钒掺杂纳米二氧化钛的制备及光催化活性研究  

Preparation and Photocatalytic Activity of Vanadium-doped Nano-TiO_2

作　　者：陈桂华[1] 梁华定[1] 葛昌华[1] 韩德满[1] 王芳[1] 杨辉[2] 

机构地区：[1]台州学院医药化工学院,临海317000 [2]浙江大学纳米科学与技术中心,杭州310027

出　　处：《人工晶体学报》2010年第5期1243-1248,1260,共7页Journal of Synthetic Crystals

基　　金：浙江省自然科学基金项目资助(Y405377);浙江省教育厅项目(Y200906690)

摘　　要：以钛酸四丁酯为钛前驱体,偏钒酸铵为掺杂离子给体。采用溶胶-凝胶法制备了V掺杂纳米二氧化钛粉体;并使用TGA-DSC、XRD、BET、SEM对其晶化温度与结构进行了表征。结果表明:V掺入促进锐钛矿相向金红石相转变、抑制晶粒长大、增大比表面积,纳米粉体颗粒呈分布较均匀的类球形晶粒。以亚甲基蓝为模型反应,考察了V掺杂量、煅烧温度对催化剂光催化性能的影响,结果表明:V掺杂的TiO2粉体降解亚甲基蓝符合一级反应动力学规律;晶格中V4+能够作为电荷转移物种,有效的抑制光生电子与空穴的复合,增加了表面空穴浓度,提高TiO2纳米粉体的光催化活性,当掺杂量为1.5 mol%,煅烧温度为450℃时,TiO2具有最佳的光催化性能。The V-doped TiO2 nanoparticles were prepared by sol-gel method,using tetrabutyl titanate as Ti-precursor,ammonium metavanadate as doping-ion donor.The crystallization temperature and structure of the photocatalyst were characterized via thermogravimtry-differential scanning calorimetry（TGA-DSC）、X-ray diffraction（XRD）,specific surface area analysis（BET） and scanning electron microscopy（SEM）.The results show that V doping leads to crystal lattice distortion,promotes the phase transformation from anatase to rutile of TiO2,inhibits the growth of grain size and enlarges specific surface area.The nanoparticles is uniform and similar spherical.The photocatalytic activity was evaluated by the decomposition of methylene blue.The influence of V-doped concentration and calcined temperature on the activity has been discussed.It was found that the degradation of methyl bule on V-doped TiO2 nanoparticles follows first-order kinetics.V^4＋ in the lattice serves as charge transfer species,thus the recombination of the photon photon-induced electron-hole pair is suppressed more efficiently,and more holes can reach surface to cause oxidation reaction,and enhances the photocatalytic activity of TiO2 nanoparticles.The nanoparticles of 1.5 mol% V-doped TiO2 and calcined at 450 ℃ hold the best photocatalytic activity.

关 键 词：溶胶-凝胶法 二氧化钛 光催化降解 

分 类 号：O648[理学—物理化学]