Room-temperature NH₃ gas sensor based on hydrothermally grown ZnO nanorods

A NH₃ gas sensor based on a ZnO nanorod array is fabricated by hydrothermal decomposition on a Au electrode. The as-grown ZnO nanorods have uniform diameter distribution and good crystal structure, shown by scanning electron microscopy, x-ray diffraction, high resolution transmission electron microscopy and photoluminescence emission characterizations. The gas sensing results show that the ZnO nanorod-based device responds well to ammonia gas at room temperature (sensitivity S is about 8).