煅烧温度及气氛对GdBr_3掺杂TiO_2粉体可见光光催化活性的影响

EFFECTS OF CALCINATION TEMPERATURE AND TMOSPHERE ON THE VISIBLE LIGHT PHOTOCATALYTIC ACTIVITY OF GdBr_3-DOPED TiO_2

采用醇盐水解法制备了掺杂GdBr3改性的纳米TiO2光催化复合材料,采用X射线衍射、透射电子显微镜、表面及孔隙度分析仪等测试技术分析和研究了改性TiO2粉体的晶相组成、形貌、比表面积及可见光光催化活性。结果表明,改性TiO2粉体在N2环境中经550℃煅烧2h后,粉体分散较好,TiO2仍为锐钛矿相,GdBr3/TiO2(摩尔比)为0.05的改性粉体在波长为420nm,照度为1200μw/cm2的可见光下照射12h后,对甲基橙的降解率可达70%,呈现出较好的可见光光催化活性。

The GdBr3-doped nano-TiO2 photocatalysts were prepared by alkoxide hydrolysis. The crystal phase composition, morphologies and specific surface area of the modificated TiO2 powder were analyzed by X-ray diffraction （XRD）, transmission electron microscope （TEM） and Brunner-Emmett-Teller （BET）. The results show that the GdBr3-doped TiO2 calcined at 550℃ for 2h in nitrogen were anatase in structure and dispersed evenly. With the conditions that the molar ratio of GdBr3 to TiO2 was 0.05, the exposure to visible light at the wavelength above 420nm was for 12h and the illumination intensity was 1200μw/cm2, the photocatalytic degradation of methyl orange was 70%, which indicated that photocatalytic activity of such TiO2 powder was more active.