Dielectrics represent a new frontier for Surface Enhanced Raman Scattering. They can serve either as a complement or an alternative to conventional, metal-based SERS, offering key advantages in terms of low invasiveness, reproducibility, versatility and recyclability. In comparison to metals, dielectric systems and, in particular, semiconductors, are characterized by a much greater variety of parameters and properties that can be tailored to achieve enhanced Raman scattering or related effects. Light trapping and sub-wavelength focusing capabilities, morphology-dependent resonances, control of band gap and stoichiometry, size-dependent plasmons and excitons, charge transfer between semiconductors and molecules and vice-versa are a few examples of the manifold opportunities associated to use of semiconductors as SERS-active materials.
In this talk a few examples  of all-dielectric core/shell colloids for plasmon-free SERS, including applications in biochemistry [3-5] and environmental science, will be presented and discussed, with a special focus on the latest results regarding SERS/mass spectrometry multimodal sensing.
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