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arXiv · 1512.08693

$\pi$-bonding-dominated energy gaps in graphene oxides

Ngoc Thanh Thuy Tran·Shih-Yang Lin·Olga E. Glukhova·Ming-Fa Lin
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Abstract

Chemical bondings of graphene oxides with oxygen concentration from 1\% to 50\% are investigated using first-principle calculations. Energy gaps are mainly determined by the competition of orbital hybridizations in C-C, O-O, and C-O bonds. They are very sensitive to the changes in oxygen concentration and distributions. There exists five types of $\pi$ bondings during the variation from the full to vanishing adsorptions, namely the complete termination, the partial suppression, the 1D bonding, the deformed planar bonding, and the well-behaved one. They can account for the finite and gapless characteristics, corresponding to the O-concentrations of $>$25\% and $<$3\%, respectively. The feature-rich chemical bondings dominate band structures and density of states, leading to diverse electronic properties.

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Ngoc Thanh Thuy Tran, Shih-Yang Lin, Olga E. Glukhova, Ming-Fa Lin. 2015-12-29. $\pi$-bonding-dominated energy gaps in graphene oxides. https://arxiv.org/abs/1512.08693

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