Preparation of spherical activated carbon-supported and Er^(3+):YAlO_3-doped TiO_2 photocatalyst for methyl orange degradation under visible light  

球形活性炭负载和Er^(3+):YAlO_3掺杂TiO_2的制备及其在可见光下降解甲基橙(英文)

作　　者：董双石[1] 张建宾[1] 高琳琳[1] 王艳龙[1] 周丹丹[1] 

机构地区：[1]吉林大学地下水资源与环境教育部重点实验室,长春130021

出　　处：《Transactions of Nonferrous Metals Society of China》2012年第10期2477-2483,共7页中国有色金属学报（英文版）

基　　金：Projects (50908096, 50908097) supported by the National Natural Science Foundation of China;Project (20100471251) supported by China Postdoctoral Science Foundation

摘　　要：In order to develop the high photocatalytic activity of TiO2 under visible light as that under ultraviolet light and make it easy to be separated from treated liquor, a visible light response and spherical activated carbon （SAC） supported photocatalyst doped with upconversion luminescence agent Er3＋：YAlO3 was prepared by immobilizing Er3＋：YAlO3/TiO2, which was obtained by combination of Er3＋：YAlO3 and TiO2 using sol-gel method, on the surface of SAC. The crystal phase composition, surface structure and element distribution, and light absorption of the new photocatalysts were examined by X-ray diffraction （XRD）, energy dispersive X-ray spectra （EDS） analysis, scanning electron microscopy （SEM） and fluorescence spectra analysis （FSA）. The photocatalytic oxidation activity of the photocatalysts was also evaluated by the photodegradation of methyl orange （MO） in aqueous solution under visible light irradiation from a LED lamp （λ400 nm）. The results showed that Er3＋：YAlO3 could perform as the upconversion luminescence agent which converts the visible light up to ultraviolet light. The Er3＋：YAlO3/TiO2 calcinated at 700 °C revealed the highest photocatalytic activity. The apparent reaction rate constant could reach 0.0197 min-1 under visible light irradiation.为使TiO2能够在可见光下发挥其于紫外激发下的高光催化活性,且易于从处理废水中分离,采用溶胶-凝胶法将TiO2与掺杂稀土离子Er3+的上转换发光剂Er3+:YAlO3结合,再将其负载到球形活性炭(SAC)表面,制备出可见光响应的负载型Er3+:YAlO3/TiO2-SAC光催化剂。通过XRD、EDS、SEM与FSA等手段对制备的光催化剂进行晶相、表面结构与元素分布、发光光谱等表征。以甲基橙为目标污染物,研究制备的光催化剂在可见光下的催化活性。结果表明,Er3+:YAlO3可以作为上转换发光材料,它吸收可见光并发射紫外光进而激发TiO2。700°C煅烧制备的催化剂具有最佳的光催化活性,可见光下表观反应速率常数可达0.0197min-1。

关 键 词：visible light upconversion luminescence TiO2 activated carbon PHOTOCATALYSIS 

分 类 号：O643.3[理学—物理化学]