Ce-doped ZnO nanorods based low operation temperature NO2 gas sensors

High performance gas sensors which can be operated at low temperature are needed for portable and low power consumption sensors. In this study, low operation temperature NO2 sensors can be achieved by growing the Ce-doped ZnO nanorods array films on the Al2O3 substrates with Pt spiral electrodes. Ce doping and high surface-to-volume ratio structure of ZnO nanorods not only improve the sensor response to NO2, but also reduce the operating temperature. Detection of 2 ppm NO2 in air at 100 °C can be achieved with fast response. We investigated the effects of electrode structure, surface texture and Ce content of sensing materials on the optical and gas sensing properties, together with the relationship between surface chemistry and gas sensing performance of Ce-doped ZnO nanorods.