The bandgap can be tuned by introducing strain into the structure. A 300 meV increase in bandgap per 1% biaxial compressive strain applied to trilayer MoS2 has been observed. A vertical electric field has also been suggested to reduce the bandgap in 2D TMDCs – potentially to zero, thereby switching the structure from semiconducting to metallic. Photoluminescence spectra of MoS2 monolayers show two excitonic peaks: one at ~1.92eV (the A exciton) and the other at ~2.08eV (the B exciton). Due to spin-orbit coupling, these are attributed to the valence band splitting at the K-point (in the Brillouin zone), allowing for two optically active transitions. The binding energy of the excitons is >500meV. Hence, they are stable up to high temperatures. Injecting excess electrons into MoS2 (by either electrical or chemical doping) can cause the formation of trions (charged excitons), which consist of two electrons and one hole. They appear as peaks in the absorption and PL spectra, red-shifted by ~40meV concerning the A exciton peak (tunable through doping concentration). While the binding energy of trials is much lower than that of the excitons (at approximately 20meV), they have a non-negligible contribution to the optical properties of MoS2 films at room temperature. MoS2 monolayer transistors generally display n-type behavior, with carrier mobilities approximately 350cm2V-1s-1 (or ~500 times lower than graphene). However, when fabricated into field-effect transistors, they can display massive on/off ratios of 108, making them attractive for high-efficiency switching and logic circuits. If you are looking for high quality, high purity, and cost-effective Molybdenum disulfide, or if you require the latest price of Molybdenum disulfide, please feel free to email contact mis-asia.