Abstract
ZnO nanoparticles (ZnO-NPs) were synthesized by a straightforward modified thermal method using only one chemical: zinc acetate dihydrate. The process is environmentally safer than other methods because it does not involve other chemicals or a catalyst, acid, or base source. X-ray diffraction analysis indicated that the ZnO-NPs crystallize in the hexagonal wurtzite structure. The UV–vis absorption spectra revealed a marked redshift, which is critical for enhanced photocatalytic activity. We used methylene blue for photocatalytic activity tests and found an excellent degradation percentage (99.7%) within a short time (80 min). The antibacterial activity of the synthesized ZnO-NPs was tested against Escherichia coli at different concentrations of ZnO-NPs. The analysis revealed that the minimum inhibitory concentration (MIC) of the ZnO-NPs against E. coli was 30–50 μg/mL. Our ZnO-NPs were found to be more effective than previously reported ZnO-NPs synthesized via other methods.
Highlights
zinc oxide (ZnO) is a nontoxic semiconductor material with a wide bandgap (3.37 eV) and a high exciton binding energy (60 meV) [1]
The degradation rate at 5, 10, 20, 30, 40, 70, and 80 min was 10.6%, 34.4%, 49.8%, 68.3%, 80.8%, 98.4%, and 99.7%, respectively, for the ZnO nanoparticles (ZnO-NPs). These results indicate that ~50% of the methylene blue (MB) dye was degraded within 20 min and that 99.7% of the MB dye was degraded within 80 min when the ZnO-NPs were used
field-emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM) analyses revealed that the synthesized particles are smooth and spherical, with a nearly aggregated size distribution
Summary
ZnO is a nontoxic semiconductor material with a wide bandgap (3.37 eV) and a high exciton binding energy (60 meV) [1]. ZnO nanoparticles (ZnO-NPs) have been used as, for example, photocatalysts for organic pollutant degradation [2], antibiotics [3,4], electrode materials for solar cells [5], and photoluminescence emitters [6]. Among the many characteristics of ZnO, two of the most interesting are photocatalytic activity and antibacterial activity. Catalysts 2019, 9, 608 such as ZnO and TiO2 , are attractive materials for the degradation of such organic pollutants in the presence of UV light and/or solar radiation [11]. The photocatalytic activity of ZnO is apparently better than that of TiO2 because ZnO exhibits greater electron mobility [12]. Under UV light, the prepared ZnO-NPs show excellent photocatalytic activity toward the degradation of methylene blue (MB). The antibacterial activity of the synthesized ZnO-NPs was tested against Escherichia coli (Gram-negative) pathogenic microbial strain
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
