of Chicago OSTI
- DOE Contract Number:
- W-31-109-ENG-38
- Resource Type:
- Patent
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 36 MATERIALS SCIENCE
Citation Formats
Eastman, Jeffrey A., and Thompson, Loren J. Nanocrystalline films for gas-reactive applications. United States: N. p., 2004.
Web.
Eastman, Jeffrey A., & Thompson, Loren J. Nanocrystalline films for gas-reactive applications. United States.
Eastman, Jeffrey A., and Thompson, Loren J. Tue .
"Nanocrystalline films for gas-reactive applications". United States. https://www.osti.gov/servlets/purl/1174727.
@article{osti_1174727,
title = {Nanocrystalline films for gas-reactive applications},
author = {Eastman, Jeffrey A. and Thompson, Loren J.},
abstractNote = {A gas sensor for detection of oxidizing and reducing gases, including O.sub.2, CO.sub.2, CO, and H.sub.2, monitors the partial pressure of a gas to be detected by measuring the temperature rise of an oxide-thin-film-coated metallic line in response to an applied electrical current. For a fixed input power, the temperature rise of the metallic line is inversely proportional to the thermal conductivity of the oxide coating. The oxide coating contains multi-valent cation species that change their valence, and hence the oxygen stoichiometry of the coating, in response to changes in the partial pressure of the detected gas. Since the thermal conductivity of the coating is dependent on its oxygen stoichiometry, the temperature rise of the metallic line depends on the partial pressure of the detected gas. Nanocrystalline (<100 nm grain size) oxide coatings yield faster sensor response times than conventional larger-grained coatings due to faster oxygen diffusion along grain boundaries rather than through grain interiors.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {2004},
month = {2}
}