Effect of Sulphur and Nitrogen Co-Doping On Energy Bandgap, Antioxidant and Antimicrobial Activity of Zinc Oxide Nanoparticles

Abstract

Semiconducting MO-NPs have been taken into consideration for their important applications like fast and profound detection, portability, high antimicrobial action, and relatively low cost compared to other conventional procedures. . Zinc oxide nanoparticles can safely be used as medicine, preservative in packaging, and photo catalysis and antimicrobial agents. It easily diffuses into the food material, kills the microbes, and prevents a human being from falling ill. The XRD result imiply some additional peak patterns with S-N-co-doped was observed which resulted from residual or incomplete converson of complexe compound S and N of synthesized nanoparticles even though a hexagonal structures of ZnO is not changed. In addition there was slightly change in diffraction angle both towards the lower and higher angle in 6%N-ZnO, as a result of ionic radius and bond length difference respectively as it was reported in other literatures. Crysal size of synthesized NPs has been calculated using FWHM , and the size of N-S-dual doped ZnO NPs has smallest compare to the single doped and pure ZnO NPs .The UV absorption spectra showed redshifts from 370 toward 377 nm and 378 nm due to the nitrogen and sulfur doping respectively while 370 towards 379 nm due to S-N-co doping. Accordingly, the approximated energy bandgap values for bare ZnO-NPs, 6%N-ZnO, 4%S-ZnO and S4-N6-ZnO were 2.97, 2.78, 2.69 and 2.63 eV respectively. From this, the S4-N6- ZnO NPs has minimum energy bandgap. The study results revealed that ZnO NPs functionality is modified by dual doping of S and nitrogen.doped and co-doped nanoparticles had good crystalline nature, and structures of hexagonal wurtzite. All undoped ZnO, 6%N doped, 4%S doped and S4-N6- co-doped ZnO nanoparticles demonstrated worthy antibacterial and antifungal activity against four bacterial strains and one fungal genus. Generally, S-N-co doped ZnO NPs were found to be possess more antimicrobial activities than undoped ZnO NPs.