Decoration of mesoporous Co 3 O 4 nanospheres assembled by monocrystal nanodots on g-C 3 N 4 to construct Z-scheme system for improving photocatalytic performance

Abstract The Co 3 O 4 /g-C 3 N 4 Z-scheme system is constructed by decoration of mesoporous Co 3 O 4 nanospheres assembled by monocrystal nanodots on the surface of g-C 3 N 4 , which dramatically improves the photocatalytic activity for degrading tetracycline hydrochloride (TC) compared with single g-C 3 N 4 . The microstructure investigations evidence the mesoporous structure and enlarged specific surface area of Co 3 O 4 /g-C 3 N 4 Z-scheme system, which implies the increase of surface active sites and adsorption ability for reactant molecules. Moreover, by virtue of analyzing physical and photoelectrochemical properties, it evidences that the decoration effect of mesoporous Co 3 O 4 nanospheres on the surface of g-C 3 N 4 obviously improves the transfer and separation efficiency of charge carriers between two phase interfaces and broadens light harvest range. These important factors are beneficial to enhancing photocatalytic activity of Co 3 O 4 /g-C 3 N 4 Z-scheme system. In addition, the photocatalityc reaction mechanism is also revealed in depth.