板式纳米碳纤维负载二氧化钛光催化复合材料的制备及降解甲基橙的研究

以板式纳米碳纤维为载体,采用酸性氧化法对载体进行预处理之后,使用钛酸异丙酯为钛源,高温水热法制备了二氧化钛/纳米碳纤维复合光催化剂,并考察了其对甲基橙的光催化去除能力及循环反应性能.复合材料中二氧化钛含量通过改变前驱体组成进行调节.材料的结构性能通过氮气吸附、X射线衍射(XRD)、能谱分析仪(EDS)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、热重分析仪(TG-DSC)等测试技术进行了表征.结果表明,锐钛矿型的二氧化钛以纳米颗粒形式均匀分散在纳米碳纤维表面,从而形成了高度分散的二氧化钛/碳纤维纳米复合材料.另外,复合系统中中孔吸附作用的存在,与纳米二氧化钛的光催化产生协同作用,增强了复合材料在紫外光照射下对于水溶液中甲基橙的去除能力.在光照射下反应120 min时,不同担载量样品对甲基橙的去除率最高可达80.1%,不同煅烧温度样品最高可达79.2%.此外,光催化剂有着良好重复利用性能,3次循环反应后对甲基橙去除率仍可保持80.0%.

Preparation of TiO2/Platelet Carbon Nanofiber nanocomposites and Their Photocatalytic performance for Degradation of Methyl Orange

Platelet nanofibers (PCNF) pretreated by acidity oxidation treatment was employed as supports to prepare TiO2/PCNF nanocomposites by a hydrothermal process with titanium (IV) isopropoxide as the precursor, its photocatalysis activity and recycle property were investigated. The TiO2 content of photocatalysts was turned by changing the precursor composition. The pure PCNF and the composites were characterized by Nitrogen adsorption, XRD, TG-DSC, SEM and Energy disperse spectroscopy, and TEM. The results showed that anatase TiO2 nanoparticles could be highly dispersed on the surface of fibers, leading to the formation of high performance photocatalysts for degradation of Methyl orange (MO) under UV irradiation. The MC promoted the dispersion of TiO2 in composite system and induced synergistic effects of adsorption and phtocatalytic degradation on the removal of MO. The highest MO remove rate could reach as high as 80.1 % in 120 min for different TiO2 content samples and 79.2 % for different temperature under UV irradiation. After three cycle reaction, the MO remove rate could still reach 80 %.