关键词: 石墨烯吸附O原子/
扭转形变/
能带结构/
光学性质
English Abstract
Electron-theoretical study on the influences of torsional deformation on electrical and optical properties of O atom absorbed graphene
Fan Da-Zhi,Liu Gui-Li,
Wei Lin
1.College of Constructional Engineering, Shenyang University of Technology, Shenyang 110870, China
Fund Project:Project supported by the National Natural Science Foundation of China (Grant No. 51371049).Received Date:03 July 2017
Accepted Date:06 September 2017
Published Online:05 December 2017
Abstract:The effects of torsional deformation on the structural stability, the electronic structures and the optical properties, including adsorption energy, band gap, absorption coefficient and reflectivity of O atom adsorbed graphene are studied by using the first-principles calculations. Our results indicate that the C atom closest to O atom is pulled up, causing the graphene plane to be distorted after the O atom has been adsorbed. The adsorption energy calculations show that due to the adsorption of O atom, the structural stability of graphene system decreases, but the degree of torsion has a weak effect on the structural stability. The analysis of band structure shows that the adsorption of O atom causes the graphene to convert into a semiconductor from a metal. Torsional deformation makes it change from a semiconductor to a metal, and to a semiconductor. The O atom adsorption system with a torsion angle of 12° has an indirect band gap but the band gaps of other systems are all direct bandgaps. Compared with the intrinsic graphene torsion system, the adsorbed O atom system has an electronic structure that is less sensitive to torsional deformation. When the torsion angle changes from 10° to 16°, the bandgap is always stable at around 0.11 eV. And the adsorption system always corresponds to a narrow bandgap semiconductor in this torsion angle range. For optical properties, comparing with the O atoms adsorbed on graphene with the 0° torsion angle, the peaks of the absorption coefficient and the reflectivity of the system are reduced, and have a transform of red shift into blue shift in a torsion angle ranging from 2° to 20°.
Keywords: O atom adsorbed on graphene/
torsional deformation/
band structure/
optical properties
