Suppression of UV Emission in ZnO Nanorods

Enhanced violet emission is obtained from ZnO NRs prepared by sol-gel method. Optical band-gap is tuned from 3.22 to 3.0 eV by annealing of the samples. Crystallite size is less than 48 nm for all samples. Rod-like structures with diameter between 50 and 200 nm are obtained in as-prepared samples. After annealing, UV emission is suppressed and the visible emission becomes stronger which may be useful for sources in the visible region.