Periodically Modulated Size-Dependent Elastic Properties of Armchair Graphene Nanoribbons

Abstract

First-principles calculations were conducted on armchair graphene nanoribbons (AGNRs) to simulate the elastic behavior of AGNRs with hydrogen-terminated and bare edges. The results show width-dependent elastic properties with a periodicity of three, which depends on the nature of edge. The edge eigenstress and eigendisplacement models are able to predict the width-dependent nominal Young's modulus and Poisson's ratio, while the Clar structure explains the crucial role of edges in the periodically modulated size-dependent elastic properties.

Recent Progress in Graphene/Polymer Nanocomposites

“…Unlike armchair configuration, there is no plasticity occurring here, which is attributed to the local CC bonds fracturing after hexagonal lattice transforms into quasi‐rectangular shape by zigzag bond extension. Moreover, both the nominal Young's modulus of armchair graphene nanoribbon with or without hydrogen‐terminated edges rise with the increased ribbon width (as illustrated in Figure 2f), [ 55 ] because the negative edge Young's modulus could degrade the Young's modulus of graphene nanoribbon. As a result, the larger the size of graphene nanoribbon, the smaller the edge effect.…”

Unusual Width Dependence of Lattice Thermal Conductivity in Ultranarrow Armchair Graphene Nanoribbons with Unpassivated Edges

“…For the electrical properties, the armchair GNRs (AGNRs) show increased band gaps as the width decreases − in the nanoscale regime, providing opportunities for atomically controlling the features of gap-modulated semiconductor junctions . For the mechanical property, Young’s modulus demonstrates a general increasing trend as the width increases. − For the magnetic properties, compared to the nonmagnetic 2D planar graphene, zigzag GNRs (ZGNRs) have magnetic edges which can be modulated and the related properties are width-dependent. , GNRs are also 1D symmetry-protected topological materials characterized by the Z 2 invariant and the topological properties are closely related to the width. , Thus, it is very fundamental yet essential to investigate the width dependence of the physical properties of GNRs for the multiple potential micro–nanodevices.…”

Terahertz nonlinear optical response of armchair graphene nanoribbons

“…Nearly-metallic acGNR are predicted to have a small band gap inversely proportional to their width L x [25,26]. However, the energy gaps reported in [5,[23][24][25][26][27][28][29][44][45][46][47][48][49] are functions of the different fabrication techniques, edge terminations and calculation methods used in these studies. We use the energy gap reported in [25] for thin m * GNR, as this band gap, induced by the asymmetry in the edge states, creates an onset energy offset ∓E g /2 in the A, B sublattice respectively in the low energy regime [32][33][34].…”

“…kink, twisting), etc. [23][24][25][26][27][28][29][30][31]. The prospect of band gap engineering in graphene nanoribbon leads to the long term goal of producing graphene nanoribbons on demand, and achieves top-down control of graphene nanostructuring [1].…”

“…The energy gap of these m * GNR is inversely proportional to their width [44][45][46][47]. Several theoretical models have predicted the energy gap based on different edge terminations and calculation methods [23][24][25][26][27][28][29].…”