Hotspot‐Engineered 3D Multipetal Flower Assemblies for Surface‐Enhanced Raman Spectroscopy

Abstract

Novel 3D metallic structures composed of multipetal flowers consisting of nanoparticles are presented. The control of surface plasmon hotspots is demonstrated in terms of location and intensity as a function of petal number for uniform and reproducible surfaceenhanced Raman spectroscopy (SERS) with high field enhancement.

Three-dimensional SERS hot spots for chemical sensing: Towards developing a practical analyzer

“…According to theoretical simulations ( Figure 5), the liquid adhesive force can promote a closely packed assembly of particles, and the interparticle distance is not fixed but can be balanced in a small range, which results in a large number of hotspots in a 3D geometry. This kind of 3D hotspot matrix not only produces a Raman enhancement of 10 7 -10 8 , [2,3,45,48] but also provides the structural basis for trapping molecules.…”

“…(Reprinted with permission from[2,3,11,14,16,45,50,68,77,83]) Self-assembling fabrication and characterization of 3D plasmonic structures. (A) Top, Schematic depicting the self-assembly of polystyrene-stabilized metallic NPs into clusters.…”

Top-down patterning and self-assembly of flower-like gold arrays for surface enhanced Raman spectroscopy

“…Compared to smooth and random SERS substrates, these ordered metallic arrays could generate high electric field enhancement, and achieve broadband and unidirectional excitation of SPPs, even at normal incidence [10][11][12]. However, ordered metallic arrays based bottom-up approach face significant challenge of producing reproducible and uniform arrays [13], while, top-down approach such as electron or ion beam lithography could produce more uniform and reproducible nanostructures. But these techniques not only require time consuming serial processing in vacuum, but also are limited and very costly due to the requirements of specialized equipment with controlled environments [14,15].…”

Engineering 3D Multi-Branched Nanostructures for Ultra- Sensing Applications

“…Various nanofabrication methods, applying both bottom-up and top-down approaches, have been used to fabricate SERS-based platforms for sensing applications [38][39][40][41][42][43][44][45][46]. Among them, colloidal techniques provide a wide variety of nanoparticles with sharp protrusions, although they are still suffering for poor control over uniformity and arrangement [35].…”