ZnO nanowires by pulsed laser vaporization: synthesis and properties

We report a new pulsed-laser vaporization (PLV) technique to synthesize nanowires of single-crystal ZnO having a wurtzite structure by using colloidal gold nanoparticles as seeding catalysts. The average diameter of the nanowires is approximately 13 nm, with a very narrow range of 7 to 25 nm. The nanowires are straight for the most part, with the axes parallel to the [0001] growth direction. Raman and photoluminescence spectra from the nanowires and bulk ZnO are similar except for a approximately 510 nm band in the nanowires due to oxygen vacancies. The bulk-like vibrational and electronic properties of the nanowires is due to the diameter being larger than the threshold below which quantum confinement-induced effects are expected.