Synergistic Promotion of Photocatalytic Degradation of Methyl Orange by Fluorine- and Silicon-Doped TiO/AC Composite Material.

The direct or indirect discharge of organic pollutants causes serious environmental problems and endangers human health. The high electron-hole recombination rate greatly limits the catalytic efficiency of traditional TiO-based catalysts. Therefore, starting from low-cost activated carbon (AC), a photocatalyst (F-Si-TiO/AC) comprising fluorine (F)- and silicon (Si)-doped TiO loaded on AC has been developed. F-Si-TiO/AC has a porous structure. TiO nanoparticles were uniformly fixed on the surface or pores of AC, producing many catalytic sites. The band gap of F-Si-TiO/AC is only 2.7 eV. In addition, F-Si-TiO/AC exhibits an excellent adsorption capacity toward methyl orange (MO) (57%) in the dark after 60 min. Under the optimal preparation conditions, F-Si-TiO/AC showed a significant photodegradation performance toward MO, reaching 97.7% after irradiation with visible light for 70 min. Even under the action of different anions and cations, its degradation efficiency is the lowest, at 64.0%, which has good prospects for practical application. At the same time, F-Si-TiO/AC has long-term, stable, practical application potential and can be easily recovered from the solution. Therefore, this work provides new insights for the fabrication of low-cost, porous, activated, carbon-based photocatalysts, which can be used as high-performance photocatalysts for the degradation of organic pollutants.