A comparative study of the gas sensing properties of hierarchical ZnO nanostructures

Two types of ZnO nanostructure have been fabricated to make a comparative study on their gas sensing performance: the conventional ZnO nanowire arrays were synthesized by hydrothermal method and the hierarchical ZnO nanowires/nanofibers nanostructures were prepared through a combination of the hydrothermal and electrospinning methods. Field emission scanning electron microscopy study showed a quiet homogeneous morphology both for both nanostructures. Three kinds of commonly used gases, such as ethanol, acetone and ammonia were chosen for ZnO nanostructure gas sensing property study. The UV-Visible spectroscopy measurements showed a higher detection sensitivity of ZnO NWs for ammonia compared to ethanol and acetone, and an enhanced sensing performance for the hierarchical nano- structure, which has a higher surface to volume ratio. On the other hand, the enhancement was more obviously in the case of ethanol sensing. (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)