Molybdenum Disulfide-Based Photocatalysis:Bulk-to-Single Layer Structure and Related Photomechansim for Environmental Applications

Bulk-to-single layer molybdenum disulfide (MoS2) is widely used as a robust candidate for photodegradation of organic pollutants, hydrogen production, and CO2 reduction. This material features active edge sites and narrow band gap features, which are useful for generating reactive species in aqueous suspensions. However, the high-charge carrier recombination, photocorrosion, unstable sulfide state, and formation of Mo-S-O links during photocatalytic reactions limit its applicability. Thus, research has focused on improving the performance of MoS2 by tailoring its bulk-to-single layer structure and combining it with other semiconductor materials to improve the photocatalytic performance. Different strategies have been successfully applied to enhance the photocatalytic activity of MoS2, including tailoring of the surface morphology, formation of heterojunctions with other semiconductors, doping, and modification with excess sulfur or carbon nanostructures. This review describes the influence of starting precursors, sulfur sources, and synthetic methods to obtain heterostructured morphologies and study their impact on the photocatalytic efficiency. Finally, the relevance of crystal facets and defects in photocatalysis is outlined. Future applications of MoS2 with tailoring and tuning physicochemical properties are highlighted