SYNTHESIS AND CHARACTERIZATION OF Fe–ZnO THIN FILMS FOR ANTIMICROBIAL ACTIVITY

Abstract

Pure and Fe-doped zinc oxide (ZnO) sol–gel thin films were deposited by spin-coating process. Pure ZnO and Fe–ZnO films, containing Fe of 2–8[Formula: see text]wt.%, were annealed at 500∘C for 2[Formula: see text]h. All prepared thin films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM) and UV–visible (UV–vis) spectroscopy. XRD studies show the polycrystalline nature with hexagonal wurtzite structure of pure ZnO and Fe–ZnO thin films. The crystallite size of the prepared samples reduced with increasing Fe doping concentrations. AFM and SEM results indicated that the average grain size decreased as Fe doping concentration increased. The transmittance spectra were then recorded at wavelengths ranging from 300[Formula: see text]nm to 1000[Formula: see text]nm. The films produced yielded high transmission at visible regions. The optical bandgap energy of spin-coated films also decreased as Fe doping concentration increased. In particular, their optical bandgap energies were 3.75, 3.6, 3.5, 3.45 and 3.3 eV at 0-, 2-, 4-, 6- and 8-wt.% Fe concentrations, respectively. Antibacterial activities of pure ZnO and Fe–ZnO against E. coli and S. aureus were evaluated by international recognized test (JIS Z 2801). The results showed that pure and Fe-doped ZnO thin films have antibacterial inhibition zone against E. coli and S. aureus. Gram-positive bacteria seemed be more resistant to pure and Fe-doped ZnO thin films than gram-negative bacteria. The test shows an incremental increase in antibacterial activity of the thin films when dopant ratio increased under UV light.

Tuning of Photoluminescence and Antibacterial Properties of ZnO Nanoparticles through Sr Doping for Biomedical Applications

“…AL-Jawad et al observed a similar enhancement of antibacterial activity against S. aureus and E. coli in Ag-doped ZnO thin films [31]. Fe-doped ZnO thin films also exhibited a better antibacterial response under UV light irradiation against S. aureus and E. coli [32].…”

Characterization of Treated Multi-Walled Carbon Nanotubes and Antibacterial Properties

“…It observes that the average crystal size of the R-MWCNTs and F-MWCNTs are about (3.27 and 3.19) nm, respectively. the average crystal size of high intensity peaks calculated from the Scherer's equation ( 1) is about 25.43 nm [19][20][21].…”

X-ray and UV Irradiation-Induced Reactive Oxygen Species Mediated Antibacterial Activity in Fe and Pt Nanoparticle-Decorated Si-Doped TiCaCON Films

“…It should be noted that a correct comparison of the bactericidal efficacy of various materials with Fe nanoparticles is almost impossible due to the difference in many key parameters: the film elemental and phase composition, the Fe loading dose, the degree of Fe nanoparticle oxidation and the type of their agglomeration, the irradiation time and power of the source used, as well as the type of used bacterial cultures and their initial concentration. In terms of bactericidal efficiency, the Fe/TiCaSiCON films (100% reduction in CFUs after 8 h) outperform many other systems, for example, Fe/ZnO and Fe/TiO 2 films. Note that the above-mentioned Fe/ZnO and Fe/TiO 2 samples were tested according to the protocol providing for the UV irradiation of a sample with a bacterial suspension on the surface, which could lead to overestimated bactericidal effect.…”