Ultrathin two-dimensional transition metal dichalcogenides represent a promising new class of materials with surface-enhanced Raman scattering (SERS) activities. Previous work mainly focused on the SERS effects of transition metal dichalcogenide crystals with sizes of micrometer scale. The enhancement effect is usually nonuniform on the SERS substrates. In this paper, we report a chemical vapor deposition method for the preparation of centimeter-scale MoSe2 films with uniform and high SERS activity. The molybdenum precursors are supplied in a “face-to-face” manner from a silica gel plate to the growth substrate, which guarantees uniform nucleation and growth of the monolayer MoSe2. We demonstrate that the monolayer MoSe2 film has strong SERS effect, which can be attributed to charge transfer between MoSe2 and the probe molecules. The detection limit of Rhodamine B on monolayer MoSe2 is determined to be 10[Formula: see text][Formula: see text]mol/L, and the Raman enhancement factor is estimated to be [Formula: see text]. Due to its atomic uniformity and chemical stability, the MoSe2 film can serve as an ideal two-dimensional SERS material for detection of various molecules.
Surface-Enhanced Raman Scattering Sensing of Transition Metal Ions in Waters
