碱法纳米纤维素模板剂合成介孔TiO_2及其性能

Synthesis and Properties of Mesoporous TiO_2 Using Nano-cellulose Template Prepared by Alkali Method

以生物可再生资源碱法纳米纤维素为模板剂,TiCl4为钛源,采用液相水解-沉淀法合成了具有介孔结构的TiO2光催化剂,采用透射电镜、X射线衍射、热重差热、低温N2物理吸附-脱附等技术对催化剂进行了表征,并以苯酚为模型物,考察了介孔TiO2的光催化活性.结果表明,所得TiO2催化剂具有良好的孔隙结构,平均孔径6.17nm、比表面积176.3m2/g、平均晶粒尺寸13.5nm.碱法纳米纤维素的加入在一定程度上提高了锐钛矿相向金红石相转变的温度.该TiO2晶粒小、孔隙较多、比表面积大、吸附性能强,因此表现出较高的光催化活性.

Mesoporous TiO2 was synthesized by a hydrolysis-precipitation method using biological renewable resources of nano-cellulose as template and using TiCl4 as precursor. The photocatalytic activity of TiO2 was investigated by the degradation of phenol under ultraviolet light irradiation. Transmission electron microscopy, X-ray diffraction, thermogravimetry-differential thermal analysis, and N2 adsorption-desorption were used for catalyst characterization. The results showed that TiO2 synthesized with alkali nano-cellulose template exhibited high activity under UV irradiation. The material had average size of about 13.5 nm in diameter and exhibited mesoporous structure with specific area of 176 m2/g and average pore size of 6.17 nm. The addition of alkali nano-cellulose template can retard phase transformation. The higher photocatalytic activity was attributed to the small grain size, more pores, and higher specific surface area of the catalyst.