Catalyst-free synthesis of zinc oxide (ZnO) nanostructures through the horizontal vapor phase crystal growth

Abstract

Zinc oxide nanomaterials were grown on quartz through noncatalytic horizontal vapor phase crystal growth from 600°C to 1200°C. The growth time was also varied between two to eight hours in two-hour increments while the ramp time was synchronized from 20 to 80 minutes. Scanning electron microscopy revealed that nanowires with lengths of a few microns and width of 40-130 nm were synthesized at lower temperatures and nanoblades of width 200 nm are formed at higher temperatures. Slow ramping rate was found to yield nanostructures that have smaller widths while less unreacted ZnO powder were observed at higher temperature and longer growth time.