Spectacular photocatalytic activity of mechanosynthesized heterostructured Bi-Fe-O nanocomposites in wastewater treatment containing colored and colorless pollutants

Abstract Heterostructured Bi-Fe-O (BFO) nanocomposites have been successfully synthesized by ball milling mechanosynthesis process followed by sintering at elevated temperatures. Different structural and microstructural properties of as-synthesized nanocomposites are characterized by the Rietveld refinement of XRD data and analyzing FESEM and TEM images. Diffused UV‐Visible spectra analysis reveals the bandgap energy and surface/grain boundary defects trapped in the samples. The photocatalytic activities and quantum efficiencies of heterostructured BFO nanocomposites are investigated by the successive absorption of Rhodamine B (RhB) dye as a model organic pollutant and colorless pollutant Kanamycin under visible light irradiation. The EDX spectrum and the recyclability test of the milled and sintered samples ensure the reusability of BFO as a potential catalyst. The evaluation of OH radicals of the as-milled nanocomposites has been analyzed by PL spectra using terephthalic acid as a probing molecule. The scavenger test establishes the photocatalytic mechanism of the heterostructured nanocomposite. The enhanced photocatalytic degradation of ~96% RhB within 360 min, ~100% degradation in 300 min with the addition of small of H2O2, and ~90% degradation of colorless antibiotic Kanamycin within 240 min have established the heterostructured BFO nanocomposites as a promising visible-light photocatalyst in wastewater treatment containing organic dye and dissolved antibiotics.