CdS-Bi2MoO6/RGO nanocomposites for efficient degradation of ciprofloxacin under visible light

A ternary visible light-driven catalyst, reduced graphene oxide (RGO)-based Bi2MoO6 (BMO), modified with CdS, was synthesized for the degradation of ciprofloxacin through solvothermal method. Neither toxic reductant nor toxic solvent was used. The structural characterization shows that graphene oxide sheets were reduced, while BMO nanoplates and CdS nanoparticles grew to form CdS-BMO/RGO simultaneously. The modification of BMO with CdS and RGO extraordinarily enhances the photocatalytic performance of BMO on the degradation of ciprofloxacin (CIP) under visible light irradiation. The photodegradation rate of CIP over CdS-BMO/RGO photocatalyst is approximately 24 times faster than that of BMO. The improvement of the photocatalytic performance is attributed to the synergistic effect among CdS, BMO and graphene. Moreover, CdS-BMO/RGO exhibits better performance on the degradation of CIP than most bismuth oxide-containing catalysts recently reported. Degradation of various organic contaminants in addition to CIP has also been studied, showing that CdS-BMO/RGO exhibits much higher photocatalytic performance on degrading molecules containing smaller conjugated system.