High interfacial charge separation in visible-light active Z- scheme g-CN/MoS heterojunction: Mechanism and degradation of sulfasalazine.

Examination of highly proficient photoactive materials for the degradation of antibiotics from the aqueous solution is the need of the hour. In the present study, a 2D/2D binary junction GCM, formed between graphitic-carbon nitride (g-CN) and molybdenum disulphide (MoS), was synthesized using facile hydrothermal method and its photo-efficacy was tested for the degradation of sulfasalazine (SUL) from aqueous solution under visible-light irradiation. Morphological analysis indicated the nanosheets arrangement of MoS and g-CN. The visible-light driven experiments indicated that 97% antibiotic was degraded by GCM-30% within 90 min which was found to be quite high than pristine g-CN and MoS at solution pH of 6, GCM-30% dose of 20 mg, and SUL concentration of 20 mgL. The degradation performance of GCM-30% was selectively improved due to enhanced visible-light absorption, high charge carrier separation, and high redox ability of the photogenerated charges which was induced by the effective Z-scheme 2D/2D heterojunction formed between g-CN and MoS. The reactive radicals as determined by the scavenging study were •O, and h. A detailed degradation mechanism of SUL by GCM-30% was also predicted based on the detailed examination of the band gaps of g-CN and MoS.