Significantly enhanced visible-light photocatalytic activity of g-C3N4 via ZnO modification and the mechanism study
writer：Wei Liu, Mingliang Wang*, Chunxiang Xu, Shifu Chen, Xianliang Fu*
keywords：g-C3N4, ZnO, photocatalytic activity
source：期刊
specific source：J. Mol. Catal. A: Chem. 368-369, 9-15, 2013.
Issue time：2013年
The highly effective ZnO/g-C3N4 photocatalysts with different ZnO amount were prepared by an economic and environmentally friendly method. The photocatalysts were characterized by X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy, UV–vis diffuse reflectance spectroscopy, and Brunauer–Emmett–Teller surface area. The results showed that photocatalytic activity of the photocatalyst was much higher than that of pure g-C3N4 via photodegradation of Rhodamine B under visible light irradiation. The kinetic constant of RhB degradation over ZnO(15 wt.%)/g-C3N4 was 3.1 times that of pure g-C3N4. Effect of ZnO content on the photocatalytic activity of ZnO/g-C3N4 was studied in detail. The active species in RhB degradation were examined by adding a series of scavengers. The study on photocatalytic mechanism revealed that the electrons injected directly from the conduction band of g-C3N4 to that of ZnO, resulting in the production of 
O2? and OH radicals in the conduction band of ZnO. Simultaneously, the rich holes in the valence band of g-C3N4 oxidized Rhodamine B directly to promote the photocatalytic degradation reaction. This work may provide some insight into solving the unsatisfactory catalytic activity and low efficiency converting solar radiation for practical applications of g-C3N4.