Investigation of magnesium addition in ZnO matrix using group II heptahydrate

Abstract

ZnO and MgZnO nanoparticles were prepared by the co-precipitation method utilizing zinc sulfate heptahydrate and magnesium sulfate heptahydrate; structural measurements were also carried out. An x-ray diffraction (XRD) study indicated that no peaks for other possible phases such as MgO or MgZn intermetallic compounds indicating pure wurtzite structure. All nanoparticles crystallized in a hexagonal wurtzite structure with different orientation diffraction peaks; the main peaks were (100), (002), and (101). Grain size (D) increased with increasing Mg concentrations. A scanning electron microscopy (SEM) analysis revealed that nanoparticle size increased by increasing the Mg concentration in a good qualitative with Scherrer equation and not only the size even the grain shape changed. In addition, optical measurements were taken infer that the band gap energy (Eg), extracted from Tauc’s plot, decreases with increasing of the Mg concentration doped, and found to be between 3.255 eV and 3.169 eV. The photoluminescence (PL) emission spectra show two peaks at the ultraviolet and green regions.

Zn1-xMgxO Nanocomposites: Synthesis, Structural, Optical Properties and Antibacterial Activity

“…The results demonstrate that the incorporation of Mg 2+ into the Zn 2+ site of the wurtzite lattice parameters which appeared in the band edge shift to lower wavelength (blue shift). This absorption edge was blue shifted with the increase of Mg concentrations from 400 to 330 nm at the sample Zn 0.2 Mg 0.8 O, the reason of increasing the absorption might be due to defect in the grain sizes and oxygen deficiency [31]. Also this is due to the increase in surface roughness which leads to more absorption at the surface and so to less transparency and less reflectivity [32].…”