Highly efficient visible-light photocatalytic activity of MoS2–TiO2 mixtures hybrid photocatalyst and functional properties

Abstract

2-D-layered molybdenum disulfide (MoS₂) and MoS₂/TiO₂ nanocomposite were synthesized by a hydrothermal method. The effects of the concentration of TiO₂ on the formation of MoS₂/TiO₂ composites and functional properties were investigated. X-ray diffraction patterns revealed the formation of hexagonal and anatase structure of MoS₂ and TiO₂, respectively. Core-level X-ray photoelectron spectroscopy confirmed the presence of Mo and Ti interaction by a significant peak shift. Morphological analysis revealed the formation of TiO₂ on the surface of the MoS₂ nanosheets. The photocatalytic degradation of methylene blue (MB) in an aqueous suspension was employed to evaluate the visible-light activity of the as-prepared composite photocatalyst. The MB absorption peaks completely disappeared after 12 min with 99.33% of degradation under visible-light irradiation at the TiO₂ concentration of 0.005 M. It was found that hydroxyl radical (˙OH) played an important role in the degradation of MB under visible-light irradiation. The possible charge-transfer mechanism has been proposed in this study.