Large-scale fabrication of metallic Zn nanowires by thermal evaporation

Metallic Zinc (Zn) nanowires in large quantity are synthesized by thermal evaporation and vapor transport methods at low substrate temperature (100-200 degrees C) in the furnace tube placed in a conventional furnace in flowing Ar gas. A mixture of ZnO and graphite powder (ratio 2:1 by weight) is heated at nearly 1000 degrees C in the tube. Zn nanowires and other Zn nanostructures are formed at the end of the furnace tube at low temperatures. Upon annealing the as-made Zn nanowires at 500 degrees C for 1 h, oxidation occurred to form ZnO nanowires. Transmission electron microscopy images confirm that the annealed material is good-quality crystalline ZnO nanowires. Cathodoluminescence and photoluminescence spectra also show the band edge ultra violet peak emission at 381 nm and a broad band centered at 495 nm, which are the characteristics of ZnO material. (c) 2006 Published by Elsevier B.V.