NO-sensing characteristics of ZnO nanorods prepared by the ultrasound radiation method

In this study, zinc oxide (ZnO) sensors were fabricated from ZnO nanorods prepared by ultrasound radiation method, and their gas-sensing properties were investigated for nitric oxide (NO), trimethylamine ((CH3)(3)N), hydrogen sulphide (H2S), carbon monoxide (CO), and methyl mercaptan (CH3SH). In the procedure, zinc nitrate hydrate (Zn(NO3)(2)center dot 6H(2)O) and hexamethyleneteramine (C6H12N4,) were dissolved in deionized water and then the solution was irradiated with high-intensity ultrasound radiation for 1 h by employing a direct immersion of titanium horn. The length of the ZnO nanorods was from 250 nm to 500 nm and the diameter was from 40 nm to 80 nm. The size of the ZnO nanorods can be controlled by the concentration of the solution. The sensing characteristics of these nanostructures were investigated for three kinds of sensor fabricated by different concentrations (0.01, 0.005, and 0.001 M) of solution. It was observed that the property of the sensors was influenced by the morphology. The crystal structure and ceramic microstructure of the ZnO nanorods were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM).