氮掺杂TiO2纳米粉体的制备及其可见光催化性能

摘要

N-doped nano-TiO2 (anatase) powders were prepared by calcining titania gel precursor at different temperatures. The gel precursor was obtained by improved sol-gel method using tetrabutyl titanate and urea as source. The samples were characterized and analyzed by XRD, XPS and UV-Vis diffuse reflectance spectroscopy (DRS). The results show that nitrogen element is successfully introduced to titania crystal lattice, and the nitrogen content decreases with the increase in calcination temperature and time. UV-Vis diffuse reflectance spectroscopy (DRS) results indicate that all samples have a red shift, and the absorption band of the sample calcined at 400℃ for an hour shifted up to 700nm. The photodegradation of methylene blue shows that N-doped nano-TiO2 powders have high visible-light photocatalytic properties.%以钦酸四丁酯和尿素为原料,采用溶胶-凝胶法制备了TiO2凝胶前驱体,干燥后在不同温度下进行热处理得到氮掺杂TiO2纳米粉体;以XRD,XPS,UV-Vis DRS等方法对氮掺杂TiO2纳米粉体的晶相、成分和光学性能进行了分析.结果表明,氮元素在TiO2晶格中主要以间隙掺杂形式存在,随着热处理温度升高和时间延长,TiO2粉体中氮的掺杂量逐渐减少.与纯Tio2纳米粉体相比,氮掺杂样品的吸收边均发生明显红移,最大吸收边达到700nm.亚甲基蓝在可见光下的降解实验表明,氮掺杂产物具有良好的可见光催化活性.