Two-Dimensional Layered Green Phosphorus as an Anode Material for Li-Ion Batteries

Green phosphorus (GP), an allotrope of two-dimensional (2D) layered phosphorus, is considered to be a promising anode material for Li-ion batteries (LIBs) due to its high theoretical specific capacity (2596 mAh/g) based on the formation of Li3P, good flexibility, and high electronic conductivity. In this work, the lithiation mechanism of GP with different layers as anode materials in LIBs is mainly investigated using first-principles calculations. The theoretical calculations indicate that the single-layer (SL) GP shows a higher specific capacity (432.7 mAh/g) than double-layer (DL) and bulk GP (288.4 mAh/g). The Li diffusion in GP is fast with a small energy barrier of 0.14 eV along the zigzag direction. Besides, the average lithiation voltages of SL, DL, and bulk GP are 1.33, 1.35, and 2.07 V, respectively, which exhibit an increasing tendency with the increasing number of GP layers. Additionally, the specific capacity of GP is higher than that of the extensively investigated black phosphorus anode. The obtained results are important for the further investigation of GP as a type of anode material for Li-ion batteries.