Rich geometric and electronic properties of graphene oxides
Tran Ngoc Thanh Thuy1*, Lin Shih-Yang1, Lin Ming-Fa1
1Physics, National Cheng Kung University, Tainan, Taiwan
* presenting author:Ngoc Thanh Thuy Tran,
The objective is to investigate the geometric and electronic properties of graphene oxides with different layers and stackings using first-principle calculations. Various charge distributions, oxygen positions, C-C and C-O bond lengths strongly depend on different oxygen coverages and number layers of graphene. The curvature effects and the epoxide bonds compete with each other to determine the rich electronic properties. The energy bands exhibit a lot of features, including the destruction of Dirac cone, opening of band gap, induced critical points, and dominating energy dispersions by oxygen. Their originations are studied in detail through the analysis on the chemical bonding. Whether graphene oxides are semiconductors or semi-metals are mainly determined by the position and density of oxygen. Furthermore, there exist certain important differences between graphene oxides and pure graphenes.

Keywords: graphene oxides, first-principles, band gap, Dirac cone, charge distribution