Surface-enhanced Raman scattering of monolayer transition metal dichalcogenides on Ag nanorod arrays

In this work, we studied surface-enhanced Raman scattering (SERS) of MS₂ (M=Mo, W) monolayers that were transferred onto Ag nanorod arrays. Compared to the suspended monolayers, the Raman intensity of monolayers on an Ag nanorod substrate was strongly enhanced for both in-plane and out-of-plane vibration modes: up to 8 (5) for E_2g and 20 (23) for A_1g in MoS₂ (WS₂). This finding reveals a promising SERS substrate for achieving uniform and strong enhancement for two-dimensional materials in the applications of optical detecting and sensing.