Tunable Electronic Properties of Nitrogen and Sulfur Doped Graphene: Density Functional Theory Approach

Abstract

We calculated the band structures of a variety of N- and S-doped graphenes in order to understand the effects of the N and S dopants on the graphene electronic structure using density functional theory (DFT). Band-structure analysis revealed energy band upshifting above the Fermi level compared to pristine graphene following doping with three nitrogen atoms around a mono-vacancy defect, which corresponds to p-type nature. On the other hand, the energy bands were increasingly shifted downward below the Fermi level with increasing numbers of S atoms in N/S-co-doped graphene, which results in n-type behavior. Hence, modulating the structure of graphene through N- and S-doping schemes results in the switching of “p-type” to “n-type” behavior with increasing S concentration. Mulliken population analysis indicates that the N atom doped near a mono-vacancy is negatively charged due to its higher electronegativity compared to C, whereas the S atom doped near a mono-vacancy is positively charged due to its similar electronegativity to C and its additional valence electrons. As a result, doping with N and S significantly influences the unique electronic properties of graphene. Due to their tunable band-structure properties, the resulting N- and S-doped graphenes can be used in energy and electronic-device applications. In conclusion, we expect that doping with N and S will lead to new pathways for tailoring and enhancing the electronic properties of graphene at the atomic level.

Computational Analysis of Nanostructures for Li-Ion Batteries

“…Their experimental results showed a similar situation as the charging capacity of N doped structures is more than the undoped micro and nano carbon balls. More recently, N and S co-doped graphene structures were studied theoretically using VASP code [26]. 3N doped graphene, 2N and 1S doped graphene, 1 N and 2 S doped graphene, and 3 S doped graphene structure were simulated with single vacancy site near the doped atoms as shown in Figure 8.…”

“…Single vacancy graphene structures with (a) 3 N, (b) 2 N and 1 S, (c) 2 S and 1 N, and (d) 3 S doping[26].…”

Edge Chemistry of Armchair Graphene Nanoribbons Containing Sulfur Functional Groups: Towards an Understanding of the Spin‐Dependent Electrochemistry

“…Besides, they also performed theoretical calculations, demonstrating that the bandgaps of chevron‐like ribbons depend on the control of sulfur into the graphite structure. Recently, the synthesis of sulfur doping and sulfur–nitrogen codoping in graphene has been reported . Wasalathilake et al., investigated the interactions between graphene and chain lithium polysulfides (Li 2 S 8 and Li 2 S 4 ) using first principles density functional theory (DFT) calculations.…”

Tuning the Nature of N-Based Groups From N-Containing Reduced Graphene Oxide: Enhanced Thermal Stability Using Post-Synthesis Treatments

“…Therefore, it is possible to modify these properties by tailoring its electronic structure. This might be achieved by chemical modifications of the graphene lattice [ 7 , 8 , 9 , 10 ], as well as by the decoration of its basal plane with inorganic nanoparticles leading to nanocomposites with applications in MRI [ 11 ], antimicrobial/antibacterial agents [ 12 , 13 ], cathode material for batteries [ 14 ] and biosensors [ 15 ], to name a few.…”