Abstract
First-principles density functional theory calculations are performed on dopamine-graphene systems in the presence of an external electric field. The graphene lattice is also modified via substitutional boron-and nitrogen-doping, and via the introduction of defects (monovacancy and Thrower-Stone-Wales). The geometry optimization, electronic density of states, cohesive energy, electronic charge density, and wave functions are analyzed. Our results revealed that dopamine is anchored on the surface of graphene via a physisorption mechanism, and the cohesive strength varies as B-doped > N-doped > vacancy defect > Thrower-Stone-Wales defect. Boron-doped graphene exhibits valence states with dopamine molecules; furthermore, this system showed the strongest cohesive energy. When an electric field is applied, we observe shifts in the valence states near the Fermi level producing a decrease in the molecule-layer interaction. We envisage that the present results could help in developing novel biosensors based on doped/defective graphene field-effect transistor devices.
Original language | English (US) |
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Pages (from-to) | 13972-13978 |
Number of pages | 7 |
Journal | Journal of Physical Chemistry C |
Volume | 119 |
Issue number | 24 |
DOIs | |
State | Published - Jun 18 2015 |
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Energy(all)
- Physical and Theoretical Chemistry
- Surfaces, Coatings and Films