Materials development, fabrication and characterization for gas sensing applications
Topic gas sensors
When sensing gases, whether a pellistor, chemoresistive or electrochemical gas sensor is used, specific interactions between target gas and functional materials of the sensor (e.g. electrodes) are crucial for sensor signal formation. Furthermore, structural sensor components, which are supposed to be passive in terms of gas sensing, may also interact with gas species causing unwanted effects which have to be considered when choosing materials for sensor design and housing.
Besides the successful development of various types of gas sensors for O2, CO2, H2 and further gases, Fraunhofer IKTS has broad experience in the development of materials and functional layers for applications in printed electronics and sensors. The layers can be deposited on ceramic, metal and polymer substrates by various technologies.
Various test equipment is available for characterization of material and film properties and their interaction with gases in a wide range of temperatures and gas atmospheres. The characterization methods cover electrically or ionically conductive films or pellets, symmetrical/asymmetrical cells with sensing electrodes based on solid electrolytes or potentiometric sensor cells. Measurements comprise electrical pellet and film properties, cell voltages and currents as well as electrochemical impedance.
- Safety (explosion protection, work place safety)
- Industry (process and exhaust gas monitoring)
- Medicine and bio technology (respiratory analysis, incubators)
- Environmental monitoring (smart agriculture, livestock)
- Internet of things (smart home, etc.)
- Development of functional materials and formulation of thick film pastes and inks for gas sensing applications
- Development of functional films based on screen, inkjet and aerosol printing on a wide range of substrates (e.g. ceramic, polymers, metal)
- Heat treatment of functional films by batch processing in infrared or vacuum furnaces as well as innovative novel methods like laser sintering in milliseconds (High Density Power Laser, HDPL)
- Characterization of sensor materials and printed films
- Temperature range: room temperature to 1000 °C
- Gases: Ar, He, N2, O2, H2O, H2, CO, CO2, NOx, NH3, SOx, additional gases on request
- Measurement (dependent on sample type): Electrical resistance, voltage/current, impedance (EIS), oxygen partial pressure in gas stream before and after sample exposure
- Parallel determination of oxygen stoichiometry and electrical conductivity of complex oxides as a function of gas composition and temperature
- Development and adaption of electrochemical measurement techniques