Characterization of Zinc oxide Nanostructures prepared by hydrothermal method with Antibacterial property

Ibrahim Abdulkareem Ali

doi:10.30723/ijp.v17i42.448

Abstract

In this study, Zinc oxide nanostructures were synthesized via a hydrothermal method by using zinc nitrate hexahydrate and sodium hydroxide as a precursor. Three different annealing temperatures were used to study their effect on ZnO NSs properties. The synthesized nanostructure was characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), Atomic force microscope (AFM), and Fourier Transform Infrared Spectroscopy (FTIR). Their optical properties were studied by using UV -visible spectroscopy. The XRD analysis confirms that all ZnO nanostructures have the hexagonal wurtzite structure with average crystallite size within the range of (30.59 - 34.52) nm. The crystallite size increased due to the incensement of annealing temperature. FESEM analysis indicates that ZnO has hexagonal shape of cylindrical pores, plate-like nanocrystals and Nanorods. AFM analysis shows that the average surface roughness of ZnO Nanostructures increases from 3.96 to 19.1 nm with the increase of annealing temperature. The FTIR peaks indicate successful preparation of ZnO Nanostructures. The FTIR method was used to analyses the chemical bonds which conformed the present of the Zn-O group in the region between (400-500) cm-1. The UV-visible showed a red shift in the absorption spectra related to the shift in the energy gap related to increase in the particle size. the band gap energy has been calculated from the optical absorption spectra. The annealing process has been fond more effective on the value of energy gap. As the annealing temperature increases, the value of energy gap, increases as well; from (3.12to 3.22) eV. The prepared Nanostructure is used for antibacterial property. It shows strong antibacterial activity against S. aureus and P.aeuruginosa bacteria by the agar disc diffusion method. The white precipitate of ZnO NSs has superior antibacterial activity on gram-positive (S. aureus) than the gram-negative (P.aeuruginosa) bacteria.

Highlights

Zinc oxide nanostructures took awareness in modern materials science due to its properties [1]
Zinc oxide nanoparticles exist in white powder form and exhibit an electric property of n-type conductive while its p-type conductivity may obtained by special synthesis process
Our study showed higher antibacterial activities to gram bacteria positive (S. aureus) than the gram-negative bacteria (P.aeuruginosa) and the analysis obtained inhibition efficacy of ZnO nanostructures strongly dependent on concentration and size

Summary

Introduction

Zinc oxide nanostructures took awareness in modern materials science due to its properties [1]. It’s the first time we synthesis ZnO NSs utilized the molarity 2.5 M NaOH concentrations and 0.2M Zinc nitrate hexahydrate by hydrothermal method. Our study showed higher antibacterial activities to gram bacteria positive (S. aureus) than the gram-negative bacteria (P.aeuruginosa) and the analysis obtained inhibition efficacy of ZnO nanostructures strongly dependent on concentration and size. ZnO nanostructure was prepared via hydrothermal growth by utilized zinc nitrate hexahydrate, sodium hydroxide as precursors. In this work Atomic Force Microscope (CSPM-AA3000), AFM was utilized as an instrument to measure the granularity accumulation distribution, roughness, and grain size of the ZnO nanoparticles. In this test three dimensional images of the surface of the ZnO nanostructure are obtained. The inhibition zone could form around disc and measured in “millimeters” (mm) and recorded

Results and discussions

Conclusions