以钛酸四丁酯为前驱体,二甲基甲酰胺为N源,HCl为水解控制剂,采用聚合溶胶一凝胶法制备具有可见光响应的TiO2介孔材料。通过X线光电子能谱(XPS)、X线衍射(XRD)、N2等温吸附一脱附测试,考察N在TiO:晶格中的掺杂形式以及HCl加入量对试样的结构性质和可见光催化性能的影响。结果表明:当HCl与钛酸四丁酯的摩尔比值(r)分别为2、3、4时,400℃煅烧后制备得到的材料均为单一锐钛矿晶型,晶粒尺寸控制在10.5-11.5nm;随着r的增大,材料的比表面积、孔隙率及孔径增大,比表面积为19.6~77.8m2/g,孔径为3.7~5.4nm;N掺杂TiO2材料具有良好的可见光催化活性,且对甲基橙的降解能力随着HCl加入量的增大而显著增大;当r为4时,试样对甲基橙的催化降解率最高,1h后达到99.2%。
Visible-light-driven nitrogen-doped titanium dioxide was synthesized by the sol-gel method, with dimethylformamide as nitrogen resource and hydrochloric acid (HCl) as hydrolysis control agents. The do- ping type of N in the crystal lattice of the material was investigated by the X-ray photoelectron spectroscopy (XPS). The influences of HC1 on the microstructure and the photocatalytic characteristics were also ana- lyzed by X-ray diffraction (XRD) and N2 adsorption and desorption. When the molar ratio of HC1 and tita- nium terabutoxide was varied from 2 to 4, the N-doped TiO2 catalysts could be obtained in anatase at 400℃ and the crystal sizes could be controlled in the range of 10. 5-11.5 nm. At the same time, the specific- surface area (19. 6-77.8 m2/g), the pore size (3.7-5.4 nm)and porosity of the material increased with the concentration of HCl increasing. The photocatalytic activities tests were measured by the degradation of methyl orange (MO) in an aqueous solution. Results showed that all the samples had remarkable degradation effect on methyl orange and the degradation effect was increased with the concentration of HCl. When the ratio of HC1 and titanium terabutoxide was 4, the maximum degradation rate was 99. 2% after reaction for 1 h.