Abstract
The present investigation describes the photocatalytic degradation of methylene blue (MB) and rhodamine-B (RhB) using molybdenum disulfide (MoS2) anchored metal-organic frameworks (MOFs) under visible light irradiation. Herein, MIL-88(Fe) was successfully modified with MoS2 to yield a novel heterogeneous MoS2@MIL88(Fe) hybrid composite. The prepared catalyst enhances the superior photocatalytic activity than the pristine form of MoS2 and MIL-88(Fe) framework. The physico-chemical properties of the prepared catalyst were analytically investigated and the results exhibit greater photocatalytic efficiency towards the chosen dyes, with an optical band gap of 2.75 eV. The MoS2 and MIL-88(Fe) framework could act as efficient oxidation and reduction sites in the as-synthesized MoS2@MIL-88(Fe) composite, and generated the non-toxic by-products such as hydroxyl ((OH)-O-center dot), and superoxide species (O-center dot(2)-) for the mineralization of MB and RhB dyes. The degradation kinetics showed that the dye system followed a pseudo-first-order model which is well supported by the Langmuir-Hinshelwood mechanism. Moreover, the reusability studies showed excellent photocatalytic activity after five cycles. Finally, the photocatalytic degradation mechanism of MB and RhB dyes was suggested.