Composition and lattice structure of fivefold twinned nanorods of silver

Abstract

Multiply twinned silver particles of rod-like shape and nanometer dimensions prepared by inert-gas aggregation technique have been studied by high-resolution electron microscopy. These pentagonal nanorods exhibit aspect ratio between 1.8 and 6 with the length of their fivefold axis ranging from 22 to 132 nm. Digital image processing and evaluation was utilised to characterise composition and lattice structure of the nanorods. Measuring the spacings of lattice plane fringes of nanorod subunits in various orientations revealed no deviation from the face centred cubic lattice type. There was also no indication of extended lattice defects found. Instead, a certain extent of non-regular lattice distortions recognised in the surface regions of the nanorods apparently is an effective means to achieve sufficient space filling. r

Metastability of multitwinned Ag nanorods: Molecular dynamics study

“…11 The analytical model includes the energy of the dipyramidal structure at both ends of the nanowire because the majority of experimental studies show growth along two dipyramidal ends. 7,9,12,20 The ends are also considered for the nontwinned nanorod, which was assumed to be a truncated octahedron, consistent with the Wulff construction. The end structures for the nontwinned nanorod are shown in Fig.…”

“…[4][5][6] The current study focuses on silver ͑Ag͒ nanowires, which have great potential for higher strengths due to the existence of multiple twinned structures. [7][8][9][10][11] The increased strength in the multitwinned nanorods has been attributed to the twinned structure's ability to hinder dislocation motion and generate work hardening in the material. 1,12 Multitwinned particulates are used as seeds to grow multitwinned nanorods ͑MTRs͒ and have been observed for over half a century starting with their discovery by Ino in 1966.…”

“…Hofmeister et al 9 used high-resolution transmission electron microscopy ͑HRTEM͒ to study elastic strains in Ag and Au nanowires with lengths in the range of 22-132 nm and aspect ratios of 1.8-6.0. The authors observed no extended defects and instead found nonuniform lattice distortions beneath the prism surface.…”

Interactive effect of agitation rate and oxidative etching on growth mechanisms of silver nanowires during polyol process

“…It was reported that silver one-dimensional (1D) nanostructure consists of arranged subunits around a fivefold axis instead of a single crystal. [17] The uniaxial growth of silver nanowires was illustrated based on Ag:O coordination of the absorbed polyvinylpyrrolidone (PVP) on Ag nanowires' surfaces. [18] Furthermore, the growth mechanisms of Ag nanostructures via microwave-polyol method in the presence of Pt as the catalyst have been studied.…”

Electron Diffraction and HRTEM Structure Analysis of Nanowires

“…The important role of twinning in determining the habit of the final morphology will also be discussed. One interesting feature of silver, gold, and copper pentagonal cross-section nanowires, is their remarkable structure (Gao et al, 2003;Giersig et al, 2004;Hofmeister et al, 2002;Sun et al, 2002;Zhao et al, 2005). It has been proposed that this structure evolved from a multi-twin decahedral nanoparticle growing in the [110] direction by stabilizing more effectively the newly formed 100 facets than the 111 facets and their electron diffraction patterns present "forbidden" spots.…”