TiO_2纳米纤维无纺布的制备及光催化性能研究

Fabrication and Photocatalytic Property of TiO_2 Nanofibers

以聚乙烯吡咯烷酮(PVP)作为配位剂与钛酸正丁酯(Ti(C4H9O)4)反应制得前驱体,再以乙醇为溶剂,CH3COOH作为催化剂,采用静电纺丝法制得PVP/TiO2复合纳米纤维,经550℃、700℃和900℃焙烧后分别得到以锐钛矿型的TiO2为主、以金红石型TiO2为主和完全金红石晶型的TiO2纳米纤维。对所制得的纳米纤维的结晶度、纯度和形貌,分别采用差热-热重分析(TG-DTA)、红外光谱(IR)、X射线粉末衍射(XRD)、扫描电镜(SEM)等进行了表征。光降解苯酚水溶液的实验结果表明,550℃下煅烧得到的以锐钛矿占主体的TiO2纳米纤维,2h使浓度为50mg·L-1苯酚水溶液的降解率超过85%,这充分说明这种TiO2电纺纳米纤维具有良好的光催化性能。

PVP/TiO2 composite nanofibers were prepared by Sol-gel processing and electrospinning technique using tetrabutyl titanate and polyvinglpyrrolidone （PVP） as starting materials. Pure TiO2 nanofibers with a diameter of 200 -350 nm were obtained by high temperature calcination of the organic-inorganic composite nanofibers. The materials were characterized by X-ray diffraction （XRD）, thermogravimetry-differential thermal analysis （TG-DTA）, infrared （IR）, and scanning electron microscopy （SEM）. It is observed that both the crystallinity and the morphology of the fibers depend on the calcination temperature. After calcination of PVP/ TiO2 composite nanofibers at 550 ℃, anatase phase TiO2 nanofibers could be obtained. The anatase could be converted into rutile via calcination in air at 700 ℃. The process of the photocatalytic degradation of phenol by using TiO2 nanofibers as catalyst was investigated. The result shows that the TiO2 nanofibers calcined at 550 ℃ have a better photocatalytic property for phenol degradation.