碳纳米管负载纳米TiO_2复合材料的制备及其性能

Preparation and Properties of Carbon Nanotube-TiO_2 Nanocomposites

采用溶胶-凝胶法,以钛酸丁酯为原料,将纳米TiO2负载在碳纳米管(CNTs)表面,制备了CNT-TiO2光催化复合材料.通过X射线衍射(XRD)、透射电子显微镜(TEM)等手段研究了复合颗粒的形态结构及包覆情况,通过UV-Vis漫反射谱分析比较了纯TiO2和CNT-TiO2的吸光性能,并研究了不同温度热处理的CNT-TiO2光催化剂在紫外光照射下对甲基橙光催化降解的性能.结果表明,纳米TiO2颗粒以锐钛矿相存在,紧密地包附在碳纳米管的管壁上,CNT-TiO2在紫外-可见光波长范围内均有较好的吸光性能,450℃热处理后的复合光催化剂CNT-TiO2比纯TiO2对甲基橙光降解有更高的光催化活性.

Coating carbon nanotube surface with TiO2 as anatase was performed by sol-gel method using Ti（OBu）4. The morphological structure of the photocatalyst particles was characterized by XRD and TEM. Absorbency was analyzed by the UV-Vis diffuse reflection spectra of TiO2 and CNT-TiO2 photocatalysts. The photocatalytic activities of the materials heat-treated at different reaction temperatures have been tested on decomposable substrate methyl orange solution under UV-light illumination. The results showed that the nanocomposites had excellent photocatalytic ability. When the wavelength was between 200-800 nm, CNT-TiO2 nanocomposites had good absorbency. TEM micrographs showed that TiO2 was closely coated on the surface of carbon nanotubes. The best heat treatment temperature of CNT-TiO2 nanocomposites was 450 ℃ The crystal form of TiO2 was anatase and the diameter of crystal was 7.3 nm. The photodegradation rate of CNT-TiO2 nanocomposites was better than that of pure TiO2 under sunlight.