N-TiO_2/ZnO复合纳米管阵列的掺杂机理及其光催化活性  

Doping Mechanism of N-TiO_2/ZnO Composite Nanotube Arrays and Their Photocatalytic Activity

作　　者：翟晓辉[1,2] 龙绘锦[1,2] 董江舟[1,2] 曹亚安[1,2] 

机构地区：[1]南开大学物理学院,天津300071 [2]南开大学泰达应用物理学院,天津300457

出　　处：《物理化学学报》2010年第3期663-668,共6页Acta Physico-Chimica Sinica

基　　金：国家自然科学基金(50872056)资助项目~~

摘　　要：以ZnO纳米柱阵列为模板,采用溶胶-凝胶法制备出TiO2/ZnO和N掺杂TiO2/ZnO的复合纳米管阵列.扫描电镜(SEM)、X射线光电子能谱(XPS)和紫外-可见漫反射吸收光谱(UV-Vis)的结果表明:两种阵列的纳米管均为六角形结构,直径约为100nm,壁厚约为20nm;在N-TiO2/ZnO复合纳米管阵列中,掺入的N离子主要是以N-Ox、N-C和N-N的形式化学吸附在纳米管表面,仅有少量的N离子以取代式掺杂的方式占据TiO2晶格O的位置;表面N物种形成的表面态能级和取代式掺杂导致带隙的窄化,增强了纳米管阵列的光吸收效率,促进了光生载流子的分离.光催化实验结果表明,N离子的掺杂有利于N-TiO2/ZnO复合纳米管阵列光催化活性的提高.TiO2/ZnO and N-doped TiO2/ZnO composite nanotube arrays were synthesized by the sol-gel method using ZnO nanorod arrays as a template.Scanning electron microscopy （SEM）,X-ray photoelectron spectroscopy （XPS）,and diffuse reflectance UV-Vis spectroscopy （UV-Vis） were used to characterize the samples.The nanotubes had a uniform hexagonal shape.The diameter and wall thickness of the nanotubes were about 100 nm and 20 nm,respectively.Some N dopants were substitutionally doped into the TiO2 lattice,while the N-Ox,N-C,and N-N were chemically absorbed onto the surface of the TiO2/ZnO composite nanotubes.Dopant-induced narrowing of the bandgap resulted from the doping of N ions into the TiO2 lattices.The surface N species enhanced the visible-light response and promoted the separation of photogenerated carriers.Compared with the TiO2/ZnO composite nanotube arrays,the NTiO2/ZnO composite nanotube arrays exhibited higher photocatalytic activity.

关 键 词：光催化 TiO2/ZnO复合纳米管阵列 N掺杂 掺杂机理 

分 类 号：TB383.1[一般工业技术—材料科学与工程]