Graphene-Like Molybdenum Disulfide and Its Application in Optoelectronic Devices

Graphene-like molybdenum disulfide (MoS2), which is composed of a monolayer or few layers of MoS2, is a new two-dimensional (2D) layered material that has attracted considerable attention recently because of its unique structure and optical and electronic properties. Here we first review the methods used to synthesize graphene-like MoS2. "Top-down" methods include micromechanical exfoliation, lithium-based intercalation and liquid exfoliation, while the "bottom-up" approaches covered are thermal decomposition and hydrothermal synthesis. We then discuss several methods used to characterize the 2D layered structures of MoS2, such as atomic force microscopy (AFM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Raman spectroscopy. We describe the UV-Vis absorption and photoluminescent properties of graphene-like MoS2 and their related mechanisms. Finally, we summarize the application of graphene- like MoS2 in various optoelectronic devices such as secondary batteries, field-effect transistors, sensors, organic light-emitting diodes, and memory. The application principles and research progress are discussed, followed by a summary and outlook for the research of this emerging 2D layered nanomaterial.