title: Two-step growth of hexagonal-shaped ZnO nanowires and nanorods and their properties.
abstract: Single-crystalline with perfect hexagonal-shaped ZnO nanowires and nanorods, possessing the Zn-terminated (0001) facets bounded with the six-crystallographic equivalent [0110] surfaces, have been grown on Au-coated silicon substrate via thermal evaporation method using the metallic zinc powder in presence of oxygen. The detailed structural analyses reveal that the obtained nanostructures are single-crystalline with the wurtzite hexagonal phase and are preferentially oriented in the c-axis, [0001] direction. Raman spectra exhibit a sharp and strong optical phonon E2 mode at 437 cm(-1) further confirms the good crystal quality with wurtzite hexagonal crystal structure for the deposited products. The room-temperature photoluminescence (PL) spectra, for both the structures, showed a sharp and strong UV emission with a suppressed green emission, indicating the good optical properties for the as-grown nanostructures.
authors.affiliation: School of Chemical Engineering and Technology, Chonbuk National University, Chonju 561-756, South Korea.
authors.forename: Ahmad
authors.initials: A
authors.lastname: Umar
authors.forename: S H
authors.initials: SH
authors.lastname: Kim
authors.forename: J H
authors.initials: JH
authors.lastname: Kim
authors.forename: Y B
authors.initials: YB
authors.lastname: Hahn