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以钛酸丁酯为钛源,尿素为氮源,聚丙烯酰胺(PAM)和聚乙二醇(PEG)为复合模板剂,采用溶胶-凝胶法,在氮气和空气气氛中分段煅烧,制得高结晶度氮掺杂介孔TiO2光催化剂.利用X射线衍射、透射电镜、N2吸附-脱附、X射线光电子能谱和紫外-可见漫反射光谱等技术对其进行了表征.结果表明,当PAM和PEG的质量比为1:4时,先在氮气中600°C煅烧,后在空气中500°C煅烧所得样品是锐钛矿相,具有良好的孔隙结构和较高的结晶度,平均孔径为5.11nm,晶粒尺寸为12.5nm,比表面积110.8m2/g.掺杂介孔TiO2的氮主要以取代氮和化学吸附分子γ-N2的形式存在,少量以间隙氮形式存在.氮掺杂使TiO2的能带变窄,吸收带边明显红移,且使光吸收强度显著增大.光催化降解甲基橙实验结果表明,与未掺杂样品相比,氮掺杂介孔TiO2在可见光作用下表现出较高的催化活性.
Using butyl titanate as the titanium source, urea as the nitrogen source, polyacrylamide (PAM) and polyethylene glycol (PEG) as the composite templating agent, sol-gel method was used and calcined in nitrogen atmosphere and air atmosphere. The high crystallinity nitrogen-doped mesoporous TiO2 photocatalyst was prepared and characterized by X-ray diffraction, transmission electron microscopy, N2 adsorption-desorption, X-ray photoelectron spectroscopy and UV-Vis diffuse reflectance spectroscopy. , When PAM and PEG mass ratio of 1: 4, first calcined at 600 ° C in nitrogen, calcined at 500 ° C in air after the resulting sample is anatase phase, has a good pore structure and high crystallinity , The average pore diameter of 5.11nm, the grain size of 12.5nm, the specific surface area of 110.8m2 / g.Doping mesoporous TiO2 nitrogen mainly in the form of substituted nitrogen and chemisorption molecule γ-N2, a small amount of interstitial nitrogen exists. Nitrogen doping can narrow the energy band of TiO2, red shift of the absorption band edge obviously and increase the light absorption intensity significantly.Experimental results of photocatalytic degradation of methyl orange show that compared with the undoped sample, the nitrogen doped mesopores TiO2 shows higher catalytic activity under visible light.