Gas sensors

Topic

Detector for halogenated organic compounds (Rice detector)

Electrochemical CO2/O2 sensor

Limiting-current type oxygen sensor for industrial applications

Oxygen sensor for inert gas systems and gas mixtures with combustible components

TCD array for selective gas analysis

Thick film sensor for H2 detection in chlorine

TCD array for selective gas analysis

Topic gas sensors

WLD-Array
© Fraunhofer IKTS
TCD module for sensor integration, Henze-Hauck GmbH.
Keramische-WLD-Sensorelemente
© Fraunhofer IKTS
TCD sensing elements in thick film technology.

Quantitative analysis of multi-component gas mixtures usually requires expensive analyzers based on mass spectrometry or gas chromatography or extensive implementation of complementary gas sensors. A different approach is based on the measurement of a gas mixture’s thermal conductivity at different temperatures, which allows to determine the gas composition quantitatively if the type of components is known. At Fraunhofer IKTS, a thermal conductivity detector (TCD) array for selective biogas analysis has been developed in cooperation with Henze-Hauck Prozessmesstechnik/Analytik GmbH.

 

Development results

 

The sensor array is suitable for quantitative analysis of a three components gas mixture consisting of CH4, CO2 und N2. Depending on the type of components, even four components can be identified quantitatively, e.g. CH4, CO2, N2 und H2. At the same time, the sensor array’s compact and modular design allows a cost-efficient and space-saving integration into existing process chains.

 

Services offered

 

  • Implementation of TCDs in thick film technology on ultrathin ceramic substrates (t≤60 µm)    
  • Adaption to further target gases depending on physical gas properties
  • Integration of catalytically active layers for the detection of specific gas components
  • TCD calibration and long term testing
  • Supply of sensor prototypes for evaluation purposes

References

S. Dietrich, M. Kusnezoff, S. Ziesche, J. Henze, Wärmeleitfähigkeitsdetektoren-Array zur selektiven Gasanalyse, Dresdner Sensor-Symposium, Konferenzband, 133-136, 2011, DOI: 10.5162/10dss2011/8.3