Gas sensors

Topic

Limiting-current type oxygen sensor for industrial applications

Electrochemical CO2/O2 sensor

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

Detector for halogenated organic compounds (Rice detector)

Limiting-current type oxygen sensor for industrial applications

Topic gas sensors

© Fraunhofer IKTS
Miniaturized limiting-current type oxygen sensor.
© Fraunhofer IKTS
Measurement characteristic, comparison with theoretical values.

Determining the oxygen content in gas mixtures is important for several applications like combustion engines, medical systems for respiratory gas monitoring and various industrial processes. By appropriately choosing measurement principle, sensor design and operating parameters, oxygen sensors can be adapted to various applications. Fraunhofer IKTS has recently developed a limiting-current type oxygen sensor based on a ceramic solid electrolyte, which features a self-diagnosis functionality.

Amperometric oxygen measurement offers some distinct advantages over other measuring principles. First of all, operation of limiting-current type oxygen sensors does not require a reference gas. The theoretical limiting current can easily be calculated, allowing a facile sensor calibration and self-diagnosis using ambient air. In contrast to the logarithmic signal dependence of potentiometric oxygen sensors, the linear response of limiting-current type sensors permits the use of a larger measuring range.

 

Development results

 

A limiting-current type oxygen sensor has been successfully miniaturized by IKTS to a size of 3.5 x 4.0 x 0.5 mm³ and its performance proven for oxygen measurement in respiratory analysis. The sensor components are manufactured by thick film technology (screen printing) and assembled using a high-temperature glass solder. The sensor features excellent response behaviour in the concentration range 10-25 vol% O2, which is relevant for respiratory analysis.

 

Services offered

 

  • Customization of sensor geometry, measuring range and operating parameters
  • Sensor characterization and simulation to derive calibration data
  • Sensor packaging and integration via ceramic joining technology
  • Supply of sensor prototypes
  • Development and transfer of sensor manufacturing technologies for industrialization