Circumferentially grown ZnO nanowire forest on a suspended carbon nanowire for a highly sensitive gas sensor

We present a suspended ZnO nanowire forest as a highly sensitive gas sensor. ZnO nanowires were grown selectively on a suspended single glassy carbon nanowire using hydrothermal method so that the detrimental effects from the substrate inclusive of contamination, stagnant layer and limited mass transfer could be alleviated. The novel geometry of the radially grown ZnO nanowires resembling burs of a chestnut is expected to enhance the gas sensing capability because of enhanced mass transfer.