Ultrahigh Sensitive NO2 Gas Sensor Based on WO3 Nanorods

Metallic semiconductor oxides are widely used to detect various toxic and harmful gases including nitrogen dioxide (NO 2 ). In this work, tungsten oxide (WO 3 ) nanowires were synthesized by a facile solvothermal methods, the surface morphology showed nanorods character with length ranging from 300-500 nm and had a diameter with 50 nm after calcined in 600 °C. Moreover, the WO 3 nanorods exhibited a extremely high gas response of ~150 to 1 ppm NO 2 at a relative low temperature (160 °C). The high specific surface area and rich oxygen vacancy may contribute to this high response. The sensor based on WO 3 nanorods had a superior respond to very low concentration of NO 2 revealed a promising candidate for the manufacture of cost effective gas sensors.