Ce-La-Ag共掺杂TiO2/玄武岩纤维复合光催化剂的制备和性能

以玄武岩纤维(BF)为载体,用溶胶凝胶法将Ce-La-Ag共掺TiO₂负载于BF上制备出Ce-La-Ag共掺杂TiO₂/玄武岩纤维复合光催化剂。用光催化降解氨氮废水,研究了烧结温度和废水的pH值对Ce-La-Ag-TiO₂/BF光催化活性的影响。结果表明：Ce-La离子与纳米Ag颗粒的协同作用使TiO₂的禁带宽度由3.2 eV降至2.15 eV。Ce-La-Ag-TiO₂的光催化活性优于纯TiO₂、Ag-TiO₂和Ce-La-TiO₂,负载到BF使其光催化活性进一步提高。当复合光催化剂的烧结温度为600 ℃、氨氮废水的pH值为10.5、模拟可见光的照射时间为360 min时,Ce-La-Ag-TiO₂/BF对氨氮废水重复降解5次的降解率仍高于88.2%。

Fabrication and Photocatalytic Properties of Ce-La-Ag Co-doped TiO2/Basalt Fiber Composite Photocatalyst

The composite photocatalyst of Ce-La-Ag-TiO₂/BF (basalt fiber) was prepared by coating the Ce-La-Ag co-doped TiO₂ onto BF via sol-gel method. The effect of the calcination temperature of the composite photocatalyst and the pH value of wastewater on the photocatalytic activity of these photocatalysts was evaluated by examining the degradation rate of ammonia-nitrogen wastewater. The results show that the coupling effect of Ce-La ion and Ag nanoparticles results in the decreases of the band gap of TiO₂ from 3.2 eV to 2.15 eV, with a photocatalytic activity obviously higher than those of the pure TiO₂, Ce-La-TiO₂ and Ag-TiO₂. Moreover, the catalytic activity of Ce-La-Ag-TiO₂ is further improved after being deposited onto BF. When the calcination temperature for the Ce-La-Ag-TiO₂, pH of wastewater and irradiating time of simulate visible light are 600^oC, 10.5 and 360 min, respectively, the resulted degradation rate of ammonia nitrogen wastewater can still reach above 88.2% after repeated use of the composite photocatalyst for five times.