Controlled growth of flower-like, rod-like, and snowflake-like ZnO nanostructures using agarose as biotemplate and its photoluminescence property

Different nanostructures such as flower-like, rod-like, and snowflake-like of ZnO have been synthesized by varying the amount of agarose using sonochemical method. It is found that morphology is governed by amount of agarose as well as ultrasonic treatment. Three amounts of agarose 0.01, 0.1, and 1.00 g are used to investigate its effect on ZnO. X-ray diffraction (XRD) confirmed the formation of single phase with hexagonal structure. Scanning electron microscopy (SEM) showed flower-like, rod-like, and snowflake-like morphology for 1.00, 0.1, and 0.01 g agarose, respectively. UV/Visible absorption study showed blue shift at band-edge absorption in comparison to bulk ZnO. Photoluminescence spectra showed band-edge emission at 399 nm for lowest amount of agarose which quenched on increasing the agarose amount. These findings show a better and more environment friendly procedure for production of ZnO of readily adjustable morphology.