The photocatalytic antibacterial behavior of Cu-doped nanocrystalline hematite prepared by mechanical alloying

Abstract

To improve the photocatalytic properties of hematite (Fe2O3), we take the merit of nanoscale and exploit a mechanical alloying (MA) method for Cu doping with various weight percentages (1, 3, 5, and 10). Our techniques to evaluate the phase and morphological characterization of the prepared nanoparticles were, respectively, X-ray diffraction (XRD) and field-emission scanning electron microscopy (FESEM). The elemental analysis and elemental distribution map were examined by energy dispersive X-ray spectroscopy (EDS). Furthermore, we utilized Fourier transform infrared (FTIR) analysis and ultraviolet–visible diffuse reflectance spectroscopy (UV–Vis DRS) for appraisal of Fe–O and Cu–O bonds and band gaps. Then we investigated the photocatalytic activity based on methylene blue (MB) photodegradation under irradiation of 300 W Xenon lamp and finally explored the antibacterial behavior against Escherichia coli (E. coli). The UV–Vis DRS results indicated reduction of band gap in the Cu-doped hematite nanoparticles. For the samples considered here, the sample with 5 wt.% of the dopant showed the lowest band-gap, 1.57 eV. It also decomposed 92.5% of MB from the wastewater under the Xenon-lamp irradiation during 120 min, and had the highest rate of disinfection with > 99.99% of bacterial removal in 360 min. Low band gap, substantial sunlight absorption, efficient MB removal, and high antibacterial activity are some suitable photocatalytic properties specifically achieved in this work.