Synthesis and enhanced visible-light photocatalytic activity of anatase TiO2/sludge-derived activated carbon composite for degradation of methylene blue

In order to enhance visible-light photocatalytic activity, anatase TiO 2 was modified with sludge-derived activated carbon (SDAC) through the physical mixing and hydrothermal method, respectively. The activated carbon was prepared from sewage sludge by molten salt method. Under visible light irradiation, the removal of methylene blue (MB) with a concentration of 40 mg L -1 by TiO 2 -SDAC synthesized through the physical mixing and hydrothermal method were up to 70.13% and 95.48%, respectively. Characterization results revealed that a Ti-C bond was formed on the surface of TiO 2 -SDAC. Under physical mixing and hydrothermal treatment, carbon atoms can be introduced into the TiO 2 lattice, resulted in tuning the band gap of TiO 2 and extending its optical response to the visible-light region. The photocatalytic degradation of MB was fitted well with Elovich model. It can be concluded that SDAC adsorbs, supports and enhances the photocatalytic activity of TiO 2 .