Li_(2)SnO_(3)/WO_(3)复合材料的制备用于光催化降解罗丹明B

Preparation of Li_(2)SnO_(3)/WO_(3) composites for photocatalytic degradation of Rhodamine B

采用高温退火法制备了不同质量分数的Li_(2)SnO_(3)/WO_(3)复合物光催化剂,利用X射线衍射(XRD)、扫描电子显微镜(SEM)和紫外-可见分光光度计等对催化剂进行了基本物性表征,采用降解罗丹明B的方法对其进行了光催化活性测试。因复合物中Li_(2)SnO_(3)和WO_(3)能带结构的理想匹配(Type-II型)增强了光生载流子的有效分离,Li_(2)SnO_(3)/WO_(3)复合物光催化剂相比于单体型催化剂具有更高的降解效率。实验结果表明,Li_(2)SnO_(3)/WO_(3)复合物中WO_(3)与Li_(2)SnO_(3)质量比为3%时表现出最优的催化性能,其光催化活性分别是单体Li_(2)SnO_(3)和WO_(3)的2.5倍和8.2倍。

In this work,Li_(2)SnO_(3)/WO_(3) composite photocatalysts with different mass fractions are prepared by heat treatment.The photocatalysts are characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),and ultraviolet-visible spectrophotometer.The photocatalytic activity is tested by degradation of Rhodamine B(RhB).Compared with single phase catalyst,Li_(2)SnO_(3)/WO_(3) heterojunction photocatalyst has higher degradation efficiency because of the excellent band structure matching between Li_(2)SnO_(3) and WO_(3)(Type-II),which enhances the efficient separation of photo-generated carriers.The experimental results show that the optimal performance of Li_(2)SnO_(3)/WO_(3) composite can be obtained when the mass ratio of WO_(3) to Li_(2)SnO_(3) is 3%,which photocatalytic activity is 2.5 times and 8.2 times higher than that of pure Li_(2)SnO_(3) and WO_(3),respectively.