Chemically and mechanically exfoliated MoS2 for electronic opto-electronic devices

摘要

Two-dimensional (2D) layered nanomaterials such as graphene and transition-metal dichalcogenides (TMDCs) have attracted tremendous attention over recent years due to their unique properties and potential for numerous applications. Here we have characterized the properties of chemically exfoliated 2D molybdenum disulphide (MoS2) that was dispersed in organic solvents. Optical absorption spectra of the solution dispersions revealed the presence of excitonic peaks at characteristic energies. Besides electronic transport measurements on drop-cast samples, these dispersions were also used to form p-n junction devices on p-type Si substrates. At the same time, MoS2 was also mechanically exfoliated from the bulk crystal and the flake was then placed onto pre-patterned electrodes using a visco-elastic stamping process. A few layer MoS2 photodetector device was fabricated and characterized using a broadband white light source and transport was measured over a wide range of temperatures.