中文摘要：

采用溶胶-凝胶法在聚乙烯毗咯烷酮（PVP）修饰的碳纳米管表面均匀沉积纳米级二氧化钛粒子制得复合光催化剂。采用透射电子显微镜（TEM）、X射线衍射仪（XRD）、紫外-可见吸收光谱仪（UV-Vis）和X射线光电子能谱仪（XPS）等手段对复合光催化剂进行表征。结果表明，二氧化钛粒子是呈球形、团聚，随机沉积在未修饰碳纳米管任意表面，甚至部分碳纳米管表面是完全裸露的。经PVP修饰后的碳纳米管，二氧化钛纳米粒子均匀沉积在碳纳米管表面，二氧化钛为纯锐钛矿晶体结构，没有金红石和板钛矿相。表面修饰碳纳米管／二氧化钛复合光催化剂在紫外光照射下降解亚甲基蓝，相比纯的二氧化钛和碳纳米管／二氧化钛复合光催化剂，具有非常高的催化活性。

英文摘要：

A novel kind of carbon nanotubes/titanium dioxide （CNTs/TiO2） composite photocatalyst was prepared by a modified sol-gel method in which the nanosealed TiO2 particles were uniformly deposited on the CNTs modified with poly（vinyl pyrroli- done） （PVP）. The composites were characterized by a range of analytical techniques including high resolution transmission elec- tron microscopy （TEM）, X-ray diffraction （XRD）, and X-ray photoelectron spectroscopy （XPS）. The results show the success- ful covering of the CNTs with PVP, forming core-shell structure. The nanoscaled TiO2 particles were uniformly deposited on the surface of CNTs reducing the bare CNTs which avoid losing the absorption and scattering of photons. The combination of CNTs and TiO2 particles imply the enhanced interactions between the CNTs and TiOz interface which possibly becomes heterojunetion. The composites become mesoporous crystalline TiO2 （anatase） clusters after annealing at 500℃, and the surface area increases obviously. The photoeatalytie activities of surface modification CNTs/TiO2 （smCNTs/TiO2） composites are extremely enhanced from the results of the photodegradation of methylene blue （MB）.