Plasmon Enhancement of Raman Scattering by Mercury Sulfide Microcrystals

Surface-enhanced Raman scattering was demonstrated for mercury sulfide microcrystals on Au-coated Si/Genanostructures, the surfaces of which were composed of three-dimensional arrays of pyramidal shapes, and on gelfilms of globular Ag nanoparticles. In both instances, selective enhancement of bands corresponding to symmetric A1 (256 cm–1) and transverse E(TO) (284 and 344 cm–1) vibrations and appearance of second-order bands were observed. Separate bands in the Raman spectra were enhanced by 14–16 times. The estimated gain factor was ~ (7.9–9.4)·105 taking into account the size of the mercury sulfide microcrystals (~2 μm).