疏水性空心SiO_2/TiO_2光催化剂的制备及性能研究  

Study on Synthesis of Hydrophobic SiO_2/TiO_2 with Core-Shell Structure and Its Performance

作　　者：刘秀宇[1] 解博[1] 曾祥朋 王双飞[1] 陈国宁[1] 

机构地区：[1]广西大学轻工与食品工程学院,南宁530004

出　　处：《材料导报》2016年第2期13-17,共5页Materials Reports

基　　金：2013年度广西高校科学技术研究项目(2013YB020)

摘　　要：选取TiO_2为原料,经过空心化、SiO_2包覆、疏水性改性,制备了疏水性空心SiO_2/TiO_2光催化剂,并利用TEM和FTIR对其进行表征,对比研究了改性前后的催化剂。TEM图像显示制备的催化剂具有核-壳空心结构,且其表面均匀包覆一层物质;FTIR图谱分析可知,其表面包覆层是SiO_2,且硅烷偶联剂KH-570与其成功产生化学键合;吸附实验时改性光催化剂漂浮在废水表面,提高了光照效率。以甲基橙模拟染料废水的降解率考察改性光催化剂的活性,初始甲基橙浓度为10mg/L、pH值为4时,对甲基橙的脱色率最佳,并且Langmuir和Freundlich等温模型均能较好地描述吸附过程。经动力学的一次拟合,说明该吸附是一个以化学吸附为主导作用的多因素控制过程。Using titanium dioxide as raw material, SiO2/TiO2 catalyst with good hydrophobicity and core-shell structure was prepared through a hollowing-SiO2 coating-hydrophobic modification process and characterized by trans- mission electron microscope （TEM） and Fourier transform infrared spectroscope （FTIR）. TEM showed that the pre- pared catalyst had a core-shell structure with a uniform outlayer coating. FTIR analysis indicated that the coating material was SiO2, which chemically bonded with silane coupling agent KH-570. The absorption experiment showed that the prepared catalyst floated on the surface of waste water during the absorption process, which would further improve the lighting efficiency. The photocatalytic activity of the preparedcatalyst was evaluated based on the photodegradation of methyl orange. The results showed that the decolorization rate of MO reached maximum when the initial solution concentration of MO was 10 mg/L and the initial pH value was 4. Furthermore, the absorption process conformed with Langmuir and Freundlich models properly. First-order fitting of kinetics indicated that the absorption is a multi- factor controlled process, which was dominated by chemical adsorption.

关 键 词：疏水性空心Si02/Ti02光催化剂光催化降解 甲基橙 

分 类 号：X522[环境科学与工程—环境工程] X131.2