Effect of ZnO Nanoparticles Salt Precursors on Structural, Morphological, Optical and MB Photocatalytic Properties Using Hydrothermal Synthesis
No Thumbnail Available
Date
2023-03-30
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
Zinc oxide ZnO nanoparticles were successfully produced via a simple low cost
hydrothermal method using different metal precursors. Zinc acetate Zn(CH3COO)2, Zinc nitrate
(Zn(NO3)2) and Zinc chloride (ZnCl2) were the source materials. The obtained nanoparticles were
investigated by means: X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and
Differential Reflectance spectroscopy (DRS). The XRD exhibited the high crystallinity of the pure
ZnO phase with hexagonal wurtzite crystalline structure for all simples excepted for ZnO
synthetized from ZnCl2 precursor. The crystallite sizes were estimated in the range of 20-37 nm.
The precursor type does not affect the Eg of the nanoparticles. The bandgaps energies were between
3.21-3.22eV. The type of precursor affect the particles morphology. SEM images reveal different
morphologies. The photocatalytic activity of the synthetized ZnO (zinc oxide) ( NPs, in comparison
with that of commercial powder for the methylene blue (MB) degradation under Ultra-Violet (UV)
irradiation, showed the appropriate activity of nanostructures obtained by Zn(NO3)2 and
Zn(CH3COO)2 precursors. The first-order kinetic constant over ZnO from Zn(NO3)2 was 1.9, 3.7
and 1.5 times of ZnO commercial powder, ZnO from ZnCl2 and Zn(CH3COO)2, respectively. The
ZnO NPs from Zn(NO3)2 and Zn(CH3COO)2 precursors have the best photocatalytic degradation
performance with a degradation rate of 99.3% and 96.4%, respectively. It is found that the higher
photocatalytic performance was probably due to the larger crystallinity, purity phase and specific
morphologies than smaller particle size effect. A decrement in the crystallite size yields in a larger
surface areas and enhances the adsorption of reactants and that paves the way to an enhancement in
the photocatalytic performance. Thus, the synthetized ZnO is nanoparticles by the soft hydrothermal
process which is a promising candidate for the photocatalytic purposes of dyes from waters