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arXiv · 1503.02605

First-Principle Study of Dislocation Slips in Impurity Doped Graphene

Fanchao Meng·Bin Ouyang·Jun Song
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Abstract

Employing density-functional theory (DFT) calculations, the generalized-stacking-fault energy (GSFE) curves along two crystallographic slips, glide and shuffle, for both pristine graphene and impurity of boron (B) or nitrogen (N) doped graphene were examined. The effects of B and N doping on the GSFE were clarified and correlated with local electron interactions and bonding configurations. The GSFE data were then used to analyze dislocation dipole and core structure, and subsequently combined with the Peierls-Nabarro (P-N) model to examine the role of doping on several key characteristics of dislocations in graphene. We showed that the GSFE curve may be significantly altered by the presence of dopants, which subsequently leads to profound modulations of dislocation properties, such as increasing spontaneous pair-annihilation distance and reducing resistance to dislocation slip. Our results indicate that doping can play an important role in controlling dislocation density and microscopic plasticity in graphene, thereby providing critical insights for dopant-mediated defect engineering in graphene.

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Fanchao Meng, Bin Ouyang, Jun Song. 2015-03-09. First-Principle Study of Dislocation Slips in Impurity Doped Graphene. https://doi.org/10.1021/jp512364p

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