Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5459977 | Journal of Alloys and Compounds | 2017 | 8 Pages |
â¢A new 2D material, borophene, is found to be a promising anode material for SIBs.â¢The maximum theoretical specific capacity of borophene is 596 mAh gâ1 for two sides for .â¢The Na diffusion on BÎ is extremely fast with a 12 meV energy barrier.â¢Borophene exhibits metallic characteristics during the whole sodiation process.
2D Boron is an atomically thin layer of boron with both light weight and metallicity, two kinds of potential structures are proposed, namely, a close-packed triangular B layer(denoted Bâ³ hereafter) and a hexagonal voids or vacancies () in B layer(denoted hereafter) (Evgeni S. et al. Nano Lett. 2012, 12, 2441-2445). Here, we use first-principles calculations to investigate the potential of borophene as an anode material for sodium-ion batteries. It is found that borophene has an adsorption energy to sodium atoms of â1.448 eV for all boron atoms in the plane () and â1.731 eV for BÎ. The fully sodiated phase of borophene is Na0.083B and Na0.1B for BÎ and , respectively, which corresponds to a theoretical specific capacity of 248 mAh gâ1 (496 mAh gâ1 for two sides) for BÎ and 298 mAh gâ1 (596 mAh gâ1 for two sides) for . The energy barrier along the furrow of corrugated borophene is only 12 meV for BÎ, which suggests that sodium diffusion on borophene can be extremely fast for BÎ. In addition, a strong directional anisotropy is observed for sodium diffusion with a 352.5 meV barrier perpendicular to the furrow of BÎ. Finally, both exhibit metallic characteristics during the entire sodiation process, which indicates that the material has excellent electronic conductivity. The findings in this work suggest that as an anode material for sodium-ion batteries, borophene can drastically boost the energy and power density of batteries.
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