ZnO nanorods were grown on Si substrate by hydrothermal method under various reaction time(12,24,and 36 h),Zn^2+concentrations(0.01,0.02,and 0.05 mol/L)and reaction temperatures(70-95~C).Their photoluminescence(PL)tests were taken at room temperature.Nanorods grown under longer reaction times or higher temperatures can emit stronger UV light and depressed green light,suggesting better crystallization of ZnO nanorods.Higher Zn^2+concentration results in stronger green band emitting,whereas the UV peak is depressed with the Zn^2+concentration over 0.02 mol/L.This indicates that excessive interstitial Zn defects may be introduced into the nanorods in Zn-rich environment.
