Ultrasonic-assisted synthesis of doped TiO2 nanocomposites: Characterization and evaluation of photocatalytic and antimicrobial activity

TiO2 nanocomposites doped with Al2O3, Bi2O3, CuO and ZrO2 were synthesized by using sonochemical method. The synthesized nanocomposites have been characterized by X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray (EDX) spectra, Diffuse Reflectance Spectroscopy (DRS), Fourier Transform Infra-Red spectroscopy (FT-IR), FT-Raman Spectroscopy (FT-Raman) and Thermo Gravimetric-Differential Thermal Analysis (TG-DTA). Solar light photocatalytic activity of the composite samples was investigated by using methyl orange, methylene blue and rhodamine B dyes as an organic pollutants. The results showed that the Bi2O3 – TiO2 nanocomposite is more efficient toward the degradation of the dyes under solar light and TiO2 is the least efficient catalyst and the efficiency is almost in order; Bi2O3 –TiO2 > Al2O3 – TiO2 > CuO – TiO2 > ZrO2 – TiO2 > TiO2. Furthermore, the antibacterial activity of the nanocomposites was tested against gram negative bacteria (Escherichia coli). Among the five nanocomposites, Al2O3 – TiO2 shows some significant zone of inhibition around the film under dark condition.