半纤维素/TiO_2复合凝胶的光催化降解性能

Photocatalytic degradation property of hemicellulose/TiO_2 composite gel

以半纤维素和TiO_2纳米粒子为原料制得半纤维素/TiO_2复合凝胶。分别用红外光谱分析和扫描电镜对复合水凝胶进行了表征,分析表明半纤维素上成功接枝聚丙烯酸,凝胶呈现多孔结构,且随着TiO_2含量的增加凝胶孔径减小。考察了半纤维素/TiO_2复合凝胶的溶胀性能以及对亚甲基蓝的光催化降解性能,研究表明半纤维素/TiO_2复合凝胶的溶胀率随着TiO_2粒子含量的增加而减小,随着p H的增大先增大后减小;对亚甲基蓝染料的降解率随着TiO_2含量的增加先增大后减小,随着p H的增大先增大后减小,随着亚甲基蓝初始浓度的增大而增大。

Hemicellulose/TiO2 composite gel was prepared using hemicellulose and TiO2 nanoparticles. Fourier transform infrared spectroscopy（FT-IR） and scanning electron microscopy（SEM） were used to study the structure and morphology of the hydrogel. Experimental analysis showed that the hemicellulose was successfully grafted with the polyacrylic acid and a porous hydrogel was observed. The pore size of the hydrogel decreased with the increase of the TiO2 content. In addition, the swelling properties and photocatalytic degradation properties of the hydrogel were also investigated. Experimental results showed that the swelling ratio of the hydrogel increased at first and then decreased with the increase of p H while kept decreasing with the increase of the TiO2 content. The degradation ratio of methylene blue increased at first and then decreased with the increase of the TiO2 content or a rise of p H value of the methylene blue solution, and it also increased with the increase of the initial concentration of methylene blue solution.