Thin Film of Molybdenum Disulphide, an Emerging Class of Semiconducting Materials: Properties, Characterization and Photovoltaic Applications

Several scholars and scientists have recently continued their efforts to fabricate and develop advanced nanomaterials in the form of nanoparticles, clusters, emulsions, and thin films to design nanoscopic optoelectronic devices, supercapacitors, solar systems, and biomedical equipment. Because of the widespread exceptional physiochemical characteristics and improved functionalities, hybrid nanostructures, including organic and inorganic metaloxides, sulphides and polymeric nanostructures are highly appreciated and explored for enhanced physicochemical, biological, and environmental applications. Therefore, metalsulphides nanomaterials such as CdS, ZnS, MoS2, and PbS, as nano-thin films were widely designed, and employed in various geometries such as 1D, 2D, and 3D nano-thin films, which possess extraordinary functionality. Among them, MoS2 (molybdenum disulfide) is considered as an emerging class of semiconducting material due to its direct bandgap value i.e. (~1.9 eV), has high current on/off ratio (108 ) at normal temperature, and exhibited mobility 200 cm2 Vs−1 . It has the ability to change its architecture from bulk to nanoscale level. On the basis of its unique structure, MoS2 has two characteristics: (i) it possesses a hexagonal structure with SMo-S layers arrangement by covalent bond, and (ii) Van der Waals force of interaction that lies between the adjacent layers of MoS2, which makes it suitable for multiple applications. Moreover, the structural, surface, and optical properties of MoS2 are altered by the stoichiometric doping of metal/ions, which favour its electronic features toward improved work functionalities. This chapter will provide a systematic explanation for the synthesis, design, morphological investigations, and developments of the MoS2 semiconducting nano-thin films for multiple optoelectronic, biochemical, and environmental uses. 

Keywords: 2D nano-thin films, MoS2, Modified structures and surfaces, Solar cells, Sensor applications.