白云母/TiO_(2)复合材料的制备及光催化性能

Preparation and photocatalytic performance of muscovite/TiO_(2) composites

以钛酸丁酯为钛源、冰醋酸为抑制剂,通过水热法合成白云母/TiO_(2)(M/T)复合光催化材料。采用X射线衍射(XRD),拉曼光谱(Raman),扫描电子显微镜(SEM),能谱仪(EDS),N2吸附-脱附(BET),紫外-可见漫反射光谱(UV-Vis),荧光光谱(PL)对样品的物相结构、表面形貌、元素分布、孔隙结构及光学特性进行表征,并以甲基橙(MO)溶液为目标污染物,考察水热温度、水热时间、TiO_(2)负载量对M/T复合材料光催化性能的影响。结果表明:100℃水热16 h, TiO_(2)负载量为20%(质量分数)的M/T复合材料光催化性能最好;紫外光照射60 min,对MO的降解率达到99.62%,总有机碳(TOC)去除率为63.58%,重复使用5次,光催化活性没有明显降低,且M/T复合材料光降解MO过程符合一级反应动力学模型,最大反应速率常数kapp为0.049 min^(-1)。

Muscovite/TiO_(2)(M/T)composite photocatalytic materials were synthesized by a hydrothermal method using tetrabutyl titanate as the titanium source and glacial acetic acid as the inhibitor.The phase structure,surface morphology,element distribution and optical property of the obtained samples were characterized by X-ray diffraction(XRD),Raman spectra(Raman),scanning electron microscope(SEM),energy disperse spectroscopy(EDS),Brunner-Emmet-Teller(BET),ultraviolet-visible diffuse reflectance spectroscopy(UV-Vis)and fluorescence spectra(PL),respectively.And methyl orange(MO)solution was used as the target pollutant to investigate the effects of hydrothermal temperatures,hydrothermal time and the mass of TiO_(2) on the photocatalytic performance of M/T composites.The results show that the M/T composite with TiO_(2) loading amount 20%(mass fraction)and 100℃hydrothermal for 16 h exhibits the optimal photocatalytic properties,the degradation rate of MO reaches 99.62%and TOC removal rate is 63.58%after UV light irradiation for 60 min.After repeated use for 5 times,the photocatalytic activity is not decreased significantly.Furthermore,the photocatalytic process of M/T composites conforms to the first-order reaction kinetic model and the best reaction rate constant is 0.049 min^(-1).