Simple Fabrication Method for ZnO Nanoneedle Structures

In this work, we demonstrated a simple synthesis method for ZnO nanoneedle structures which were fabricated at atmospheric pressure. Nanoneedles with diameter in the range 20-40 nm were synthesized in a tube-furnace maintained at 800 °C by evaporation of Zn nanoparticles in humidified Ar flow at 0.25 lpm. The nanostructures were grown on Si substrates at 725-750 °C without any catalyst. The fabricated needle structures show strong UV photoluminescence and weak yellow/orange emission, which indicates the excellent crystal quality of the nanostructures. X-ray diffraction (XRD) found only peaks corresponding to hexagonal ZnO. No peaks from Zn or other impurities were found