Large-scale synthesis of flowerlike ZnO nanostructure by a simple chemical solution route and its gas-sensing property

A large-scale flowerlike ZnO nanostructure is prepared using a very simple solution method at near room temperature. The flowerlike ZnO nanostructure is self-assembled by thin and uniform nanosheets with a thickness of approximately 18 nm. X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) are used to characterize the structure and morphology. The possible growth mechanism is carefully discussed based on the reaction process. The as-prepared ZnO nanoflowers exhibit a good response and reversibility to some organic gases, such as ethanol and n-butanol. The responses to 100 ppm ethanol and n-butanol are 25.4 and 24.1, respectively, at a working temperature of 320 °C. In addition, the sensors exhibit a good response to acetone, 2-propanol, and methanol. The relationship between the gas-sensing properties and the microstructure of the as-prepared ZnO nanoflowers is also investigated.