Title :
Surface Ionization Gas Detection on Platinum and Metal Oxide Surfaces
Author :
Hackner, A. ; Habauzit, A. ; Müller, G. ; Comini, E. ; Faglia, G. ; Sberveglieri, G.
Author_Institution :
EADS Innovation Works Germany, EADS Deutschland GmbH, Munich, Germany
Abstract :
Surface ionization (SI) gas detection experiments have been performed on platinum (Pt) and metal oxide (MOX) films. The probability of surface ion emission varies with temperature in an Arrhenius-type manner. Among all hydrocarbons studied so far those with amine functional groups exhibited the lowest activation energies allowing detection in the ppm concentration range at emitter operation temperatures of about 400degC. All other kinds of hydrocarbons could not be detected under these same conditions, not even if their concentrations were as high as 1% or 2%. Under high-temperature conditions (~800degC), this kind of selectivity breaks down and solid-state SI emitters start to behave in a similar way as flame ionization detectors, allowing detection of a much wider range of hydrocarbon species. Emitter materials with surface morphologies in the nanometer range were found to form much more efficient ion emitters than emitters with smooth surfaces.
Keywords :
chemical variables measurement; gas sensors; nanosensors; platinum; probability; surface ionisation; surface morphology; Arrhenius-type manner; amine functional groups; hydrocarbon species; metal oxide film; solid-state SI emitter; surface ion emission probability; surface ionization gas detection; surface morphology; Fires; Gas detectors; Hydrocarbons; Ion emission; Ionization; Platinum; Semiconductor films; Solid state circuits; Surface morphology; Temperature distribution; Charge transfer process; functional hydrocarbons; gas sensing mechanism; proton affinity; surface ionization (SI);
Journal_Title :
Sensors Journal, IEEE
DOI :
10.1109/JSEN.2009.2030705