Effect of different O2/N2 flow rate on the size and yield of ZnO nanostructures

Abstract

The effect of O₂/N₂ flow rate on the size and yield of ZnO nanostructures was studied in a horizontal tube furnace via a thermal evaporation process. When the total flow rate of N₂ and O₂ is 400 sccm, the height/diameter ratio of the ZnO nanonails decreases with the increasing of O₂ flow rate and the yield firstly increases then decreases. X-ray diffraction patterns indicate all ZnO nanonails grow preferentially along the [0001] direction. Room-temperature photoluminescence spectra show that the intensity ratio of UV to green emission increases with increasing O₂/N₂ flow rate. The CFD simulation results indicate that the controlled growth of ZnO nanonails can be achieved by adjusting the O₂/N₂ flow rate.