Thermal stability of platinum nanowires: a comparison study between single-crystalline and twinned structures

Abstract

Platinum is the most active and one of most commonly used catalytic metals. In this article, atomistic simulations have been employed to systematically investigate the thermal stability of platinum nanowires with single-crystalline and fivefold twinned structures. It has been revealed that the single-crystalline nanowires possess better structural stabilities than the twinned ones. Furthermore, when subjected to continuous heating, the twinned nanowires exhibit an inhomogeneous melting, essentially different from what happens in the single-crystalline ones, and hence the lower melting point. By analyses of the microstructural evolution and dynamics behavior during the heating process, the structural transition of the nanowire is discussed and the inhomogeneity in the twinned nanowire is identified to originate from the dislocation-induced destruction of twin boundaries.National Natural Science Foundation of China[20833005, 21021002]; Natural Science Foundation of Fujian Province of China[2011J05011

Flexible transparent conductive materials based on silver nanowire networks: a review

“…This is a case of classical interfacial instability when dealing with liquid or solid cylinders when heated, called the Plateau-Rayleigh instability [127]. The morphological evolution of metallic NWs have been intensively investigated recently for Au [128], Cu [129], Pt [130], Sn [131], or Ag [132]. In a simple approach, perturbations with wavelengths larger than the original cylinder diameter become unstable.…”

Effect of grain size on the melting point of confined thin aluminum films

“…Most often a value in the range of 0.1-0.15 is used for similar materials. 57 Melting point is, in fact, a macroscopic concept, defined as the temperature at which a solid becomes liquid. Because of the finite size, however, melting occurs over a range of temperatures, in which the solid and liquid phases coexist with different fractions.…”

“…[52][53][54][55][56] Only a few describe the effect of grain boundaries. [57][58][59][60] The situation is complicated by two opposite effects: (a) grain boundaries which lower the melting point and (b) confinement in material with a coherent interface, which leads to superheating. 61 In order to have a better insight into the interplay of these two, a comprehensive model employing molecular dynamic (MD) simulations was developed and its results are reported here.…”

Study of the Mechanical Behavior of Radially Grown Fivefold Twinned Nanowires on the Atomic Scale

“…The strength has been significantly enhanced after introducing effective obstacles, which serve as blocks for dislocation motion . Fivefold twins, one of the most important twinned structures, have attracted considerable attention recently . Cyclic mechanical behavior tests showed a Bauschinger effect that occurred due to the pentatwinned structure and a reversible dislocation activity in fivefold‐twin structured Ag nanowires was found .…”

“…However, in‐situ experimental data have not been able to demonstrate the mechanical behavior on the atomic scale up until now, which might go against our understanding of the mechanical behavior of such fivefold‐twin structured materials. Direct experimental demonstration of the deformation mechanism faces two challenges: firstly, an in situ deformation test is difficult to be conducted on the atomic scale; secondly, in most cases, the fivefold twins grow along the axial direction both in the experimental and simulation results . This means that the central area of these axially grown, fivefold‐twin, grain‐boundary structures cannot be experimentally monitored in bending or tensile/compressive tests on the atomic scale .…”