氟改性TiO2的制备及光催化性能研究

以钛酸丁酯为钛源,氟化铵为氟源,采用溶胶凝胶法制备氟改性二氧化钛光催化剂,并用扫描电镜(SEM)、X射线衍射(XRD)、紫外可见光分度计(UV-Vis)、X射线光电子能谱(XPS)、光致发光荧光光谱仪(PL)、氮气吸附-脱附等方法对样品进行表征。以甲基橙(MO)为模拟污水,研究其光催化活性。结果表明:F改性TiO2为纳米锐钛矿相,比表面积为141m^2/g。F以化学吸附态存在于TiO2的表面,形成≡Ti-F基团,F的加入使得TiO2的吸收带边发生了红移,在甲基橙浓度为20mg/L,紫外光照射时间为80min时,F改性TiO2的脱色率最大达到了97%,具有较高的光催化活性。

Preparation and Photocatalytic Property of F-Modified TiO2

Fluorine doped TiO2(F-TiO2)catalyst was prepared by the sol-gel method using butyl titanate as the titanium source and ammonium fluoride as the fluorine source.The F-TiO2 microspheres were characterized and analyzed by X-ray diffraction(XRD),electron microscope scanning(SEM),rultraviolet and visible spectrophotometer(UV-Vis),N 2 adsorption-desorption,X-ray photoelectron spectroscopy(XPS),photoluminescence spectroscopy(PL).The photocatalytic degradation performance was evaluated under the condition of methyl orange(MO)simulating wastewater.The results show that F-TiO2 microspheres were nanometer anatase,which is formed by fine nanocrystals.The specific surface areas of the sample was 141 m^2/g.F exists on the surface of TiO2 as a chemisorbed state and forms Ti-F bonds.The addition of F makes the absorption band edge of TiO2 red shift.When the methyl orange solution with 20 mg/L of initial mass concentration under UV light using F-TiO2 microspheres for 80 min,the maximum degradation rate reached 97%with high photocatalytic activity.