Fig. 1. Schematic description of the preparation of the GNR-silica supercrystal nanocomposites. Upper panel: Preparation of the plasmonic substrate by the PDMS template-driven self-assembly process. (1) A 2 μL drop of GNR suspension was stamped with a PDMS template containing an array of micron-sized cavities. (2) The solvent was allowed to evaporate, leading to the assembly of GNRs into a smectic phase. (3) After drying, the template was removed. (4) Arrays of GNR supercrystals were obtained on the substrate. Lower panel: The process used to coat and infiltrate the GNR supercrystals with mesoporous silica. (5) The substrates were immersed in a growth solution containing TEOS, ammonia, and CTAB in 3 : 1 water : ethanol at 60 °C for 3 days. (6) Arrays of GNR supercrystals impregnated with mesoporous silica were obtained on the silicon substrate.
