Non-Plasmonic SERS with Silicon: Is It Really Safe? New Insights into the Optothermal Properties of Core/Shell Microbeads

• DOI: 10.1021/acs.jpclett.8b00662
• Publication Date: 2018-03-30T19:32:53Z
• Authors: Nicolò Bontempi; Irene Vassalini; Stefano Danesi; Matteo Ferroni; Maurizio Donarelli; Paolo Colombi; Ivano Alessandri
• Keywords: Nanoshell; Thermal Stability

Silicon is one of the most interesting candidates for plasmon-free surface-enhaced Raman scattering (SERS), because its high-refractive index and thermal stability. However, here we demonstrate that alleged stability silicon nanoshells irradiated by conventional laser cannot be taken granted. We investigated opto-thermal behavior SiO2/Si core/shell microbeads (Si-rex) with three common sources (λ = 532, 633, 785 nm) under real working conditions. obtained an experimental proof critical role played bead size aggregation in heat light management, demonstrating that, case strong coupling, temperature can exceed melting points both core shell components. In addition, also show weakly coupled beads utilized as stable substrates SERS experiments.