Gd,B共掺杂改性TiO_2纳米颗粒的可见光光催化活性

Visible photocatalytic activity of TiO_2 nanoparticles co-doped with Gd and B

采用溶胶-凝胶法制备了Gd和B共掺杂的TiO2纳米颗粒,研究了TiO2纳米颗粒在可见光下的光催化活性。应用XRD、TEM和UV-Vis等手段对TiO2纳米颗粒的物相、粒径、形貌及光学性能进行了表征。结果表明,掺杂可以抑制TiO2晶粒增长,阻碍TiO2由锐钛矿相向金红石相的转变。紫外-可见吸收光谱显示,共掺杂纳米颗粒在可见光区吸收有较强提高,共掺杂离子以协同作用拓展TiO2光谱响应,使吸收带产生红移,提高光生载流子的分离效率。光催化降解实验表明,共掺杂TiO2纳米颗粒有很高的可见光光催化活性,以500℃热处理的共掺杂摩尔比为0.005 Gd和0.04 B的TiO2纳米颗粒光催化效果最好,在可见光下对甲基橙的降解率为98.9%。

TiO2 nanoparticles co-doped with Gd and B were prepared by sol-gel method,and its photocatalytic activity was studied with photocatalytic oxidation in visible light.The TiO2 nanoparticles were characterized by XRD,TEM and UV-Vis.The effects of Gd/B doping on the crystal phase,crystallite sizes,surface topography and optical property of the catalysts were investigated.The results exhibited that the Gd/B doping could not only efficiently inhibit the grain growth but also suppress the phase transition of anatase to rutile.UV-Vis spectrum has shown that the TiO2 nanoparticles possesses strong absorption in visible region,for the co-operation effect of elements doped,cause red-shift of the onset of the absorption spectrum,increase the separation of photoinduced charge carriers.And it has also shown the high catalytic activity.The TiO2 nano particles co-doped with mole fraction of 0.005 Gd/0.04B calcined at 500 ℃has shown the highest catalytic activity,and the degradation percent of methyl orange was 98.9%.