Oxygen density dependent band gap of
reduced graphene oxide
Haiming Huang, Zhibing Li, Juncong She, Weiliang Wang
State Key Lab of Optoelectronic Materials and Technologies, School of Physics and
Engineering, Sun Yat-sen University, Guangzhou 510275, People’s Republic of
China.

Corresponding author: Telephone and fax number: +86 020 84112878. E-mail:
wangwl2@mail.sysu.edu.cn
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FIG. S1. (Color online) The atomic structure and total density of states (arbitrary
units) for RGO with the oxygen coverage of 6.25% (C64O4). (a) The most stable
configuration and its DOS. The left panel is the atomic structure and the right panel is
the total DOS. (b) and (c) are the same as (a) but for the second most and the third
most stable configuration respectively. The gray spheres at the nodes of the hexagonal
lattice are carbon atoms, and the red spheres on C-C bonds represent oxygen atoms.
The blue solid lines indicate the supercells. The Fermi level (indicated via dash lines)
has been set to zero.
2
FIG. S2. (Color online) The atomic structure and total density of states (arbitrary
units) for RGO with the oxygen coverage of 10% (C30O3). (a) The most stable
configuration and its DOS. The left panel is the atomic structure and the right panel is
the total DOS. (b) and (c) are the same as (a) but for the second most and the third
most stable configuration respectively. The gray spheres at the nodes of the hexagonal
lattice are carbon atoms, and the red spheres on C-C bonds represent oxygen atoms.
The blue solid lines indicate the supercells. The Fermi level (indicated via dash lines)
has been set to zero.
3
FIG. S3. (Color online) The atomic structure and total density of states (arbitrary
units) for RGO with the oxygen coverage of 11.1% (C18O2). (a) The most stable
configuration and its DOS. The left panel is the atomic structure and the right panel is
the total DOS. (b) and (c) are the same as (a) but for the second most and the third
most stable configuration respectively. The gray spheres at the nodes of the hexagonal
lattice are carbon atoms, and the red spheres on C-C bonds represent oxygen atoms.
The blue solid lines indicate the supercells. The Fermi level (indicated via dash lines)
has been set to zero.
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FIG. S4. (Color online) The atomic structure and total density of states (arbitrary
units) for RGO with the oxygen coverage of 12.5% (C32O4). (a) The most stable
configuration and its DOS. The left panel is the atomic structure and the right panel is
the total DOS. (b) and (c) are the same as (a) but for the second most and the third
most stable configuration respectively. The gray spheres at the nodes of the hexagonal
lattice are carbon atoms, and the red spheres on C-C bonds represent oxygen atoms.
The blue solid lines indicate the supercells. The Fermi level (indicated via dash lines)
has been set to zero.
5
FIG. S5. (Color online) The atomic structure and total density of states (arbitrary
units) for RGO with the oxygen coverage of 16.7% (C24O4). (a) The most stable
configuration and its DOS. The left panel is the atomic structure and the right panel is
the total DOS. (b) and (c) are the same as (a) but for the second most and the third
most stable configuration respectively. The gray spheres at the nodes of the hexagonal
lattice are carbon atoms, and the red spheres on C-C bonds represent oxygen atoms.
The blue solid lines indicate the supercells. The Fermi level (indicated via dash lines)
has been set to zero.
6
FIG. S6. (Color online) The atomic structure and total density of states (arbitrary
units) for RGO with the oxygen coverage of 20% (C30O6). (a) The most stable
configuration and its DOS. The left panel is the atomic structure and the right panel is
the total DOS. (b) and (c) are the same as (a) but for the second most and the third
most stable configuration respectively. The gray spheres at the nodes of the hexagonal
lattice are carbon atoms, and the red spheres on C-C bonds represent oxygen atoms.
The blue solid lines indicate the supercells. The Fermi level (indicated via dash lines)
has been set to zero.
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FIG. S7. (Color online) The atomic structure and total density of states (arbitrary
units) for RGO with the oxygen coverage of 25% (C8O2). (a) The most stable
configuration and its DOS. The left panel is the atomic structure and the right panel is
the total DOS. (b) and (c) are the same as (a) but for the second most and the third
most stable configuration respectively. The gray spheres at the nodes of the hexagonal
lattice are carbon atoms, and the red spheres on C-C bonds represent oxygen atoms.
The blue solid lines indicate the supercells. The Fermi level (indicated via dash lines)
has been set to zero.
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FIG. S8. (Color online) The atomic structure and total density of states (arbitrary
units) for RGO with the oxygen coverage of 27.8% (C18O5). (a) The most stable
configuration and its DOS. The left panel is the atomic structure and the right panel is
the total DOS. (b) and (c) are the same as (a) but for the second most and the third
most stable configuration respectively. The gray spheres at the nodes of the hexagonal
lattice are carbon atoms, and the red spheres on C-C bonds represent oxygen atoms.
The blue solid lines indicate the supercells. The Fermi level (indicated via dash lines)
has been set to zero.
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FIG. S9. (Color online) The atomic structure and total density of states (arbitrary
units) for RGO with the oxygen coverage of 50% (C4O2). (a) The most stable
configuration and its DOS. The left panel is the atomic structure and the right panel is
the total DOS. (b) is the same as (a) but for the second stable configuration. The gray
spheres at the nodes of the hexagonal lattice are carbon atoms, and the red spheres on
C-C bonds represent oxygen atoms. The blue solid lines indicate the supercells. The
Fermi level (indicated via dash lines) has been set to zero.
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