Synthesis of Zinc Oxide nanoparticles using Chrysopogonzizanioidesgrass extract, its applications in Photodegradation and Antimicrobial Activity

Abstract

\n Zinc oxide nanoparticles (ZnONPs) were synthesized using Zinc nitrate hexahydrate as an oxidizer and Chrysopogonzizanioides (Vetiver) grass as a novel fuel. The X Ray Diffraction pattern as well as the Rietveld refinement showed a single-phase wurtzite structure. The average crystallite size and the lattice strain were estimated using Williamson-Hall plot. A very small value of lattice strain indicates that there is no strain and the crystal lattice is very stable. Thepresence of various functional groups in the plant extract and the Zinc –Oxygen bonding in the ZnONPs were confirmed by FTIR. The surface morphology was investigated using SEM and it showed nanorod like structure. The elemental mapping was carried out using EDAX. The EDAX spectrum suggests formation of ZnO nanorods along with high proportion of carbon and low proportion of Si as well as K might have resulted from the rich organic profile of Chrysopogon zizanioidesgrass extract. Within the UV- Visible Spectrum at 300 nm, the highly blue shifted strong absorption band was observed due to the strong quantum confinement effect. The band gap was observed to be 3.628 eV. The photodegradation of RB2 dye was studied over ZnONPs catalyst and it showed excellent photocatalytic activity. The catalyst was active up to five cycles without losing much of its efficiency. Further antimicrobial activity was tested against broad range of micro-organisms namely Staphylococcus aureus, Escherichia coli and much prevalent human fungal pathogen Candida albicans. The Minimum inhibitory concentration (MIC) for each micro-organism was determined using broth micro dilution assay.