Enhanced photocatalytic performance of protonated graphite carbon nitride/molybdenum sulphide heterojunction for degradation of methyl orange dye

Protonated g-C3N4/MoS2 heterojunction with enhanced photocatalytic activity was prepared by treating g-C3N4/MoS(2)with formic acid and using a hydrothermal method. The microstructure and morphology of the heterojunctions were analysed by XRD, FTIR, SEM, TEM, and XPS technology, respectively. The photodegradation experiment results verified that the formic acid treatment has a positive effect on the photocatalytic performance of g-C3N4/MoS(2)heterojunctions. The as-prepared protonated g-C3N4/MoS(2)composite with 5 wt% of MoS(2)exhibited the highest photodegradation rate and photodegradation kinetic constant (k) for degradation of methyl orange (MO) dye. The activated species trapping experiment revealed that the superoxide radical (center dot O-2(-)) plays an important role for degradation of MO dye. Furthermore, the investigation on the photocatalytic mechanism inferred that the enhanced photocatalytic property of protonated g-C3N4/MoS(2)composite could be attributed to the Z-scheme electron migration mechanism in composite and the improved photo-induced electron-hole separation.

Automated summary

Protonated g-C3N4/MoS2 heterojunction prepared by formic acid treatment and hydrothermal method exhibited enhanced photocatalytic activity, with the highest photodegradation rate and kinetic constant achieved at 5 wt% MoS2 content. Superoxide radical was found to play a crucial role in dye degradation, and the improved photocatalytic performance was attributed to the Z-scheme electron migration mechanism and enhanced photo-induced electron-hole separation in the composite.