Photocatalytic degradation of dodecyl-benzenesulfonate over TiO2-Cu2O under visible irradiation.

A series of TiO(2)-Cu(2)O mixed oxides were prepared by the hydrolysis of titanium butoxide and reduction of copper acetate with hydrazine. These composite oxides were characterized by X-ray diffraction (XRD), inductively coupled plasma spectrometry (ICP), high-resolution transmission electron microscopy (HRTEM), N(2) adsorption and UV-vis techniques. Photocatalytic degradation of dodecyl-benzenesulfonate (DBS) under visible irradiation was performed, and effects of composition of catalysts and reaction conditions were studied. It was observed that TiO(2)-Cu(2)O composite oxides exhibited better photocatalytic activity than Cu(2)O or TiO(2) alone. Among these composite oxides, the 5%TiO(2)-Cu(2)O displayed the highest activity, and the degradation percentage of DBS and COD reached 97.3% and 65%, respectively. In addition, it was found that the decomposition of DBS followed the first-order kinetics and the adsorption of DBS followed the Langmuir model. Oxygen in solution played a vital role in the elimination of COD.