Photocatalytic oxidation removal of fluoride ion in wastewater by g-C3N4/TiO2 under simulated visible light

As a highly active photocatalyst, g-C 3 N 4 /TiO 2 heterojunction nanocomposites were in situ synthesized by hydro-thermal method and calcination using melamine as precursors. The morphology and chemical structure of the prepared photocatalysts were characterized by X-ray diffraction, Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), SEM, UV-vis, and photoluminescence analysis (PLA). At last, the photocatalytic activities of g-C 3 N 4 /TiO 2 nanocomposites to remove fluoride under simulated visible light were evaluated. Results showed that the fluoride removal rate of the prepared g-C 3 N 4 /TiO 2 was about three times than pure g-C 3 N 4 due to the rapid charge transfer and the efficient separation of photogenerated electron-hole pairs in heterojunctions between g-C 3 N 4 and TiO 2 . Graphical abstract Heterojunction g-C 3 N 4/ TiO 2 display the excellent fluoride removal rate due to the rapid charge transfer and efficient separation of electron-hole pairs.