Photocatalytic oxidation of acetaminophen using carbon self-doped titanium dioxide

A new carbon self-doped (C-doped) TiO2 photocatalyst was synthesized by solegel method, in which titanium butoxide was utilized because of its dual functions as a titanium precursor and a carbon source. The effects of calcination temperature from 200 to 600 degrees C on the photocatalytic activity towards acetaminophen (ACT, which was used as a model persistent organic pollutant) under visible light were examined. The effects of temperature on the structure and physicochemical properties of the C-doped TiO2 were also investigated by X-ray diffraction, BET measurement, X-ray photoelectron spectroscopy, and scanning electron microscopy. The specific surface area of the as-doped TiO2 declined as the crystal size increased with increasing calcination temperature. Only amorphous TiO2 was present at 200 degrees C, while an anatase phase was observed between 300 and 500 degrees C. Both anatase and rutile phases were observed at 600 degrees C. Photocatalytic activity increased as the calcination temperature initially increased from 200 to 300 degrees C but it decreased as the calcination temperature further increased from 400 to 600 degrees C. The highest ACT removal of 94% with an apparent rate constant of 5.0 x 10(-3) min(-1) was achieved using the new doped TiO2 calcined at 300 degrees C, which had an atomic composition of 31.6% Ti(2)p(3), 50.3% O1s and 18.2% C1s. (C) 2016 Chinese Institute of Environmental Engineering, Taiwan. Production and hosting by Elsevier B.V.