铁掺杂TiO_2-SBA-15催化剂制备及光催化降解甲基橙研究

采用溶胶-凝胶法,将TiO_2负载到介孔分子筛SBA-15上,再通过FeCl3浸渍的方法,将不同量的铁掺杂到TiO_2-SBA-15上.通过FT-IR、XRD、N2吸附-脱附和TEM等手段对铁掺杂TiO_2-SBA-15催化剂进行表征.结果表明:负载TiO_2后的SBA-15依然为高度有序的二维六方结构,比表面积略有减小,说明SBA-15的孔道结构有利于TiO_2的分散.掺铁后的TiO_2-SBA-15的结构改变不大,且TiO_2晶形仍为锐钛矿型.最后以光催化降解甲基橙探究不同铁掺杂量的TiO_2-SBA-15催化活性.结果表明:铁离子掺杂量为0.035%(质量分数),紫外光照射200min时,甲基橙降解率达最高值98.2%.

Research on preparation of iron doped TiO 2-SBA-15 catalyst and photocatalytic degradation of methyl orange

By sol-gel method TiO 2 is loaded on mesoporous molecular sieve SBA-15. The catalysts which have different contents of iron, are obtained by impregnating FeCl 3 onto TiO 2-SBA-15. The catalysts are characterized by FT-IR, XRD, N 2 adsorption-desorption and TEM. The characterization results indicate that the TiO 2 loaded SBA-15 still has highly ordered 2-dimensional hexagonal structure and the BET surface area is slightly decreased, which demonstrate that the channel of SBA-15 is beneficial to the scatter of the TiO 2. The structure of TiO 2-SBA-15 has not changed too much after doping with iron. The crystalline form of TiO 2 is still anatase. The catalytic activity of iron doped TiO 2-SBA-15 is investigated by photocatalytic degradation of methyl orange. The photo-catalysis results reveal that when the doped content of iron is 0.035% (the mass fraction) and UV radiation time is 200 min, the degradation rate can reach maximum of 98.2%.