First-principles investigation of Boron-doped graphene/MoS2 heterostructure as a potential anode material for Mg-ion battery

Abstract

In this work, the potential of boron-doped graphene/MoS2 (Gr/MoS2) as an anode material for magnesium ion batteries was investigated using density functional theory (DFT) based on first-principles calculations. It’s found that the adsorption capacity gradually increases (−3.078 eV) with the increase in the number of doped-boron atom. Due to the lower electronegativity of boron atom (2.04) compared to carbon atom (2.55), electrons can be transferred from boron atom to neighboring carbon atoms, resulting in positively charged boron atom. Boron doping introduces p-type doping, which increases the number of holes in the substrate and raises the carrier concentration. The energy of the density of states near the Fermi level also increases with the increase of boron-doping concentration, indicating its excellent electronic conductivity. When the number of boron atoms reaches four, the barriers of the two diffusion paths reduce to 0.49 eV and 1.025 eV, respectively. Simultaneously, the theoretical magnesium storage capacity increases to 147.26 mAh g−1. Our research results demonstrate that boron-doping significantly enhances the adsorption and storage performance of Mg, providing a theoretical basis for the investigation of anode materials for magnesium ion batteries.