Synthesis and size control of ZnO nanorods by conventional pulsed-laser deposition without catalyst

C-axis oriented ZnO nanorods were grown on both sapphire and silicon substrates by conventional pulsed-laser deposition (PLD) without catalyst. Investigations on the effects of PLD parameters reveal that the nanorods can be synthesized in a relatively wide range of substrate temperatures (550–700 °C) under high oxygen pressures (5–20 Torr). The size control was accomplished by adjusting substrate temperature and background pressure. The photoluminescence properties of the nanorods were closely related to the size difference, surface status and substrate nature.