Individually Silica‐Embedded Gold Nanorod Superlattice for High Thermal and Solvent Stability and Recyclable SERS Application

Abstract A facile method to fabricate 2D hexagonal monolayer superlattices of gold nanorods (GNRs) individually embedded in silica matrix on a substrate is developed. In this method, the cetyltrimethylammonium bromide (CTAB) bilayer‐coated GNRs are self‐assembled into a hexagonally packed monolayer superlattice on the substrate by slow evaporation in the presence of silica precursors in the solution at a highly acidic condition. The GNR superlattices fabricated by this method show excellent structural stability at high temperature as high as 500 °C and in solvents of a wide range of polarities including water, ethanol, toluene, and cyclohexane. The structural stability makes the GNR superlattices highly reusable surface‐enhanced Raman scattering (SERS)‐active substrates for sensitive molecular detection, well‐maintaining the SERS intensity over 10 cycles.