N掺杂P25可见光响应型光催化剂的制备及性能

Preparation and property of N-doped visible light response P25 photocatalysts

以P25为改性对象,尿素为N源,采用研磨-煅烧法制备了具有可见光活性的N掺杂改性P25材料(NP25)。采用XPS电子能谱、X衍射、紫外-可见吸收光谱和透射电镜对催化剂的结构进行表征,并考察了N-P25材料在可见光催化下对亚甲基蓝的降解性能。结果表明,XPS检测发现N-P25在399eV处出现一个N1s峰,N1元素的百分比为0.39%,表明N是通过填隙式的掺杂进入P25,以Ti-O-N键存在,改变了P25的能级结构,诱导其发生红移,在可见光下产生光催化活性。光催化降解试验表明,当煅烧温度为400℃时制备的样品在可见光下反应3h对亚甲基蓝的降解率达到最大值,为60.59%。

N-doped P25 photocatalysts with the property of visible light response were prepared used the urea for N sourse and P25 for the raw materials by the method of grinding and calcining. The photocatalysts＇ structure was character ized by XPS, XRD, UV-Vis and TEM. The photocatalytic activity of N-doped P25 was measured by photocatalytic degrada- tion of methylene blue. The results suggested that XPS spectrogram reflected that Nls peak appeared in the point of 399eV, the percentage of N1 element was 0. 39%, so we concluded N was doped into P25 though interstitial way. Doping of N formed Ti-O-N bond, resulted a new band gap to extend the adsorption edge to visible light, which made N-P25 photocat alytic activity under visible light irradiation. Study of photocatalytic degradation indicated that the samples prepared at the calcination temperature of 400℃ were used to degrade methylene blue, after 3h, the degradation reached up to the 60. 59%.