A miniature inexpensive, oxygen sensing element

Technical Report · Mon Oct 07 00:00:00 EDT 1991

DOI:https://doi.org/10.2172/5068581· OSTI ID:5068581

Arenz, R W

An exhaustive study was conducted to determine the feasibility of Nernst-type oxygen sensors based on ceramics containing Bi{sub 2}O{sub 3}. The basic sensor design consisted of a ceramic sensing module sealed into a metal tube. The module accommodated an internal heater and thermocouple. Thermal-expansion-matched metals, adhesives, and seals were researched and developed, consistent with sequential firings during sensor assembly. Significant effort was devoted to heater design/testing and to materials' compatibility with Pt electrodes. A systematic approach was taken to develop all sensor components which led to several design modifications. Prototype sensors were constructed and exhaustively tested. It is concluded that development of Nerst-type oxygen sensors based on Bi{sub 2}O{sub 3} will require much further effort and application of specialized technologies. However, during the course of this 3-year program much progress was reported in the literature on amperometric-type oxygen sensors, and a minor effort was devoted here to this type of sensor based on Bi{sub 2}O{sub 3}. These studies were made on Bi{sub 2}O{sub 3}-based ceramic samples in a multilayer-capacitor-type geometry and amperometric-type oxygen sensing was demonstrated at very low temperatures ({approximately} 160{degree}C). A central advantage here is that these types of sensors can be mass-produced very inexpensively ({approximately} 20--50 cents per unit). Research is needed, however, to develop an optimum diffusion-limiting barrier coating. In summary, the original goals of this program were not achieved due to unforeseen problems with Bi{sub 2}O{sub 3}-based Nernst sensors. However, a miniature amperometric sensor base on Bi{sub 2}O{sub 3} was demonstrated in this program, and it is now seen that this latter sensor is far superior to the originally proposed Nernst sensor. 6 refs., 24 figs.

• Research Organization: CeramPhysics, Inc., Westerville, OH (United States)
• Sponsoring Organization: USDOE; USDOE, Washington, DC (United States)
• DOE Contract Number: FG01-88CE15401
• OSTI ID: 5068581
• Report Number(s): DOE/CE/15401-T13; ON: DE92001884
• Country of Publication: United States
• Language: English

Related Subjects

47 OTHER INSTRUMENTATION
37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
36 MATERIALS SCIENCE
AMPEROMETRY
USES
MEASURING INSTRUMENTS
FEASIBILITY STUDIES
NERNST EFFECT
OXYGEN
DETECTION
BISMUTH OXIDES
CERAMICS
FABRICATION
GLASS
HEATERS
MATERIALS
PROGRESS REPORT
SEALS
BISMUTH COMPOUNDS
CHALCOGENIDES
DOCUMENT TYPES
ELEMENTS
NONMETALS
OXIDES
OXYGEN COMPOUNDS
TITRATION
440800* - Miscellaneous Instrumentation- (1990-)
400102 - Chemical & Spectral Procedures
360603 - Materials- Properties