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arXiv · 1404.6446

First-principles DFT study for the structural stability of Hydrogen passivated graphene (H-graphene) and atomic adsorption of oxygen on H-graphene with different schemes

Deepak B Karki·Narayan P Adhikari
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Abstract

First-principles DFT levels of calculations have been carried out in order to study the structural stability and electronic properties of hydrogen passivated graphene (H-graphene) clusters. Two different shaped clusters, rectangular and circular, consisting of 6 to 160 carbon atoms and hydrogen termination at the zigzag boundary edges have been studied. The relative stability of rectangular shaped cluster consisting 96 C-atoms found to be 1.5% greater than that of circular shape cluster consisting same number of C-atoms. In comparing circular and rectangular cluster containing same number of C-atoms, the HOMO-LUMO gap of former have been predicted to be 2.159 eV and that of later just 0.346 eV. Adsorption of oxygen atom on H-graphene with different schemes including single sided, both sided and high concentration adsorption, was also studied systematically through first-principles DFT calculations by taking four different H-graphene clusters.

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Deepak B Karki, Narayan P Adhikari. 2014-05-01. First-principles DFT study for the structural stability of Hydrogen passivated graphene (H-graphene) and atomic adsorption of oxygen on H-graphene with different schemes. https://arxiv.org/abs/1404.6446

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