静电自组装制备镧掺杂高岭石基纳米TiO_2光催化材料研究  

Preparation of Kaolinite-based La-doped Nano Titanium Dioxide Photocatalysts by Electrostatic Self Assembly Method

作　　者：王程[1,2] 施惠生[1] 李艳[2] 杜国强[2] 

机构地区：[1]同济大学先进土木工程材料教育部重点实验室,上海200092 [2]石家庄经济学院材料科学与工程研究所,石家庄050031

出　　处：《人工晶体学报》2010年第6期1381-1385,1395,共6页Journal of Synthetic Crystals

基　　金：河北省自然科学基金(E2008000537);河北省自然科学基金-钢铁联合基金(E2009000946);河北省科学技术研究与发展指导计划项目(07215156)

摘　　要：采用静电自组装方法制备了镧掺杂高岭石基纳米TiO2光催化材料。采用巯丙基三甲氧基硅烷偶联剂对高岭石进行干法改性,采用30%H2O2/HOAc将偶联剂巯基基团氧化为磺酸基基团。在静电引力的作用下,带负电荷的高岭石与带正电荷的钛聚合阳离子和La3+自发地组装在一起,经一定温度热处理得到镧掺杂高岭石基纳米TiO2光催化材料。采用XRF、XRD、FT-IR、SEM和PL等对材料进行分析,采用甲基橙染料评价材料的光催化性能。研究表明:采用静电自组装方法可有效提高高岭石与纳米TiO2的复合效率;镧掺杂导致TiO2与高岭石之间的结合力增强;适量的镧掺杂导致锐钛矿晶体发生畸变,能带结构改变,电子-空穴对复合几率降低,进而导致其光催化性能增强;镧掺量5 mol%的复合材料对甲基橙溶液表现出更高的光催化脱色效果。Kaolinite-based La-doped nano TiO2 photocatalyst was prepared by electrostatic self assembly（ESAM） method.（CH3O）3Si（CH2）3SH silane was modified on the surface of kaolinite by dry process.Sulfhydryl group（-SH） of the silane was oxidized to easy ionized sulfonyl（-SO3H） by 30%H2O2/HOAc oxidant.The electronegative kaolinite self-assembled with titanium polycation and La3＋ on the effect of electrostatic attraction to obtain kaolinite-based La-doped nano TiO2 photocatalysts.The materials were characterized by XRF,XRD,FT-IR,SEM and PL.Methyl orange（MO） was used to estimate the photocatalysis of the material.The results show that the composite efficiency of kaolinite and TiO2 prepared by ESAM method is higher than the traditional method.La-doping can enhance the binding force of TiO2 and kaolinite.Appropriate amount of La doping can reduce the recombination of photogenerated electrons-holes and improve the photocatalytic activity of the photocatalyst.The photocatalytic activity of the 5 mol% La-doped sample is higher than the other samples.

关 键 词：静电自组装 镧掺杂 高岭石 纳米TiO2 光催化 

分 类 号：O543.36[理学—物理]