Field emission property of ZnO nanoneedle arrays with differentmorphology

ZnO nanoneedle arrays were prepared using a chemical solution route on fluorine-doped SnO2 conductive glass at low temperature. Crystal structure and morphology of the samples were characterized by X-ray diffraction, scanning electron microscope and high-resolution transmission electron microscope. All the results indicate that high quality ZnO nanoneedles array were grown vertically on the substrates along the (0001) direction. The morphology of the ZnO nanoneedles was controlled by 1-3-diaminopropane concentration. As the concentration of 1-3-diaminopropane increases, transformation from ZnO nanorod to ZnO nanoneedle was realized. Correspondingly, an enhanced field emission property was observed in the ZnO nanoneedle array with sharpertip.

► Vertical ZnO nanoneedle arrays were grown on FTO by a hydrothermal method.
► Transformation from ZnO nanorod to ZnO nanoneedle was realized by controlling 1-3-diaminopropane concentration in the growth solution.
► Enhanced field emission property was observed in the ZnO nanoneedles with sharpertip.