Gas Sensor Properties of ZnO Nanorods Grown by Chemical Bath Deposition

This work shows a study about the growth of ZnO nanorods by chemical bath deposition and their application as gas sensors. ZnO nanorods were prepared and Au-decorated ZnO nanorods and the samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and gas sensing response measurements. XRD analysis shows the presence of the ZnO phase. SEM results show that it is possible to observe the formation of uniform dense well-aligned ZnO nanorods. The results also show that the ZnO nanorod surfaces have been successfully decorated with Ag nanoparticles. Au nanoparticles with few nanometers of diameter were distributed over the ZnO nanorods surface. By the gas sensing response measurements it was possible to verify that the samples behaved as an n-type semiconductor. Furthermore, the Au-decorated ZnO nanorods gas sensors show an enhanced response at 300 degrees C.