Size-Dependent Plasmonic Mode Evolution and SERS Performance of β‑Sn Nanoparticles

Well-crystallized β-Sn nanoparticles with different diameters have been prepared by a wet chemical method at different reaction temperatures. Both optical characterizations and finite element simulations confirmed that higher-order resonance modes will appear when the size of nanoparticles gets bigger and the plasmon resonance absorption peaks resulting from all resonance modes will keep red-shifting with the increase in the size of nanoparticles. In addition, surface-enhanced Raman scattering measurements and corresponding calculations indicate that β-Sn nanoparticles could reveal a near-field enhancement effect and therefore could be an alternative efficient plasmonic material for the Si-based optoelectronic and/or photovoltaic devices.