Plasmonic Coupling: Wafer‐Scale Double‐Layer Stacked Au/Al₂O₃@Au Nanosphere Structure with Tunable Nanospacing for Surface‐Enhanced Raman Scattering (Small 19/2014)

A reproducible high-throughput approach is reported by J. J. Li, C. Z. Gu, and co-workers on page 3933 to fabricate wafer-scale double-layer stacked Au/Al2O3@Au(Ag) nanosphere structures with tunable nanospacing for surface-enhanced Raman scattering. This nanostructure constitutes a 3D plasmonic nanostructure with tunable nanospacing and high-density nanojunctions between adjacent Au nanospheres of ultrathin Al2O3 isolation layers, producing highly strong plasmonic coupling so that the electromagnetic near-field is greatly enhanced to obtain a uniform increase of SERS with an enhancement factor of over 108.