Electronic Structure And Transport Properties Of Graphene Adsorbed By Super-halogen Clusters And Super-alkali Clusters

Because of the special physical properties different from bulk solid materials,nano materials have attracted people’s attention.At present,nano materials have been widely used in various fields of life.While nano materials are convenient for people’s life,it is more urgent to explore their potential applications.With the continuous development of microelectronics technology,the changes brought to people are changing with each passing day.Under the background of the limited development of electronic devices,it is urgent to find a way to replace silicon.In 2004,graphene,a two-dimensional nano material with many excellent physical properties,came into people’s eyes.The disadvantage of graphene is that it lacks band gap,so it limits the application of graphene in the field of electronic devices.In this paper,super halogen clusters and super alkali clusters are used.The dipole field of the clusters opens the band gap of the double-layer graphene,and the adsorption of the two clusters makes the armchair graphene nanoribbons（AGNRs）form a PN junction,and both structures have negative differential resistance effect.Firstly,using density functional theory and the first principle of non-equilibrium Green’s function,we study the LiF₂ / BLG / Li₃O sandwich structure and the electronic structure and transport properties of the original bilayer graphene,which is composed of the bilayer graphene（BLG）super halogen LiF₂ cluster and the super alkali Li₃O cluster.It can open the band gap of bilayer graphene,and the space separation of the upper and lower layers of electrons and holes in the system is very suitable for obtaining efficient photoelectric conversion in photovoltaic cells.For LiF₂ / BLG / Li₃O sandwich structure,there is a negative differential resistance effect in the IV curve,and it is also observed that the IV curve is asymmetric under the positive and negative bias.Secondly,we also studied the electronic structure and quantum transport properties of the armchair graphene nanobelts（Li3 / AGNRs/ LiF₂）and the original armchair graphene nanobelts（AGNRs）adsorbed by the super halogen LiF₂ clusters and the super alkali Li3 clusters.The results show that the molecules of the super halogen LiF₂ clusters and the super alkali Li3 clusters can stably adsorb on the agnrs Li3 / AGNRs /LiF₂ structure can reduce the band gap,the conduction voltage and the transmission coefficient of the device,and has the rectifying characteristic of PN junction when the forward bias current is larger than the reverse bias current.The calculation results also show that in a adsorption of different regions of GNRs on super alkali clusters and super halogen clusters is a feasible way for the formation of agnrs with PN junction characteristics.