Application of scanning probe energy loss spectroscopy to SERS-active metal nanostructures

Surface-enhanced Raman spectroscopy (SERS) relies on adsorbing target molecules onto metal nanostructures where the light can resonantly couple with localised surface plasmon resonances. These plasmons can be tuned by changing the nanostructure size, shape, spacing and composition, but this is a complex process. Therefore, having an experimental method that can directly map the plasmons would be extremely useful for developing SERS-active substrates. This paper investigates the possibility of applying a novel scanning probe method, scanning probe energy loss spectroscopy, to map the plasmonic behaviour of SERS-active metal nanostructures in order to optimise their enhancement factor and reproducibility.