Persulfate- (PS-) assisted photocatalytic degradation of Methylene Blue (MB) in the hydrothermal synthesis of Ag/Mn3O4 and Ag/Mn3O4/graphene composite catalysts under visible-light irradiation was highlighted in this study. The influence of graphene on the photocatalytic performance was evaluated by comparing the activity on both composites. Based on the results, the photocatalytic performance was enhanced by graphene. Specifically, the optimal photocatalytic activity was observed for Ag-to-Mn3O4 molar ratio of 1 : 0.5 in Ag/Mn3O4 composites, as well as in Ag/Mn3O4/graphene composites with 5 wt.% graphene concentration. Moreover, the results indicated a significant improvement in the photocatalytic performance of both composites with the addition of persulfate (PS) under visible-light irradiation. Accordingly, for PS concentrations of up to 12 mM, the initial MB degradation rate constant increased from 0.0129 to 0.0337 min−1 and from 0.0414 to 0.1627 min−1 in 2 h for Ag/Mn3O4 and Ag/Mn3O4/graphene composites, respectively. Furthermore, the influence of inorganic ions, including Cl−, SO42−, NO3−, H2PO4−, CO3−, K+, Ca2+, and Mg2+, which are usually present in industrial wastewaters, was likewise investigated. The inhibition effect for MB degradation by these ions was in the order H2PO4− > CO32− > SO42− > Cl− > NO3− for the anions and Ca2+ > Mg2+ > K+ for the cations.
|Journal||Environmental Nanotechnology, Monitoring and Management|
|Publication status||Published - May 2021|
- Organic ions
- Photocatalytic degradation