Self-assembly of plasmonic nanostructures into superlattices for surface-enhanced Raman scattering applications

Since the initial discovery that the interparticle nanogaps in nanoparticle aggregates was the surface-enhanced Raman scattering (SERS) hotspots that facilitated the enormous enhancements in SERS, the controllable assembly of plasmonic nanoparticles into superstructures is recognized as the most effective strategy for fabricating SERS substrate. The homogenous distribution abundant SERS hotspots inside the self-assembly reproducibly amplify the SERS signal. This ultimately makes SERS an ultrasensitive analytical method with the potential to elicit fundamental chemistry, biology, and physics breakthroughs. This review focuses on recent developments in self-assemble of plasmonic NPs for SERS applications, including: 1) Template-guided self-assemble of plasmonic NPs 2) Templateless self-assemble of plasmonic NPs 3) Taking full advantage of the assembly process: integration of target analyte recognition and capture capacity into the assembly 4) Assembly makes perfect: new opportunities created by large self-assembling SERS substrates. 5) Future directions and possible applications of self-assembled SERS substrates.