Preparation of g-C3N5/MOF(Ti) for photocatalytic degradation sulfamoylmethylpyrimidine from municipal wastewater

The g-C₃N₅/NH₂-MIL-125(Ti) S-scheme heterojunction is synthesized combined with the advantages of NH₂-MIL-125(Ti) and g-C₃N₅ for photocatalytic degradation sulfamoylmethylpyrimidine (SMT) from wastewater. The construction of the S-type heterojunction of g-C₃N₅/MOF(Ti) effectively promotes the efficient separation of photogenerated carriers and significantly improves the photocatalytic activity. The construction of the S-type heterojunction solves the problems of weak visible light absorption response and photogenerated carrier recombination of photocatalytic materials such as TiO₂, g-C₃N₄ and MOF. The existence of the S-type heterojunction is proved by characterization analysis. The influence of the g-C₃N₅/MOF(Ti) dosage, SMT concentration and solution pH on SMT removal is investigated with a large degradation removal of 97.4 %. The inorganic salt ions and water matrices have slightly influenced SMT removal. The g-C₃N₅/MOF(Ti) still has good reusability after 5 cycles, which is very important in practical applications. However, the natural light is not stable and requires artificial light sources, which will increase energy consumption in practical applications. The g-C₃N₅/MOF(Ti) shows a large mineralization degree for the SMT. The SMT photocatalytic mechanism is analyzed, based on energy band structure data calculations and density functional theory calculations.