CQDs-G-TiO2复合材料制备及光催化性能研究

以钛酸四丁酯为前驱体,石墨烯为辅助修饰剂,丙三醇为碳量子点(CQDs)碳源,一步水热法制备碳量子点修饰复合材料CQDs-G-TiO2,对其进行表征,并研究用于在白光和紫外光源下降解水中亚甲基蓝.结果表明,傅里叶变换红外光谱、热损失、X射线衍射、扫描电子显微镜、能谱显示成功制备了CQDs-G-TiO2复合材料,颗粒较均匀;固体紫外漫反射证明CQDs-G-TiO2增强其在可见光区的光吸收.白光下CQDs-G-TiO2对亚甲基蓝的降解率比纯TiO2降解率提高了38.86个百分点,CQDs-G-TiO2在白光下比在紫外光源下降解率提高了55.71个百分点;CQDs-G-TiO2随溶液pH的增加降解性能增加,白光光源下,pH为9时,CQDs-G-TiO2对亚甲基蓝溶液在70min达到降解平衡,降解率达94.91%.

Study on Preparation of CQDs-G-TiO2 Composites and Its Photocalytic Properties

Carbon quantum dots modified graphene-TiO2 (CQDs-G-TiO2) was prepared by one step hydrothermal synthesis using tetrabutyl titanate as precursor, propanetriol as carbon dots's source and graphene as auxiliary modifier, and the material was characterized and used for methylene blue degradation in water under white and ultraviolet light. The results showed that CQDs-G-TiO2 composites were successfully prepared and particles were uniform through FT IR, teat loss, X ray diffraction, scanning electron microscope and energy spectrum analysis. DRS showed that CQDs-G-TiO2 enhanced their light absorption in visible region, and the degradation rate of methylene blue by CQDs-G-TiO2 was 38.86% higher than that of pure TiO2 composites at white light, the degradation rate of methylene blue by CQDs-G-TiO2 at white light was 55.71% higher than that at ultraviolet light source;the degradation property of CQDs-G-TiO2 increased with the increase of pH of the solution, and the degradation equilibrium of methylene blue solution was achieved at pH 9 under white light source in 70 min, at the same time the degradation rate was 94.91%.