Tensile strength of carbyne chains in varied chemical environments and structural lengths

Abstract

Carbyne and carbyne-based low-dimensional structures are promising for several applications including ultra-compact circuits and purification devices. Designing any applied carbyne-based structure requires a fundamental understanding of the mechanical strength of carbyne chains with different lengths at different temperatures and operating chemical environment. Here we use molecular dynamics simulations to investigate the strength of carbyne chains with different lengths at different temperatures. A theoretical framework based on statistical mechanics and molecular dynamics results is presented, proving a fast and insightful method for predicting the rupture force and its physical mechanism. The effect of water molecules' interaction is also studied on the mechanical properties and it is shown that both the tensile strength and rupture strain are improved by the water interaction. The results of this work can be used for designing and analyzing the robustness and reliability of various carbyne-based materials and applied devices for varies working conditions.

Structure and Properties of Chained Carbon: Recent Ab Initio Studies

“…Molecular dynamics under a microcanonical ensemble was used by Mirzaeifar et al [19] to study the strength of carbon chains of different dimensions at a variable temperature. It was found that the presence of H2O molecules improves the bond stability, resulting in higher values of mechanical Nowadays it is difficult to synthesize monoatomic carbon chains in any form.…”

Nonlinear Viscous Water at Nanoporous Two-Dimensional Interfaces Resists High-Speed Flow through Cooperativity

“…This force field has been used to study the mechanics of carbyne chain in different solvent conditions and shows good agreement with DFT calculations. 13,25,26 The mechanical response of two …”

“…4,8−12 Its constituent building block, carbyne, is a one-dimensional carbon allotrope that shows chemical stability in water environment in a wide range of temperatures. 1,13,14 Moreover, one type of graphyne material besides graphene has been successfully synthesized 11 and its mechanical strength can reach 50 GPa, 10 which is on the same order of magnitude as graphene 15,16 and suggesting applications for fast water filtration. However, considering that the loading force generated from the viscous drag is proportional to the throughput (vD 2 , as schematically shown in Figure 1a), the occurrence of water flow at a nanoscale pore can lead to forces that would easily exceed the material strength and rupture even materials as strong as graphene or graphyne.…”

“…This force field has been used to study the mechanics of carbyne chain in different solvent conditions and shows good agreement with DFT calculations. 13,25,26 The mechanical response of two graphyne systems ( Figure 1b) shows that, while the graphyne of the longer carbyne chain remains intact in flow, the other one of the shorter carbyne chain easily fails. Moreover, while the pristine graphyne shows no chemical interaction with water molecules, which agrees with our former study as the neutral or acid environment does not weaken the strength of the carbyne chain, 13 the two free ends of the ruptured chain are terminated by hydroxyl groups, leading to permanent rupture of the covalent bond (C−C).…”

“…It is also noted that for our current study we do not model strong basic conditions, which can significantly weaken the carbyne chain. 13 This motivates us to inspect the water viscosity by focusing on the structure of water molecules at the interface. We notice ( Figure 1c) that water within 20 Å from the graphyne shows higher mass density of 130% that of its bulk state.…”