Improved response and sensitivity with low power consumption gas sensors based on Pt/semiconducting oxide/Pt configuration

For instance the response of TBE-TiO2:Cr sensors towards 50 ppm NO2 at 200 °C was 212 with fast response/recovery time [1]. This was ten times higher than the sensitivity measured with interdigitated sensor configuration. Through the impedance equivalent circuit modelling, the contribution of sensor components and interfaces on sensing has been identified. It is found from the gas sensing tests of TBE based sensors with covered surface that the gas reaction beneath Pt-TE is dominating. This work aims at low temperature operation of H2 and NO2 sensors based on undoped and doped TiO2 layers with top-bottom electrode (TBE) configuration. For comparison purposes, the same sensing layers were also coated on classical interdigitated electrodes (IDEs).