Preparation of ZnO/g-C3N4 composite photocatalyst and photocatalytic reduction of U(Ⅵ)
Ming LEI1, Yuelin LIU2,3, Shuibo XIE1,2,*(), Yujie GE1, Yingjiu LIU1
1 School of Civil Engineering, University of South China, Hengyang 421001, Hunan, China 2 Hunan Provincial Key Laboratory of Pollution Control and Resources Technology, University of South China, Hengyang 421001, Hunan, China 3 School of Civil Engineering, Hunan University of Technology, Zhuzhou 412007, Hunan, China
Based on ZnO and melamine, the ZnO/g-C3N4 for photocatalytic U(Ⅵ) reduction was pre-pared by thermal polymerization methods. The surface morphology, lattice structure, element composition and photocatalytic efficiency were analyzed by SEM, XRD, XPS, PL and UV-Vis methods.The results show that the doping of ZnO reduces the recombination rate of photogenerated electrons and holes, expands the response range of the material to visible light, makes ZnO/g-C3N4 have higher photocatalytic activity. When pH=5 and dosage is 0.5 g/L, the highest U(Ⅵ) removal rate can reach 97% after dark reaction for 30 min and light reaction for 30 min. The U(Ⅵ) on the surface of the photocatalyst can be reduced to U(Ⅳ). The photoelectron e- is the main factor for reducing U(Ⅵ) to U(Ⅳ).
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