氮掺杂TiO_2的制备及其光催化性能研究

应用溶胶-凝胶法,以尿素和钛酸丁酯为原料制备前躯体,前躯体在500℃、焙烧3 h条件下制备不同浓度掺杂氮的TiO2纳米粉体。采用X射线衍射(XRD)、扫描电镜(SEM)、能谱分析(EDS)、紫外可见光谱(UV-Vis)等分析手段对样品的物相、形貌、成分和吸光性能进行表征,并且以亚甲基蓝溶液为模拟污染物在阳光下进行光催化实验。结果表明:样品主要为锐钛矿相二氧化钛及少量的金红石型二氧化钛,颗粒粒径小于300 nm,有一定程度的团聚,样品中含有质量分数分别为0、2.99%、6.23%、11.38%的氮元素,氮掺杂样品的光谱吸收边缘红移至400~470 nm。光催化实验表明:氮掺杂可以大大改善TiO2在可见光波段的光催化性能。

Study on Preparation and Photocatalytic Properties of Nitrogen-doped TiO2

Using urea and tetrabutyl-titanate as raw materials,the precursors were prepared by sol-gel methods,then they were calcined for 3 h at the temperature of 500 ℃.The TiO2 nano-particles with different nitrogen doping concentrations were obtained.The phase,morphology,composition and spectral absorption properties of the powder were characterized and analyzed by XRD,SEM,EDS,UV-Vis etc.And the photocatalytic experiments carried out under sunlight with methylene-blue solution as simulate pollutant.The results showed that the samples were mainly anatase titanium dioxide with a small amount of rutile-type titanium dioxide.The particle sizes were less than 300 nm.The mass fractions of N in samples were 0,2.99%,6.23% and 11.38%.The absorption spectra of nitrogen-doped samples shifted to 400~500 nm.The photo-catalytic experimental results showed that nitrogen doping greatly improved the catalytic properties of TiO2 under sunlight.