Robust raspberry-like metallo-dielectric nanoclusters of critical sizes as SERS substrates. Issue 17 (20th April 2017)

• Record Type: Journal Article
• Authors: Le Beulze, A.; Gomez-Graña, S.; Gehan, H.; Mornet, S.; Ravaine, S.; Correa-Duarte, M.; Guerrini, L.; Alvarez-Puebla, R. A.; Duguet, E.; Pertreux, E.; Crut, A.; Maioli, P.; Vallée, F.; Del Fatti, N.; Ersen, O.; Treguer-Delapierre, M.
• Is Part Of: Nanoscale. Volume 9:Issue 17(2017)
• Page Start: 5725
• Page End: 5736
• Publication Date: 2017-04-20
• Subjects: Nanoscience -- Periodicals; Nanotechnology -- Periodicals; 620.505
• DOI: 10.1039/c7nr00969k
• Languages: English
• ISSNs: 2040-3364

Abstract

Abstract : Synthesis and optical properties of large plasmonic satellites (>10 nm) covering a central dielectric particle. Abstract : Raspberry-like nano-objects made of large plasmonic satellites (>10 nm) covering a central dielectric particle have many potential applications as photonic materials, superlenses and (bio-) sensors, but their synthesis remains challenging. Herein, we show how to build stable and robust raspberry-like nano-systems with close-packed satellites, by combining monodisperse silica particles (80 or 100 nm diameter) and oppositely charged noble metal nanoparticles (Au or Ag) with well-defined sizes (10–50 nm). The spectral characteristics of their associated plasmonic resonances (wavelength, linewidth, extinction cross-section) and the electromagnetic coupling between satellites were observed using the spatial modulation spectroscopy technique and interpreted through a numerical model. The composite nano-objects exhibit numerous hot spots at satellite junctions, resulting in excellent surface-enhanced Raman scattering (SERS) performance. The SERS efficiency of the raspberry-like clusters is highly dependent on their structure.