E8.4 - Detecting poisoning of metal oxide gas sensors at an early stage by temperature cycled operation
- AMA Conferences 2015
2015-05-19 - 2015-05-21
- Proceedings SENSOR 2015
- E8 - Gas Sensors IV
- M. Schüler, T. Fricke, T. Sauerwald, A. Schütze - Saarland University, Saarbrücken (Germany)
- 735 - 739
In this paper we study the effect of HMDSO (hexamethyldisiloxane) on an SnO2 metal oxide gas sensor in temperature cycled operation (TCO). Using TCO, the sensor discriminates between pure air, carbon monoxide and ethanol, both in the range of 1 ppm to 5 ppm. We could show that gas identification is still possible after poisoning with 340 ppm*min HMDSO, i.e. a HMDSO poisoning dose that fulfills the requirement of DIN EN 50194-1. Moreover, the poisoning dose can be quantified with a resolution of ±85 ppm*min again using data recorded in TCO mode, providing an easy method for early detection of HMDSO poisoning and a novel approach for sensor self-monitoring.