Sol–gel Grown Fe-doped ZnO Nanoparticles: Antibacterial and Structural Behaviors

Iron (Fe) doped Zinc-oxide (ZnO) nanoparticles (NPs) with composition Zn1-xFexO, where x =
0.0, 0.01, 0.03, and 0.05 are synthesized by sol–gel method from nitrate precursors and gelatin at
fixed calcination temperature of 650 °C maintained for 2 h. The effects of Fe contents on the
antibacterial and structural features of these NPs are inspected. Prepared NPs are characterized
via X-ray diffraction (XRD) and scanning electron microscopy (SEM). XRD patterns display the
single crystalline nature of samples that exists in hexagonal wurtzite phase. SEM images reveal
the existence of nearly spherical shaped single-crystalline NPs. A quantitative analysis of the size
dependent strain effects is performed through Williamson-Hall and size-strain plot and its impact
of strain on peak broadening is demonstrated. The values of strain, stress, and energy density are
calculated. The estimated NPs mean size from FESEM and size-strain plot (SSP) is found to be
in close agreement. ZnO NPs in the presence of Fe show great inhibition towards E. coli
bacterial growth. It is asserted that, Fe acting as impurity in the ZnO nanostructure enhances the
power oxidation of ZnO which results an augmentation of antimicrobial activity.
Keywords: ZnO, lattice strain, crystallite size, antibacterial activity, E. coli