First-principles Studies Of Black Phosphorus As New Type Anode Material For Lithium Ion Batteries

The first-principles PAW pseudopotential method with the generalized gradient approximation (GGA) based on the density functional theory (DFT) is employed to investigate the following three problems.1,The geometric and electronic structure of the white phosphorus (WP) and red phosphorus (RP) have been studied by first principles calculations. We analyze the degenerate scale of WP's occupied orbitals. The obtained results are in good agreement with molecular orbital theory. Under certain temperature and pressure, RP's quasi-one dimensional structure is evolved from WP through the Molecular Dynamic method. The same to the other references, such quasi-one dimensional structure is rather unstable owing to its higher energy compared with WP.2,A comprehensive and systematic analysis has been done to the atomic and electronic properties of black phosphorus (BP), a potential and new anode material for lithium ion batteries. The interaction among the layers of BP is Van der Waals Keesom Force which takes an important role in the formation of such puckered layer structure. On the other hand, the energy gap of bulk BP (0.19eV) has compared with that of the single layer BP (0.75eV), such difference is originated from the Van der Waals interaction among layers.3,The selective molecular dynamic (SMD) method has been used to study the lithium ion's migration energy barrier in LiP material, the migration energy barriers along different direction have obtained as 0.61 eV,1.45 eV and 0.48 eV.