Preparation of (La-Ce)-codoped ZnO and its photocatalytic activity for degradation of methylene blue

ZnO,La3+/ZnO,Ce3+/ZnO and La3+-Ce3+/ZnO photocatalysts were prepared by a sol-gel process and characterized by X-ray diffraction,transmission electron microscopy,ultraviolet and visible spectrophotometry,and BET specific surface area analysis.The photocatalytic activity of these photocatalysts was investigated by photodegradation of methylene blue(MB).The prepared La3+-Ce3+/ZnO photocatalyst is rectangular column shapes,with the average size of 57.3 nm.La-Ce codoping can increase the crystallinity of ZnO,promote the grain growth of ZnO,and improve the photocatalytic activity of ZnO greatly.In the photocatalytic degradation of 500 mL of 10 mg.L 1 MB,the photocatalytic degradation rate of MB with La3+-Ce3+/ZnO as a photocatalyst is 93.7%,which is 21.4%,19.2%,9.3% higher than those with pure ZnO,La3+-ZnO,Ce3+-ZnO as photocatalysts,respectively.