PEG分子量对TiO_(2)微观结构和光催化性能的影响

Microstructure and Photocatalytic Properties of TiO_(2) with Different PEG Molecular Weight

采用溶胶-凝胶法制备了不同分子量的PEG改性的TiO_(2)光催化材料(PEG-TiO_(2))。利用X射线衍射仪和拉曼光谱,表征和分析了PEG-TiO_(2)的微观结构,以亚甲基蓝溶液为降解对象,评价了不同分子量的PEG-TiO_(2)的光催化性能。实验结果表明,制备的PEG-TiO_(2)为锐钛矿和金红石的混合晶体结构,其中,锐钛矿含量与PEG分子量有关,在PEG改性的TiO_(2)样品中,加入的PEG分子量为1500时,TiO_(2)(PEG 1500-TiO_(2))的锐钛矿含量最高。光催化实验结果表明,不同的PEG-TiO_(2)对亚甲基蓝溶液的降解率不同,经紫外光照射50min后,PEG 1500-TiO_(2)对亚甲基蓝溶液的降解率达到86.5%,无PEG的TiO_(2)对亚甲基蓝溶液的降解率为59.8%。

PEG-TiO_(2)photocatalytic materials with different molecular weights of PEG was prepared by Sol-gel method. The microstructure of PEG-TiO_(2)were characterized and analyzed by X ray diffraction(XRD) and Raman spectra. The photocatalytic properties were evaluated by using the methylene blue solution as the degradation objects. The results indicated that PEG-TiO_(2)had a anatase/rutile mixed crystal structure. The content of anatase structure was related to the PEG molecular weight. The PEG1500-TiO_(2)had the highest anatase structure in all the PEG-TiO_(2)samples. The results of photocatalytic experiments showed that the degradation of methylene blue solution varied with PEG molecular weight. After 50min of UV irradiation, The degradation rate of methylene blue solution by PEG 1500-TiO_(2)was 86.5%, compared with 59.8% for TiO_(2)without PEG addition.