Synthesis, characterization of BiOI/rGO nanocomposite and its photocatalytic functionality analysis under visible light

[Display omitted] •BiOI /rGO nanocomposite was synthesized by hydrothermal method.•The band gap of BiOI/rGO was relatively deceased (1.66 eV) compared to BiOI (1.90 eV) promoting the formation electron-hole pair under the visible light irradiation.•The photocatalytic activity of BiOI, and BiOI/rGO for the degradation of MB was about 68 % and 92 %, respectively for a period of 60 min.•The observed degradation efficiency of the BiOI/rGO binary nanocomposite exhibited 91%, 90%, 90% and 88% efficiency for 2nd, 3rd, 4th and 5th cycles, respectively, which confirmed the material stability.•The obtained results in mineralization process showed before (25.73 ppm) and after (13 ppm) MB dye degradation.•˚OH– species were active species during the photocatalytic activity and were responsible for degradation as confirmed from Scavenger analysis. Visible light responding pristine BiOI and BiOI/rGO nanocomposites were prepared using hydrothermal method. The physicochemical characteristics of BiOI and BiOI/rGO composite were studied through X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FE-SEM), high resolution transmission electronmicroscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy and UV–vis diffuse reflectance spectroscopy (UV–vis-DRS) techniques. The photocatalytic performance of the synthesized material was analysed against Methylene Blue dye. The photocatalytic activity of BiOI, and BiOI/rGO revealed the degradation of MB about 68 % and 92 %, respectively for a period of 60 min which indicated the enhancement of degradation efficiency for BiOI/rGO compared to BiOI.