Controlled optical and magnetic properties of ZnO nanorods by Ar ion irradiation

Herein we report a controlled defect-related emission and magnetization properties of zinc oxide nanorods using low energy (2-5 keV) Ar ion irradiation. The ratio of the defect related emission to the excitonic emission decreases by an order magnitude due to the ion bombardment. The hysteresis loops of pristine and irradiated nanorods show ferromagnetic behavior at room temperature. A sharp decrease in the value of magnetization is due to an enhancement of irradiation time and energy. Combining with x-ray photoelectron spectroscopy results, a direct link between the magnetization and defect-emission of ZnO nanorods is established. (C) 2011 American Institute of Physics. [doi:10.1063/1.3574772]