Surfactants-assisted preparation of TiO_2-Mn oxide composites and their catalytic activities for degradation of organic pollutant

摘要

The composites of TiO_2 and manganese oxide were synthesized in an aqueous surfactant/cosurfactant solution including Mn salt under basic condition. The morphology and the thickness of Mn oxide introduced on the surface of TiO_2 could be controlled by changing the concentrations of Mn salt, NH_4OH, surfactant, and cosurfactant. Also, the effect of heat treatment on the crystal structure of composite particles was investigated with the variation of calcination temperature. The composites were analyzed by using FE-SEM, TEM, XRD, and EDS. In addition, the catalytic performances of bare TiO_2 and TiO_2-Mn oxide for the degradation of methylene blue (MB) with the assistance of H_2O_2 at 25 C were studied using UV-vis spectrophotometer. The composites with the crystal structures of anatase TiO_2 and Mn_3O_4 having the thicker Mn oxide shell showed the highest catalytic activity for MB degradation among the synthesized catalysts.