BiOCl/AgCl-BiOI/AgI quaternary nanocomposite for the efficient photodegradation of organic wastewaters and pathogenic bacteria under visible light

Sheet-like BiOCl/AgCl-BiOI/AgI quaternary nanocomposites were prepared by a facile single-step co-precipitation method using 1-methyl-3-(oxiran-2ylmethyl)-1H-imidazolium-3-chloride ([MOYI]Cl) ionic liquid (IL) and tetrabuthyl ammonium iodide (TBAI) as Cl and I sources and template agents as well. The products were comprehensively characterized by X-ray diffraction powder (XRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Diffuse Reflectance Spectroscopy (DRS), nitrogen adsorption-desorption isotherms (BET), and Fourier Transform Infrared spectroscopy (FTIR). The XRD pattern well confirmed the presence of BiOX and AgX (X = Cl and I) crystalline phases in the structure. In addition, the SEM micrographs and TEM image indicated that the sample had sheet-like morphology and the thickness was below 100 nm. Photoactivity of the sample was evaluated by photodegradation of Acid Blue 92 (AB92, an azo dye) and 3-methyl-4-nitrophenol (3M4N, from the semivolatile organic compounds (SVOCs) family) aqueous solutions. According to the results, the product was incredibly efficient for the removal of the contaminants during 120 min of the reaction time. Antibacterial experiments were also conducted and the obtained results showed that the prepared nanostructure had high capacity to decrease the concentration of both gram-negative (E. coli) and gram-positive (S. aureus) pathogenic bacteria after 5 h of the treatment time.