J Mater Sci Technol ›› 2008, Vol. 24 ›› Issue (04): 633-636.

• Research Articles • Previous Articles     Next Articles

Synthesis and Luminescent Properties of Planar-tip and Tapered-tip ZnO Nanorod Arrays

Chun-wen WANG, Jr-hau HE, Lih-juann CHEN   

  1. Department of Materials Science and Engineering, National Tsing-Hua University, Hsinchu City, 30013 Taiwan, China
  • Received:2008-03-09 Revised:1900-01-01 Online:2008-07-28 Published:2009-10-10
  • Contact: Lih-juann CHEN

Abstract: Vertically aligned ZnO nanorods were synthesized on a-plane sapphire via a metal catalyzed vapor phase transport and condensation process in a two-zone vacuum furnace. Planar-tip and tapered-tip ZnO nanorods were successfully synthesized by utilizing different source materials under the same growth conditions. The growth mechanisms were proposed to be vapor-liquid-solid (VLS) process for planar-tip ZnO nanorods and a combination of VLS and self-catalyzed processes for tapered-tip ZnO nanorods. From cathodoluminescence (CL) measurements, tapered-tip ZnO nanorods have more intense green emission than planar-tip ZnO nanorods, and therefore possess higher oxygen vacancy concentration than planar-tip ZnO nanorods. From CL characteristics, well-aligned planar-tip ZnO nanorods shall serve effectively as laser source, while well-aligned tapered-tip ZnO nanorods are suitable for direction-related optical applications.

Key words: ZnO, Well-aligned, Nanorods, Cathodoluminescence