掺杂TiO_2纳米线及其可见光催化性能  

Preparation of Transition-metal Ion Doped Titania Nanowires and the Visible Photocatalytic Activity

作　　者：刘祥志[1] 徐明霞[1] 李顺[1] 张念星[1] 

机构地区：[1]天津大学材料学院先进陶瓷与加工技术教育部重点实验室,天津300072

出　　处：《武汉理工大学学报》2007年第10期173-177,共5页Journal of Wuhan University of Technology

基　　金：教育部博士点基金(20030056001)

摘　　要：采用二次阳极氧化工艺制备了高度有序的多孔氧化铝模板,通过模板法与溶胶-电泳沉积法结合的组装技术,合成了具有高比表面积的糖葫芦状M/TiO2(M=Fe3+,Zn2+,Cu2+,Cr3+)纳米线数组体系。采用SEM对样品进行了表征,SEM测试结果表明M/TiO2纳米线数组保持了模板的有序性,直径分布均匀一致,为70 nm左右,长为15μm左右,取向性很好。以甲基橙为目标降解物,在可见光下考察该金属离子掺杂纳米线的催化活性,确定了每种离子的最佳掺杂量。结果显示此掺杂纳米线数组体系具有非常优良的可见光催化性能,这也使得在可见光下纳米线具有更大的应用前景和优势。M/TiO2薄膜的紫外-可见吸收光谱测试结果显示氧化钛的吸收带边红移至了可见光区,并通过相关公式进行了禁带宽度的估算。结合对不同离子掺杂纳米线的可见光催化活性的比较,从不同角度对于过渡金属离子掺杂改性的机理进行了初步探讨。A two-step anodizing process was used to prepare highly ordered porous anodic alumina template （PAA）. The template method was combined with the sol-electrophoresis deposition to prepare M/TiO2 （M = Fe^3＋ , Zn^2＋ , Cu^2＋ , Cr^3＋ ） titania nanowire arrays with the shape of string of candied haws. This type of titania nano-arrays had a high specific surface area. The samples were characterized by scanning electron microscopy （SEM）. According to the photographs of SEM, the nanowires keep the regularity of the template. The diameter of nanowires was uniformly distributed and the nanowires have very good orientation. The diameter of the nanowires was about 70 nm and the length was about 15 μm. The visible photocatalytic activity of M/TiO2 nanowires was characterized by degradation of the methyl orange solution and the best dopping content of each ion was obtained. The results indicated that the M/TiO2 titania nanowire arrays showed excellent visible photocatalytic activity. As a result, the titania nanowire arrays have tremendous application prospect and predominance under visible light. The UV-vis absorption spectrums of M/TiO2 film samples showed that the absorption edge of the UV-Vis spectra shift into visible light region and the band gap values are estimated via correlated formulas. Through comparing the vis-photocatalytic activity of different iondoped nanowires, the transition-metal ion doping mechanisms to achieve the visible-light photocatalytic activities of the TiO2 nanowires are discussed from different views.

关 键 词：溶胶-电泳沉积法 M/TiO2纳米线数组 可见光催化性能 M/TiO2薄膜紫外-可见吸收光谱 

分 类 号：TG146.4[一般工业技术—材料科学与工程]