Mode-Selective Plasmon Coupling between Au Nanorods and Au Nanospheres

Abstract

Plasmons play a central role in the properties of gold nanoparticles (AuNPs). Plasmons in a AuNP are influenced by neighboring ones, resulting in hybridized bonding dipole modes and red-shifted resonance peaks in the extinction spectra. Previous studies have mainly focused on plasmon coupling among spherical AuNPs (AuNSs). Here, we explore plasmonic interactions between AuNSs and anisotropic gold nanorods (AuNRs), which have longitudinal (LO) and transverse (TR) plasmon modes. We successfully assemble AuNSs around AuNRs (“AuNR@AuNS”), observing shifts in both the LO and TR modes in the extinction spectra due to directional coupling. Selectively binding AuNSs to the ends of AuNRs (“AuNRAuNS”) leads to predominant plasmon coupling along the LO direction. Our simulation studies reveal that exclusive LO or TR coupling occurs only when AuNSs attach to the center of either the end or the side of AuNRs. This study provides a valuable guideline for selectively exciting plasmons in desired nanogaps when multiple nanogaps are present.

Rapid formation of gold core–satellite nanostructures using Turkevich-synthesized satellites and dithiol linkers: the do's and don'ts for successful assembly

“…Through variations to the (i) size, shape, and composition of the core, (ii) the number, size, composition, and position of satellites, and (iii) the core–satellite and satellite–satellite spacing, there exists a design space that gives rise to an overall architectural diversity that expresses itself in the resulting structure–property relationships. 14,18–26 Nanospheres, 14,18,19 nanorods, 20–22 nanocubes, 23 nanotriangles, 24 and nanostars 25,26 have, for example, all been demonstrated as core materials utilizing either Au or Ag nanostructures as component materials. In another impressive demonstration, Trinh et al 27 forwarded a combinatorial approach that realizes a complex assortment of substrate-based core–satellite structures from nine different building blocks.…”

Seeded Growth of AuPt-PdAg Solid–Hollow Hybrid Nanocrystals and Their Applications in Plasmon-Enhanced Catalysis

“…Previous studies have primarily concentrated on the structural design of individual-particle systems. However, recent advancements suggest that the hybrid integration of structural components with diverse characteristics into a unified entity can offer more versatile control over the overall physiochemical properties due to a synergistic effect. , For instance, the proximity of neighboring particles or surfaces can elicit coupling effects that modulate the plasmon resonance . The shape of the particle will dictate how it interacts with adjacent structures, further impacting the near-field distribution.…”