Effect of different Bi/Ti molar ratios on visible-light photocatalytic activity of BiOI/TiO2 heterostructured nanofibers

Abstract In this study, bismuth oxyiodide/titanium dioxide (BiOI/TiO 2 ) heterostructures with different molar ratios of Bi and Ti were synthesized by electrospinning and hydrothermal methods. The samples thus synthesized were characterized by powder X-ray diffraction, scanning electron microscopy, transmission electron microscopy (TEM), high-resolution TEM, X-ray photoelectron spectroscopy, and ultraviolet–visible diffuse reflectance spectroscopy. The results confirmed the presence of the BiOI/TiO 2 heterojunction with Bi/Ti molar ratios of 0.20–1 by electrospinning and hydrothermal methods. Photocatalytic activity was also evaluated by the degradation of methylene blue (MB) under visible-light irradiation. The 80% BiOI/TiO 2 heterostructure exhibited the best photocatalytic activity for the degradation of MB under visible-light irradiation.