Strategy for enhanced photocatalytic activity of amorphous MoS2 as an efficient Photocatalyst for dye degradation: A study on RhB, KMnO4, and mixed dye system

Abstract

In the present work, solvothermal synthesis technique was adopted to synthesize the molybdenum disulfide (MoS₂) nanoparticles. The X-ray diffraction (XRD) analysis reveals the amorphous nature and confirms the poor crystallinity of the as-synthesized MoS₂ nanoparticles. The photocatalytic activity of amorphous MoS₂ was assessed using Rhodamine B (RhB) as a model organic pollutant when exposed to visible light. In addition to RhB degradation, composite systems comprising RhB and KMnO₄, as well as a binary mixture of Methylene Blue (MB), RhB, and KMnO₄, were used to study the synergistic effects of oxidising agents. As a result, MoS₂ catalyst achieved excellent degradation of 93.05% under visible light with addition of KMnO₄ within 60 minutes. In mixed dye degradation analysis, MB degraded to 99.18% and RhB degraded to 85.05% within 8 minutes. Notably, the amorphous MoS₂ exhibit significantly enhanced photocatalytic performance, while KMnO₄ acting as a co-oxidant to improve the degradation efficiency. These results demonstrate that the synthesized amorphous MoS₂ is an efficient visible-light-driven photocatalyst and a promising candidate for advanced oxidation processes (AOPs) aimed at the degradation of complex organic pollutants and multi-dye wastewater systems. Further, the photocatalytic dye degradation of binary mixture of Rhodamine B (RhB) and Methylene blue (MB) dyes was witnessed within a short time frame of 8 minutes, showcasing the rapid and highly efficient photocatalytic activity of the catalyst.