介孔电气石/TiO2复合材料的制备及其模拟太阳光光催化性能

采用一步溶胶-凝胶共缩合结合溶剂热合成技术制备出一系列介孔电气石/TiO₂复合材料,表征了复合材料的相结构、形貌、孔隙率、光吸收性质以及组成结构.结果表明:制备的电气石/TiO₂复合材料具有纯锐钛矿晶相、均匀的介孔结构、较大的比表面积(205~242 m²·g^-1)、均匀的孔径分布(3.4~3.8 nm)以及较低的带隙能(3.0 eV).在模拟太阳光照射下,电气石/TiO₂复合材料可以被成功地应用于水中有机污染物罗丹明B和诺氟沙星的降解.降解动力学研究表明:电气石的掺杂提高了TiO₂的光催化量子效率,降低了TiO₂的带隙能.对罗丹明B的降解,电气石掺杂量为1wt%~5wt%的电气石/TiO₂复合材料表现出比纯TiO₂更高的降解速率,对诺氟沙星的降解,电气石/TiO₂复合材料的降解速率高于纯TiO₂的.

Preparation of mesoporous tourmaline / TiO2 composites and their simulated sunlight photocatalytic activity

A series of mesoporous tourmaline/TiO₂ composites were prepared by using one-step sol-gel co-condensation combined with solvothermal synthesis technique, and their phase structure, morphology, porosity, optical absorption property, as well as composition and structure were characterized. The results show that the tourmaline/TiO₂ composites exhibit pure anatase crystalline phase, uniform mesostructure, large surface area (205-242 m²·g^-1), uniform pore size distribution (3.4-3.8 nm) and low band gap energy (3.0 eV). The as-prepared composites were successfully applied to the degradation of aqueous organic pollutants rhodamine B and norfloxacin under simulated sunlight irradiation. The degradation kinetics researches show that, the addition of tourmaline improves the photocatalytic quantum efficiency of TiO₂ and reduces the band gap energy of TiO₂. The composites with 1wt%-5wt% tourmaline loading exhibit the higher rates to the rhodamine B degradation and the degradation rates of tourmaline/TiO₂ composites to the norfloxacin are higher than that of the pure TiO₂.