Selective uptake of cationic dyes by microemulsion driven Ag2O/TiO2 nanocomposites

In this study, Nanocomposites (NCs) of silver oxide (Ag 2 O) and Titanium dioxide (TiO 2 ) of various combinations Ag 2 O/TiO 2 (5 mM: 1 mM), Ag 2 O/TiO 2 (1 mM: 5 mM) and Ag 2 O/TiO 2 (1 mM: 1 mM) were prepared by the microemulsion method. Batch adsorption experiments were conducted to evaluate the adsorption of hazardous dyes such as crystal violet (CV), methyl orange (MO), and methylene blue (MB) in various combinations. The selective adsorption of dyes under the influence of both concentration and temperature was monitored and observed that up to 90–93% of CV, MO, and MB were removed, when the maximum concentrations of CV: MO: MB were (10: 10: 50), (10: 50: 10) and (50: 10: 10) respectively. The adsorption data were fitted to Langmuir, Freundlich and Temkin isotherms, however, based on R 2 value, Freundlich model was found suitable indicating that maximum adsorption of dyes was taken place at lower temperature which exhibited the exothermic nature of the process. Prior to the sorption study, the prepared nanostructures were characterized by X-ray diffraction (XRD), Zeta potential, Fourier transforms infrared (FTIR) spectroscopy, UV–Visible spectroscopy, field emission scanning electron microscopy (FESEM) and energy dispersive X-ray spectroscopy (EDS). The diffraction patterns confirmed the structural formation of Nanocomposites and the average crystallite sizes for Ag 2 O/TiO 2 (5 mM: 1 mM), Ag 2 O/TiO 2 (1 mM: 5 mM) and Ag 2 O/TiO 2 (1 mM: 1 mM) were calculated to be 23, 27, and 50 nm respectively.