Flowerlike ZnO nanocones and nanowires: Preparation, structure, and luminescence

Flowerlike ZnO nanocone and nanowire arrays have been grown on a Zn foil via a solution-phase approach at low temperature. The tips of the nanocones are about 70–160nm in diameter and their roots are as thick as 350nm; the diameters of the nanowires are around 70–110nm. Both the nanocones and nanowires grow preferentially along the [0001] direction. Transmission electron microscopy analysis reveals that the surface of the ZnO nanocones is corrugated or protuberant while the nanowires have a smooth surface. Both shapes demonstrate a strong UV luminescence band around 385nm, and the nanocones also show three weak bands at 421, 484.6, and 532nm in the blue-green range.