Atomically Precise Nanocluster Assemblies Encapsulating Plasmonic Gold Nanorods

Abstract

The self-assembled structures of atomically precise, ligand-protected noble metal nanoclusters leading to encapsulation of plasmonic gold nanorods (GNRs) is presented. Unlike highly sophisticated DNA nanotechnology, this strategically simple hydrogen bonding-directed self-assembly of nanoclusters leads to octahedral nanocrystals encapsulating GNRs. Specifically, the p-mercaptobenzoic acid (pMBA)-protected atomically precise silver nanocluster, Na [Ag (pMBA) ], and pMBA-functionalized GNRs were used. High-resolution transmission and scanning transmission electron tomographic reconstructions suggest that the geometry of the GNR surface is responsible for directing the assembly of silver nanoclusters via H-bonding, leading to octahedral symmetry. The use of water-dispersible gold nanoclusters, Au (pMBA) and Au (pMBA) , also formed layered shells encapsulating GNRs. Such cluster assemblies on colloidal particles are a new category of precision hybrids with diverse possibilities.

Optically coupled gold nanostructures: plasmon enhanced luminescence from gold nanorod-nanocluster hybrids

“…For example, attaching AuNCs to silver or gold spherical nanoparticles resulted in an improved photoelectric or photocatalytic performance of the nanoclusters. 7,40 In reverse, AuNCs were used to improve the photothermal 41,42 and/or optical 43,44 properties of AuNRs. Au and Ag nanoclusters were also assembled with plasmonic nanoparticles to study the alteration of their emission properties.…”

Molecular reactivity of thiolate-protected noble metal nanoclusters: synthesis, self-assembly, and applications

“…Self-assembly provides an alternative method to customize or enhance the materials properties and performance of metal NCs through the collective and synergistic effects of adjacent NCs in the assembly, which can be fabricated in different sizes, morphologies, symmetries, and orders. 106,108,[128][129][130][131]186 Since the self-assembly process of metal NCs is mainly governed by either the inter-cluster interactions/reactions or clusters' interactions/ reactions with the cross-linker ions/molecules, superstructures with 1D, 2D and 3D congurations have been constructed based on metal NCs by deliberately controlling such interactions/ reactions.…”

“…For example, Chakraborty et al assembled [Ag 44 ( p -MBA) 30 ] 4− around p -MBA protected Au nanorods (Au NRs) with a length of ∼30 nm and a width of ∼10 nm. 186 The preferential anchoring of [Ag 44 ( p -MBA) 30 ] 4− on the <110> facets of Au NRs via H-bonds was suggested to trigger the self-assembly of [Ag 44 ( p -MBA) 30 ] 4− , ultimately giving rise to a core-in-cage octahedral architecture of Au NR@Ag 44 NCs. In sharp contrast to Au NR directed self-assembly of [Ag 44 ( p -MBA) 30 ] 4− NCs, the self-assembly behaviour of Te nanowires (NWs) can be modulated by [Ag 44 ( p -MBA) 30 ] 4− NCs.…”

Self-Assembled Metal Nanoclusters: Driving Forces and Structural Correlation with Optical Properties

“…One of the recent studies by Pradeep’s group showed that simple hydrogen bonding could also direct the self-assembly of NCs using the previously discussed ligand p-MBA. Gold nanorods were functionalized with p-MBA, and Ag 44 NCs were allowed to interact with this GNR@p-MBA, which resulted in directed self-assembly ( Figure 6 A) [ 78 ]. Ag 44 NCs form assembly through H-bonding with carboxylic acid dimerization of the capped surface ligands.…”