Sonochemical Method for Fabricating a High-performance ZnO Nanorod Sensor for CO Gas Detection

ZnO nanorod-based gas sensors were fabricated via a sonochemical route, and their gas sensing characteristics, especially for CO gas, were examined by varying the diameter of the nanorods. The advantages of the proposed method are a high speed of processing and a low detection limit for CO gas. The sensors based on aligned ZnO nanorods on a substrate were highly sensitive to CO gas with a low detection limit of 1 ppm at 350 degrees C. A complete regeneration was also observed. A mechanism for sensing CO gas on the surface of a ZnO nanorod is proposed.