Simultaneous detection of atmosphere induced mass and conductivity variations using high temperature resonant sensors

A sensor concept is presented which enables detection of conductivity and mass related changes induced in gas sensitive films deposited onto the surface of high temperature crystal microbalances with special electrode design. This unique superposition of effects on resonant frequency increases the selectivity of high temperature resonant gas sensors while retaining the simplicity of a single data acquisition technique, i.e. resonant frequency measurement. Environmental induced conductivity changes of sensor films alter the effective resonator electrode size and therefore the average mass sensitivity. Using this concept, the ability of such a sensor to distinguish between H-2 and CO is demonstrated. (c) 2005 Elsevier B.V. All rights reserved.