Zn-TiO2/AC photocatalysts for pollutants degradation from experimental and DFT studies

The massive emission of dye wastewater has caused significant environmental problems. In this study, zinc-doped titanium dioxide loaded on biochar was synthesized by a simple solvothermal method to investigate its ability of degradation for dyes in photocatalytic process. The discussion focused on the impact of unactivated, acid-activated, and alkali-activated biochar on the properties of composites. Additionally, the composite catalysts underwent comprehensive physical and chemical characterization. The results showed that the particle size of Zn-TiO 2 OHAC increased significantly, which improved the sedimentation performance. Zn-TiO 2 OHAC demonstrated exceptional photocatalytic efficiency in the degradation of various pollutants such as Rhodamine B, Congo Red, Methyl Orange, and Methylene Blue. The better performance of the alkali-treated biochar-loaded composite catalysts was attributed to the fact that the alkali-treated biochar changed the electronic structure of the loaded materials and contained more carbon-oxygen functional groups, which was favorable for the separation of electrons and holes.