Abstract

Hexagonal zinc oxide (ZnO) nanotubes were synthesized from 0.05M zinc nitrate hexahydrate [Zn(NO<inf>3</inf>)<inf>2</inf>·6H<inf>2</inf>O] and hexamethylenetetramine (C<inf>6</inf>H<inf>12</inf>N<inf>4</inf>) by a sonochemical method under ambient conditions. White precipitates, obtained after ultrasonic irradiation for 60min, were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and photoluminescence spectroscopy (PL). The ZnO crystals had a tubular structure ̃500nm in length with a hexagonal cross section for both the inner and outer walls. The room temperature PL spectrum of ZnO nanotubes exhibited an ultraviolet (UV) emission peak, a sharp violet peak and a further broad visible band centered at 650 nm. © 2011 The Ceramic Society of Japan.