“…This different optical response results in monolayer molybdenum disulde (2D-MoS 2 ) promoting the Raman scattering of incident radiation through charge transfer to the molecule upon irradiation with an estimated Raman enhancement factor of ∼3 × 10 5 which is comparable to values reported for silver and gold. 14,24,25 Techniques of preparing 2D-MoS 2 include chemical vapor deposition, 25,26 sonication, 27 alkali metal exfoliation, 17 and electro-ablation of mechanically deposited bulk MoS 2 . 13 Electrochemical methods can produce thin lms of deposited amorphous MoS x (2 < x < 3) which, aer annealing under a sulfur or argon atmosphere at 500 or 550 °C, attain the desired crystallinity as MoS 2 .…”