Metallic penta-Graphene/penta-BN2 heterostructure with high specific capacity: A novel application platform for Li/Na-ion batteries

Abstract

Considerable efforts have been devoted to design effective anode material for metal-ion batteries. Heterostructures obtained by vertically stacking two-dimensional (2D) monolayers are being considered as alternatives. Here, a hybrid Van der Waals heterostructure with penta-graphene and penta-BN2 (PG/P-BN2) has been investigated for application as an anode material. First-principles calculations indicate that the PG/P-BN2 heterostructure is energetically and thermally stable. The electronic structures of the pristine and ionized heterostructures suggest their metallic properties, which presages good electrical conductivity for the anode material. The metal ions (Li and Na) are found to have low diffusion barriers and low average open-circuit voltages on the PG/P-BN2 heterostructure. The theoretical specific capacities of the PG/P-BN2 heterostructure for the both metal ions reach up to 1054.35 mA·h·g−1, being superior to those of the previously reported 2D anode materials. These results provide innovative advantages at the complex 2D heterostructures and will propel further development of efficient anode materials for superior alkali metal-ion batteries.