纳米钛酸锶的结构、光学性质及其光催化还原CO_2性能

Structure and optical properties of nanoscale strontium titanate and its activity of photocatalytic CO_2 reduction

采用水和乙二醇作为热溶剂合成了纳米钛酸锶,以X射线衍射(XRD),扫描电镜(SEM),氮气吸附(BET)等对其结构表征,表明采用乙二醇作为热溶剂得到的块状钛酸锶具有多孔结构,比表面积可达191 m2/g。通过紫外可见漫反射吸收(UV-vis)、荧光光谱(PL)、光电流等方法对样品的光学性质进行测试,程序升温化学吸附仪(TPD)对样品的CO2化学吸附进行测定,在氙灯照射下钛酸锶对CO2进行光催化还原。结果表明,以乙二醇作为热溶剂得到的钛酸锶其光催化还原CO2的效率是以水作为热溶剂得到的钛酸锶的2倍。

Nanoscale strontium titanate was synthesized by hydrothermal methods that using water and ethylene glycol as the thermal solvent respectively. The structure of the samples were characterized by X-ray diffraction（ XRD）,scanning electron microscopy（ SEM） and nitrogen adsorption（ BET）,which indicating that the bulk strontium titanate obtained by using ethylene glycol as the thermal solvent has a porous structure and the surface area reaches to 191 m2/g. The UV-Vis diffusive reflectance spectrophotometer（ UV-Vis）,photoluminescence spectroscopy（ PL） and photocurrent were used to characterize the optical properties of the samples. The adsorption of carbon dioxide was determined by a temperature programmed desorption（ TPD）. The photocatalytic activity of the strontium titanate was evaluated by photo reduction carbon dioxide with a xenon lamp as simulated solar radiation. The results show that the rate of photoreduction of carbon dioxide over strontium titanate obtained by using ethylene glycol as the thermal solvent is two times of strontium titanate obtained by using water as the thermal solvent.