Ag2Te nanowires for humidity-resistant trace-level NO2 detection at room temperature

As one of the obstinate problems for gas sensors, humidity interference has troubled researchers for decades. In this short communication, an n-type semiconductor Ag2Te is selected as the NO2 gas sensing material. Through the hydrothermal method, Ag2Te nanowires are synthesized and then spin-coated on an integrated electrode to fabricate gas sensor. The sensing properties of the Ag2Te sensor are investigated at room temperature (~25 °C) and 50% relative humidity (RH), revealing its good sensing characteristics towards NO2 with a rapid response (10.2 s towards 5 ppm NO2), low limit of detection (ppb-level), and repeatable detection. It is worth noting that the Ag2Te sensor is humidity resistible. The resistance of Ag2Te sensor in air and 1 ppm NO2 are both stable in humidity range from 10% to 90% RH with resistance variation of 1.84%and 0.95% respectively, demonstrating the humidity-resistant property of the Ag2Te sensor. This work is expected to provide a new pathway for the development of room temperature humidity-resistant gas sensors.