Growth Mechanism of Five-Fold Twinned Ag Nanowires from Multiscale Theory and Simulations

Abstract

Five-fold twinned metal nanowires can be synthesized with high aspect ratios via solution-phase methods. The origins of their anisotropic growth, however, are poorly understood. We combine atomic-scale, mesoscale, and continuum theoretical methods to predict growth morphologies of Ag nanowires from seeds and to demonstrate that high aspect ratio nanowires can originate from anisotropic surface diffusion induced by the strained nanowire structure. Nanowire seeds are similar to Marks decahedra, with {111} "notches" that accelerate diffusion along the nanowire axis to facilitate one-dimensional growth. The strain distribution on the {111} facets induces heterogeneous atom aggregation and leads to atom trapping at the nanowire ends. We predict that decahedral Ag seeds can grow to become nanowires with aspect ratios in the experimental range. Our studies show that there is a complex interplay between atom deposition, diffusion, seed architecture, and nanowire aspect ratio that could be manipulated experimentally to achieve controlled nanowire syntheses.

Computational assessment of the efficacy of halides as shape-directing agents in nanoparticle growth

“…This can yield anisotropic shapes, since growth can be hampered in the case of high coverage. In a kinetically controlled synthesis, in which the surface diffusion is slow compared to the arrival rate of monomers at the surface, this would promote growth on {111} and turn octahedra into cubes [70] while increasing the aspect ratio of decahedra [71,72]. control parameters.…”

Nanowire Genome: A Magic Toolbox for 1D Nanostructures

“…The polyol synthesis has been developed as one of the most popular and versatile methods for the production of Ag NWs. The polyol reduction process usually contains the reduction of an Ag precursor in a homogeneous liquid medium with the assistance of a surfactant, such as PVP ( Figure a), which strongly bonds to the side planar of Ag NWs to facilitate the anisotropic growth and prevent the NWs from aggregating . Early in 2002, the Xia group made significant progress in the large‐scale synthesis of Ag NWs with a controlled diameter of 30–40 nm and lengths up to 50 µm through a solution‐phase process (EG act as both the solvent and the reducing agent) .…”

“…Recently, remarkable progress has been made in research focused on the synthesis of Ag NWs, leading to well-controlled morphologies and aspect ratios. [200][201][202] Currently, Ag NWs are successfully synthesized by a variety of chemical approaches, such as the template synthesis, [203,204] ionic-liquid-assisted synthesis, [205] microwave-assisted aerobic synthesis, [206] and polyol reduction process. [196,199,207,208] All in all, Ag NWs show a diameter range from 10 to more than 100 nm and an aspect ratio as large as 2000.…”

“…The polyol reduction process usually contains the reduction of an Ag precursor in a homogeneous liquid medium with the assistance of a surfactant, such as PVP (Figure 9a), which strongly bonds to the side planar of Ag NWs to facilitate the anisotropic growth and prevent the NWs from aggregating. [196,202] [196] Copyright 2003, American Chemical Society. b) TEM images of Ag NWs with an average diameter of 13 nm.…”

Molecular Dynamics Study on Mechanical Properties of Nanopolycrystalline Cu–Sn Alloy

“…In recent decades, the alloys with nano-scale grains have attracted lots of researchers due to their excellent exceptional mechanical properties. With the rapid development of material technology, and the further improvement of the requirements of engineering application for material properties, nanocrystalline materials have attracted the increasing attention of many researchers [7,8]. However, nanopolycrystalline Cu-Sn alloys are seldom studied.…”