Multi-layered porous hierarchical TiO_2/g-C_3N_4 hybrid coating for enhanced visible light photocatalysis

摘要

Traditional photocatalysts are difficile to conform the provision of visible light catalysis, conducive recycling and eminent efficiency, which limits their practical applications for decomposing organic pollutants in wastewater. Herein, a multi-layered porous hierarchical titanium dioxide/graphitic carbon nitride (TiO2/g-C3N4) hybrid coating is in-situ generated on titanium (Ti) substrate by sequentially employing plasma electrolytic oxidation (PEO), alkali immersing and hydrothermal reaction. The as-prepared coating exhibits surpassing photocatalytic performance to decay Rhodamine B (RhB) than g-C3N4 and TiO2 photocatalysts under 5 W LED visible light with 240 h cyclic stability. Moreover, the electrons transport and Z-scheme mechanism for TiO2/g-C3N4 heterojunction is pursued to account for the ultralow recombination of photo-induced electron-hole and the enhanced catalytic properties. Not only that, it inhibits the secondary pollution which has further intensified its significance for degradation of organic pollution in sewage treatment systems.