Bottom-Up Synthesis of Gold Octahedra with Tailorable Hollow Features

Langille, Mark R.; Personick, Michelle L.; Zhang, Jian; Mirkin, Chad A.

doi:10.1021/ja204375d

Cited by 72 publications

(72 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…26 Among them, the isotropic shaped NCs have been systematically studied by many research groups, 20 and the extensive studies are moving the focus towards to anisotropic structures. [37][38][39][40][41][42][43][44] These solids are categorized in terms of the ancient Greek scientists and very mathematical aesthetics and symmetry in geometry. [37][38][39][40][41][42][43][44] These solids are categorized in terms of the ancient Greek scientists and very mathematical aesthetics and symmetry in geometry.…”

Section: Introductionmentioning

confidence: 99%

Hydrothermal synthesis of gold polyhedral nanocrystals by varying surfactant concentration and their LSPR and SERS properties

et al. 2015

View full text Add to dashboard Cite

Several polyhedral gold nanocrystals (Au NCs) whose geometric morphology belongs to the Platonic solid and Archimedean solid groups are synthesized by modulating the cetyltrimethylammonium bromide (CTAB) concentration in the designed hydrothermal processes. The mechanism of growth of these polyhedral Au NCs is revealed via crystallographic analyses, which suggest that their morphologies mainly depend on the diminishing of the surface energy of the specific facets in the CTAB-directive shape-control process. Furthermore, the localized surface plasmon resonance (LSPR) properties of the as-prepared polyhedral Au NCs are numerically assessed using the finite element method (FEM). The calculations show that these polyhedral Au NCs exhibit geometry-dependence plasmonic properties: specifically, the enormous local field enhancements occur around their vertices and corners. The SERS spectra of 4-mercaptobenzoic acid molecules adsorbed on these polyhedral Au NCs display superior SERS activity with an enhancement factor of 10 5 to 10 6 at the excitation wavelength of 785 nm. Particularly, the truncated tetrahedron and bitetrahedron show higher SERS enhancement factors due to their LSPR being closer to the excitation wavelength of 785 nm. Thus, the facile surfactant-assisted synthesis offers the opportunity to design and optimize the shape-dependent SERS activity of polyhedral Au NCs with respect to possible applications in bio-sensing and imaging.

show abstract

Section: Introductionmentioning

confidence: 99%

Hydrothermal synthesis of gold polyhedral nanocrystals by varying surfactant concentration and their LSPR and SERS properties

et al. 2015

View full text Add to dashboard Cite

show abstract

“…[16,17] The need to produce nanoparticles (NPs) with finely tuned optical properties has therefore led to enormous research efforts to develop reliable routes to synthesize noble metal NPs with controllable shapes and sizes. To tailor the nanoparticle properties and improve their performance in various applications, people have developed many chemical methods for generating Au and Ag nanocrystals with a rich variety of shapes, including sphere, [18] rod, [19] wire, [20] prism, [21,22] cube, [23] octahedron, [24] star, [25] icosahedron, [23,26] and bipyramid. [27] Bimetallic Ag and Au nanocrystals are particularly attractive because they possess a broader range of plasmon tunability and versatile surface functionalities than does the individual unit of a Ag or Au nanocrystal.…”

Section: Introductionmentioning

confidence: 99%

Gold Coating of Silver Nanoprisms

Shahjamali

Bosman

Cao

et al. 2012

Adv Funct Materials

119

120

View full text Add to dashboard Cite

Core–shell Ag@Au nanoprisms are prepared through a surfactant‐free seed‐mediated approach by taking advantage of the anisotropic structure of silver nanoprisms as seeds. The gold coating on the silver nanoprism surface is achieved by using hydroxylamine as a mild reducing agent, and the final fully gold‐coated prism structures are confirmed by microscopic and spectroscopic characterization. The resulting Ag@Au core–shell structure preserves the optical signatures of nanoprisms and offers versatile functionality and particularly better stability against oxidation than the bare silver nanoprism. The surface plasmon resonances of the core–shell Ag@Au nanoprisms can be tuned throughout the visible and near‐IR range as a function of the Au shell thickness. Such tailorable optical features and surfactant‐free gold shells have great potential applications in biosensing and bioimaging.

show abstract

“…Generally, control over nanoparticle morphologies can be implemented at different development stages: nucleation (least understood in terms of shape control), 1,11,15,16 nuclei growth (reasonably well developed), [17][18][19] and post-synthetic transformations of nanoparticles (well-understood and practically realized within the limits imposed by transformed morphologies). 20,21 It is established that the growth of several types of metal nanoparticle morphologies is kinetically driven via fast growth directions originated from twinned defects. 12,15,22,23 One of such morphologies is platelets/prisms, where planar twinned defects serve as fast growth/dissolution loci.…”

Section: Introductionmentioning

confidence: 99%

Multifaceted prismatic silver nanoparticles: synthesis by chloride-directed selective growth from thiolate-protected clusters and SERS properties

Cathcart

Kitaev

2012

Nanoscale

View full text Add to dashboard Cite

We describe the synthetic preparation of well-defined symmetric multifaceted prismatic silver nanoparticles with chemically controlled faceting advantageous for strong and tunable surface-enhanced Raman scattering, SERS. These silver nanoparticles, that have been termed nanoflowers, AgNFls for their characteristic morphologies, have been prepared by a one-pot aqueous reaction under ambient conditions. AgNFl faceting is synthetically controlled by selective nanoparticle growth driven by chloride ions. Selective chloride binding to the surface of growing AgNFls results in nanoparticle enlargement predominantly at the points of their highest energy. These growth points are located at the tips of prismatic polygons in precursor prismatic morphologies that have been produced from thiolate-protected silver clusters whose coalescence is triggered with a strong base. For the practical aspects of AgNFl synthesis, concentrations of thiol and a strong base were found to be the key variables reliably controlling the extent of AgNFl faceting, as well as the kinetics of AgNFl formation and their stability. The selective growth of AgNFls progresses slower compared to that of non-faceted prisms: fewer nuclei can form leading to larger AgNFls with the diameter ranging from 130 to 2250 nm and asperity sizes on the order of 20 to 100 nm. Self-assembly of AgNFls yields columnar stacking. AgNFls were demonstrated to function as a promising substrate for surface-enhanced Raman scattering. SERS measurements were performed for a series of AgNFls with variable faceting, where the enhancement factors of 4.6 × 10(8) and 425 have been achieved for dry solid films and aqueous dispersions of non-aggregated AgNFls with single-particle enhancement, respectively. These SERS results are promising, especially in combination with that AgNFl nanoscale asperities can be conveniently tailored synthetically. Overall, AgNFls offer valuable opportunities for a system with synthetically variable nanoscale asperities.

show abstract

Bottom-Up Synthesis of Gold Octahedra with Tailorable Hollow Features

Cited by 72 publications

References 46 publications

Hydrothermal synthesis of gold polyhedral nanocrystals by varying surfactant concentration and their LSPR and SERS properties

Hydrothermal synthesis of gold polyhedral nanocrystals by varying surfactant concentration and their LSPR and SERS properties

Gold Coating of Silver Nanoprisms

Multifaceted prismatic silver nanoparticles: synthesis by chloride-directed selective growth from thiolate-protected clusters and SERS properties

Contact Info

Product

Resources

About