Comparison of the surface-enhanced Raman scattering on sharp and truncated silver nanocubes

Sharp and truncated Ag nanocubes ranging from 60 to 100 nm in size were synthesized, and the surface-enhanced Raman scattering (SERS) activities of these nanoparticles were compared with respect to both size and shape (i.e. sharp vs. truncated) using 514 or 785 nm lasers. Two trends were observed: (i) larger particles (90 and 100 nm) were found to have higher SERS efficiencies, and (ii) particles with shaper corners gave more intense SERS signals than their truncated counterparts. The difference in enhancement factor was mainly attributed to the variation in overlap between the laser source and surface plasmon resonance (SPR) bands as a function of size and degree of truncation.