Preparation And Photocatalytic Properties Of G-C₃N₄-based Composites

In recent years,energy and environment has become one of the hot topics of scientific research,especially the photocatalytic technology.It has own scholars'attention due to its environmentfriendly,clean and renewable use.As an typical non-metal semiconductor material,Graphite phase nitride carbon?g-C₃N₄?has been paid more attention because of its visible-light response,strong carrier transmission capacity,easy preparation method and high stability.However,single g-C₃N₄ has comparatively lower absorption spectrum and higher photogenerated electron-hole recombination efficiency.The disadvantages have seriously restricted its wide application in the field of photocatalysis.This paper was based on the modification of g-C₃N₄.the porous g-C₃N₄ was prepared to increase its specific surface area.Then Coupling g-C₃N₄ with Ag,ZnO and GO to form heterojunctions to improve the utilization efficiency to visible light and prolong the life of the photo-generated carriers.The adsorption efficiency of target pollutant was also enhanced by modified nanocomposites.The main research contents and conclusions are as follows:1.The hydrothermal method and high temperature thermal decomposition method were used to prepare ZnO and g-C₃N₄,respectively.Their structure were characterized by some related methods.Then,the ZnO/g-C₃N₄ nanocomposites were successfully prepared by hydrothermal method.Methylene blue?MB?was set as the target pollutant to explore the photocatalytic activity.2.Ag/ZnO/g-C₃N₄ composites were prepared by photo-reduction method.These prepared composites were characterized by X-ray diffraction?XRD?,X-ray photoelectronspectroscopy?XPS?,scanningelectronmicroscopy?SEM?,transmission electron microscopy?TEM?,ultraviolet-visible?UV-Vis?diffuse reflectance spectroscopy?DRS?and photoluminescence spectra?PL?.Methylene blue?MB?was also set as the target pollutant to explore the photocatalytic activity of ternary composite material.Besides,the stability and regeneration properties of the prepared materials wereinvestigated and the photocatalytic mechanism was also revealed.3.Ag/GO/g-C₃N₄ composites were also synthesized by photo-reduction method and the structure were characterized by some related methods.The effects of different Ag nanoparticles content on the MB degradation efficiency was investigated.