Plasmonic Planet–Satellite Analogues: Hierarchical Self-Assembly of Gold Nanostructures

Abstract

In the past few years, a remarkable progress has been made in unveiling novel and unique optical properties of strongly coupled plasmonic nanostructures, known as plasmonic molecules. However, realization of such plasmonic molecules using nonlithographic approaches remains challenging largely due to the lack of facile and robust assembly methods. Previous attempts to achieve plasmonic nanoassemblies using molecular ligands were limited to dipolar assembly of nanostructures, which typically results in polydisperse linear and branched chains. Here, we demonstrate that core-satellite structures comprised of shape-controlled plasmonic nanostructures can be achieved through self-assembly using simple molecular cross-linkers. Prevention of self-conjugation and promotion of cross-conjugation among cores and satellites plays a key role in the formation of core-satellite heteroassemblies. The in-built electromagnetic hot-spots and Raman reporters of core-satellite structures make them excellent candidates for surface-enhanced Raman scattering probes.

Enhancement of two-photon photoluminescence and SERS for low-coverage gold films

“…There are various strategies for the realization of hot spots, e.g., aggregation of NPs, satellite-systems [25,26], nanostructures fabricated by electron-beam lithography (EBL), and focused ion beam (FIB) milling. However, colloids aggregation is unpredictable random process that leads to alternating Raman enhancement and decreased reproducibility.…”

Surface‐Enhanced Raman Scattering‐Based Bioimaging

“…Recently, we reported a novel class of shape-controlled plasmonic nanostructures, namely, core-satellite structures, which was achieved through self-assembly using simple molecular cross-linkers (see fig. 11.5) [16].…”

“…Several computational and experimental studies have clearly demonstrated that the SERS Ef at these EM hot spots is upward of 10 8 , which is nearly four to six orders of magnitude higher than the corresponding individual nanostructures [16,54]. Despite significant efforts toward controlled assembly of plasmonic nanostructures, realizing scalable nanoparticle assemblies that offer highly uniform, isotropic, and stable SERS enhancement remains challenging.…”

“…accidentally discovered nearly 35 years ago, SERS continues to attract broad scientific and technological interest owing to its ever-expanding application landscape. a nonexhaustive list of applications includes trace chemical and biological detection, environmental monitoring, surface analysis, pharmaceutical tracking, and molecular bioimaging [12][13][14][15][16][17].…”

Kontrollierte Herstellung von Planet‐Satellit‐Nanostrukturen durch RAFT‐Sternpolymere

“…Neben dem menschlichen Streben nach äs-thetischen und geordneten Strukturen ist die Untersuchung der resultierenden physikalischen Eigenschaften solcher Systeme eine weitere Triebkraft in diesem Forschungsgebiet, die unter anderem zu Planet-Satellit-Nanostrukturen geführt hat. Diese Materialien wurden als Elemente für die Sensorik, [2] Hilfsgerüste zur selektiven Funktionalisierung von Nanopartikeln an spezifischen Halbseiten, [3] plasmonische Messbänder, [4] Substrate für die oberflächenverstärkte Raman-Streuung [5] und Agentien für den tumorspezifischen Wirkstofftransport [6] vorgeschlagen. Eine effiziente und flexible Syntheseroute zu Planet-Satellit-Strukturen ist jedoch Voraussetzung für die Erforschung und Verwendung dieser Architekturen.…”