Hybrid Material TiO2-TPA@porous Activated Carbon and Its Activity in the Photocatalytic Degradation of Pharmaceutical Pollutants in Water

Abstract

The next generation of photocatalysts should exhibit visible-light absorption, high pollutant adsorption capacity, and stability. The activated carbons (AC) obtained from sustainable procedures, such as the pyrolysis of agroindustrial residues, show high adsorption capacities and an interesting ability to photoinduce reactive oxygen species (ROS). For this reason, herein, the synthesis of a hybrid TiO₂-TPA@AC material consisting of a UV–visible-light active photocatalyst as the TiO₂-TPA and an AC obtained from the pyrolysis of H₃PO₄-activated sunflower seed shells (SSS) is reported. TiO₂-TPA@AC photocatalytic activity was evaluated under simulated sunlight irradiation to oxidize ibuprofen (IB) and diclofenac (DI) in water, finding that the hybrid material exhibited the highest removal of both pollutants (98%) after 1 h through a dark adsorption step and, by a photoinduced process, where both the TiO₂-TPA and the AC generated ROS able to oxidize 95% of the adsorbed pollutants. The adsorption–photooxidation capacity of the TiO₂-TPA@AC material was stable after four reusing cycles, leaching Ti and W in solution at concentrations of 0.48 and 0.31 mg L^–1, respectively.