Twisting Ultrathin Au Nanowires into Double Helices

Abstract

Previously, double helix nanowire was reported by coating Pd/Pt/Au onto Au-Ag alloy nanowire. Here, straight oleylamine-stabilized ultrathin Au nanowires with single crystalline fcc lattice are surprisingly converted into double helix helices upon reacting with Ag in tetrahydrofuran (THF). The obtained Au-Ag helical nanowires contain lattice distinctively different from the fcc lattice and are different in many aspects with the previous system. The discovery may expand the scope of nanoscale double helix formation and the understanding of lattice transformation among ultrafine nanostructures.

Braiding Ultrathin Au Nanowires into Ropes

“…Previously, our group twisted individual ultrathin nanowire into a self-intertwined double helix with characteristic U-turn ends: upon metal deposition, a Au-Ag alloy nanowire with a Boerdijk−Coxeter−Bernal (BCB) lattice 11,12 untwisted toward the face-center-cubic ( fcc) lattice, 13 or an ultrathin Au nanowire with fcc lattice twisted toward possibly BCB-type lattices. 14 Applying such individual twisting behavior to the collective motion of multiple strands would be an interesting scientific challenge. With such a "remote" control, we could explore the braiding and weaving of inorganics at the nanoscale.…”

“…Some small Au nanoparticles are byproducts existing among the nanowires. Twisting of Au nanowires was induced with metal deposition, 13,14 or more specifically by reducing Na 2 PdCl 4 with L-ascorbic acid. The color of the solution gradually turned from light pink to dark brown in 2 h, indicating the deposition of metallic Pd.…”

“…To our great interest, the reaction caused the bundles to form nanoropes (Figures 1b,j,k and S2), in contrast to the self-intertwined nanohelices with multiple Uturns. 13,14 The originally parallel stripes turned to helical patterns with uniform curvature. The nanowires were highly interlaced, and the patterns varied depending on the number of strands in the bundle.…”

Facile morphology control of gold(0) structures from aurophilic assemblies

“…28 On the other hand, we also reported the reduction of gold(I) organometallic supramolecular assemblies to well-controlled Au(0) nanoparticles with different sizes upon irradiation of light, electrons or temperature. 21 The combination of inter-and intramolecular electrostatic and Au(I)•••Au(I) aurophilic and other type of weak interactions define the path for the alignment of the assemblies and constitutes the driving force for the morphological transformation under certain conditions [29][30][31][32] . But, besides nanoparticle or nanocluster formation, it has been reported in the literature that the presence of aurophilic contacts between AuCl(oleylamine) molecules can also induce the formation of very thin nanowires when the reduction is performed by using silver NPs.…”

Poly(Ethylene Oxide) Mediated Synthesis of Sub-100-nm Aluminum Nanocrystals for Deep Ultraviolet Plasmonic Nanomaterials

“…During the syntheses, organic ligands could control the nucleation and preferential growth facets of nanoparticles effectively via organic−inorganic interface absorption on specific crystal facets. [34][35][36][37][38][39][40][41] Recently, our group reported the use of an end-group functionalized polymer, cumyl dithiobenzoate-terminated polystyrene (CDTB-PS), as a surface ligand for the morphology-and size-controlled synthesis of monodisperse Al NCs with a wide size range from 130 to 250 nm. 42 However, Al NCs in this size range exhibited multiple plasmonic peaks, including dipolar plasmonic resonances in the vis-NIR region and high-order plasmonic resonance in the UV region.…”