Modulating the electronic and magnetic structures of P-doped graphene by molecule doping

Abstract

The adsorption of gas molecules on P-doped graphene (PG) was theoretically studied using density-functional theory in order to find the possibility of modulating electronic and magnetic ordering of graphene. H₂, H₂O, CO₂, CO, N₂ and NH₃ molecules are physisorbed, while NO, NO₂, SO₂ and O₂ molecules are strongly chemisorbed on PG through the formation of P-X (X = O, N, S) bonds. P dopant introduces global spin polarization into graphene with order of 1.05 μ(B). Chemisorption of NO₂ and SO₂ makes the spin polarization and projected density of states (PDOS) of molecules localized. NO also induces a partly localized spin state and O₂ an unpolarized system. Meanwhile, the systems of NO₂ and O₂ on PG are metallic, while NO and SO(2) on PG are half-metallic. Therefore, the properties of PG are strongly dependent on the types of molecules adsorbed, and the method of combining foreign atom doping followed by exposure to air is effective for the engineering of graphene.

When noncovalent interactions are stronger than covalent bonds: Bilayer graphene doped with second row atoms, aluminum, silicon, phosphorus and sulfur

“…For example, we found that a band gap of 0.30 eV could be opened when a sulfur atom replaces a carbon atom in a 5 Â 5 graphene supercell [12], whereas a larger band gap was determined for P-doped graphene, even though Al-doped graphene is metallic [13]. The Pdoped and S-doped graphenes have outstanding properties to construct sensors for NO 2 and SO 2 [6,7]. However, Al-doped graphene is not expected to be a good candidate because it is too reactive.…”

“…This can be attained by electrochemical reaction with ammonia [3], chemical vapor deposition [4] or simultaneous Ndoping and reduction of graphene oxide [5]. In second place, the applications are largely motivated by the theoretic investigations [6][7][8][9][10][11][12][13] guiding in the identification of the materials whose synthesis would be easier and also unraveling the chemical properties of the new carbon based nanostructures that can be used in nanodevices. Recent publications showed that using sulfur or phosphorus atoms [6][7][8]12,13] it is possible to open a band gap in the band structure of graphene.…”

“…In second place, the applications are largely motivated by the theoretic investigations [6][7][8][9][10][11][12][13] guiding in the identification of the materials whose synthesis would be easier and also unraveling the chemical properties of the new carbon based nanostructures that can be used in nanodevices. Recent publications showed that using sulfur or phosphorus atoms [6][7][8]12,13] it is possible to open a band gap in the band structure of graphene. For example, we found that a band gap of 0.30 eV could be opened when a sulfur atom replaces a carbon atom in a 5 Â 5 graphene supercell [12], whereas a larger band gap was determined for P-doped graphene, even though Al-doped graphene is metallic [13].…”

Chemical Reactivity and Band‐Gap Opening of Graphene Doped with Gallium, Germanium, Arsenic, and Selenium Atoms

“…In contrast, the synthesis of graphene doped with 3 p elements has proven to be more taxing. For example, if Al is used as the dopant, strong structural changes are induced, because Al has an atomic radii that is considerably larger than that of C. [10][11][12][13][14][15] However, despite the larger radii of Si, P, and S, the preparation of Si-doped, [14][15][16][17][18][19] P-doped, [14,15,[20][21][22][23][24][25] and S-doped [14][15][25][26][27][28][29][30][31][32][33] graphene has been reported. The new materials have been characterized by means of theoretical and experimental techniques.…”

Communication: Oscillated band gaps of B/N-codoped α-graphyne

“…17,[22][23][24][25][26][27][28] For example, the band of bilayer graphene is opened when K atoms are adsorbed on grapheneSiC system. 24 This is due to that the SiC acts as hole doping and K atom acts as electron doping.…”