Faceted Gold Nanorods: Nanocuboids, Convex Nanocuboids, and Concave Nanocuboids

Abstract

Au nanorods are optically tunable anisotropic nanoparticles with built-in catalytic activities. The state-of-the-art seed-mediated nanorod synthesis offers excellent control over the aspect ratios of cylindrical Au nanorods, which enables fine-tuning of plasmon resonances over a broad spectral range. However, facet control of Au nanorods with atomic-level precision remains significantly more challenging. The coexistence of various types of low-index and high-index facets on the highly curved nanorod surfaces makes it extremely challenging to quantitatively elucidate the atomic-level structure-property relationships that underpin the catalytic competence of Au nanorods. Here we demonstrate that cylindrical Au nanorods undergo controlled facet evolution during their overgrowth in the presence of Cu(2+) and cationic surfactants, resulting in the formation of anisotropic nanostructures enclosed by well-defined facets, such as low-index faceting nanocuboids and high-index faceting convex nanocuboids and concave nanocuboids. These faceted Au nanorods exhibit enriched optical extinction spectral features, broader plasmonic tuning range, and enhanced catalytic tunability in comparison to the conventional cylindrical Au nanorods. The capabilities to both fine-tailor the facets and fine-tune the plasmon resonances of anisotropic Au nanoparticles open up unique opportunities for us to study, in great detail, the facet-dependent interfacial molecular transformations on Au nanocatalysts using surface-enhanced Raman scattering as a time-resolved spectroscopic tool.

Electrochemical Reduction of N2 under Ambient Conditions for Artificial N2 Fixation and Renewable Energy Storage Using N2/NH3 Cycle

“…The morphological characterization, obtained via transmission electron microscopy (TEM), reveals the morphology of the THH Au NRs. The blue shifts of the longitudinal plasmon and transverse peaks, compared to the published results, [21] suggest a decrease in the size of the products, which increases the number of exposed chemically active facets. The angles between the bases and bevels on a single THH Au NR were then measured, starting clockwise from the one labeled ( Figure S4, Supporting Information).…”

The alloying effect and AgCl-directing growth for synthesizing a trimetallic nanoring with improved SERS

“…[1][2][3][4][5][6][7] As is well know, their applications have strong dependences on their shape, size and composition. [1][2][3][4][5][6][7] As is well know, their applications have strong dependences on their shape, size and composition.…”

High-yield synthesis and fine-tuning aspect ratio of (200) faceted gold nanorods by the pH-adjusting method

“…9,22,23 Moreover, precise facet control is vital to the optimization of the catalytic performance of GNRs. Quantitative assignment of the crystallographic facets exposed on the surfaces of GNRs, however, has long been a subject under intense debate.…”