title: Hydrothermal synthesis of various hierarchical ZnO nanostructures and their methane sensing properties.
abstract: Hierarchical flower-like ZnO nanorods, net-like ZnO nanofibers and ZnO nanobulks have been successfully synthesized via a surfactant assisted hydrothemal method. The synthesized products were characterized by X-ray powder diffraction and field emission scanning electron microscopy, respectively. A possible growth mechanism of the various hierarchical ZnO nanostructures is discussed in detail. Gas sensors based on the as-prepared ZnO nanostructures were fabricated by screen-printing on a flat ceramic substrate. Furthermore, their gas sensing characteristics towards methane were systematically investigated. Methane is an important characteristic hydrocarbon contaminant found dissolved in power transformer oil as a result of faults. We find that the hierarchical flower-like ZnO nanorods and net-like ZnO nanofibers samples show higher gas response and lower operating temperature with rapid response-recovery time compared to those of sensors based on ZnO nanobulks. These results present a feasible way of exploring high performance sensing materials for on-site detection of characteristic fault gases dissolved in transformer oil.
authors.affiliation: State Key Laboratory of Power Transmission Equipment & System Security and New Technology, Chongqing University, Chongqing 400030, China. zhouqu@cqu.edu.cn
authors.forename: Qu
authors.initials: Q
authors.lastname: Zhou
authors.forename: Weigen
authors.initials: W
authors.lastname: Chen
authors.forename: Lingna
authors.initials: L
authors.lastname: Xu
authors.forename: Shudi
authors.initials: S
authors.lastname: Peng