Hydrogen passivated [formula omitted]-borophene nanoribbon: A propitious one-dimensional metallic anode for sodium-ion rechargeable batteries

Abstract

Synthesized borophene nanoribbons are the single-atom-thick self-assembly of light weight boron atoms separated by hexagonal hole arrays. In this current study, van der Waals corrected density functional theory have been employed to inspect the interaction of Na with both edge hydrogen passivated β12-borophene nanoribbon, based upon first-principles calculations. It is found that the six member ring site is favorable location for Na insertion. Gradual decrease in adsorption energies is observed with increasing Na concentration owing to the fact that the number of vacant sites on anchoring nanoribbon decreases and metal–metal electrostatic repulsion increases. The chemical stoichiometry of full sodiated nanoribbon corresponds to B11H2Na7 with a maximum gravimetric capacity of 1551.65 mAhg−1 without the sacrifice of Na mobility (diffusion barrier of 0.38 eV). Bader charge investigation reveals that 0.83|e| is transferred from Na atom, implying high electronic conductivity of B33H6 nanoribbon during the adsorption process. The average insertion potential is obtained as 0.66 V versus Na/Na+, lying into 0.1–1 V desirable anode potential range. Our study confirm that β12-borophene nanoribbon holds a great potential to act as a propitious negative electrode material for sodium-ion rechargeable batteries based on its structural, electronic and electrochemical properties.