双稀土共掺杂TiO_2纳米材料的制备及其性能研究

The Synthesis of TiO_2 Nano Materials with Bi-rare Earth Ion Doping and the Study of Their Properties

采用溶胶-凝胶法制备了系列Eu3+和La3+双稀土离子共掺杂的TiO2纳米材料,通过X射线衍射、扫描投射电镜和荧光光谱分析对样品进行表征.结果表明,Eu3+和La3+双稀土离子共掺杂比Eu3+或La3+单组分掺杂能够更加有效地抑制TiO2纳米晶体的晶相转变,得到的球形纳米粉体颗粒尺寸为10～20nm;Eu3+和La3+双稀土离子共掺杂的TiO2纳米体系均能得到Eu3+的特征发射光谱,并且在稀土总含量不变的情况下,以少量La3+替代Eu3+时,Eu3+的发光性能变得更强,即TiO2纳米体系中La3+对Eu3+的发光具有一定的敏化作用;以甲基兰溶液为目标污染物,考察Eu3+和La3+双稀土离子共掺杂的TiO2纳米材料的光催化活性,结果表明Eu3+和La3+双稀土离子共掺杂比单组分掺杂能更有效地提高TiO2纳米材料的光催化活性,在该体系中Eu3+和La3+的最佳比例为1∶4.

In the paper, a series of Eua＋ and La3＋ doped TiO2 nanoparticles were prepared by sol-gel method and characterized by means of XRD, SEM and photoluminescence （PL） spectra. The catalytic activity was tested for the degradation of methyl blue solution. The results showed that the doping of Eu3＋ with La3＋ together could inhibit the phase transformation of nano TiO2 with particle size of 10~20 nm. The system with doping of Eu3＋ and La3＋ could get the characteristic spectra and the intensity of Eu3＋ characteristic spectra increased with the La3＋ replacing Eua＋ ,which implied sensitization effect of Laa＋ in the TiO2 system. The activity results indicated that the doping of Eu3＋ with La3＋ together could increase the photo catalytic activity and the best ratio of Eu3＋ ： La3＋ is 1 ： 4.