Sol–gel grown Fe-doped ZnO nanoparticles: antibacterial and structural behaviors

Abstract

Bacterial resistance to antibiotic treatment is an attractive issue. The discovery of new antibiotics often does not respond to the rapidly increasing bacterial resistance and needs innovative approaches to combat bacterial infections. The NPs size-dependent strong anti-bactericidal effect of Zn1−x Fe x O is inspected. Iron (Fe)-doped zinc-oxide (ZnO) nanoparticles (NPs) with composition Zn1−x Fe x O, 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. XRD patterns display the single-crystalline nature of samples that exist in hexagonal wurtzite phase. SEM images reveal the existence of nearly spherical-shaped single-crystalline NPs. The observed broadening in the X-ray peaks confirms the evolution of crystalline phases in Zn1−x Fe x O 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 some inhibition toward E. coli bacterial growth. Fe acting as impurity in the ZnO nanostructure enhances the power oxidation of ZnO resulting in an augmentation of antimicrobial activity.