Microstructure control of WO3 film by adding nano-particles of SnO2 for NO2 detection in ppb level

To fabricate more excellent NO2 sensor with high sensor response and good linearity between the sensor response and NO2 concentration, the microstructure of WO3 lamellae was controlled by adding nano-particles of SnO2. It was found that the sintering of WO3 lamellae was inhibited by adding nano-particles of SnO2. The device using WO3 lamellae added a small amount of SnO2 nano-particles had the highest sensor response, exhibiting a high sensor response (S = 60-540) even to dilute NO2 (100–1000 ppb) in air at 200°C.