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Li-ion batteries (LIBs) have become a house-hold name in the energy-storage research community in the wake of their noteworthy attributes. With increasing energy demands, the urgency to develop high performance LIBs is also rising rapidly which has compelled the researchers to design and fabricate new high capacity materials. Bearing that in mind, we have investigated a carbon–silicon based anode, i.e. Si-doped γ -Graphyne (SiG) nanolayer for its applicability as LIB electrode. Carbon and Silicon are two complementary choices for anode material due to the reason that the weakness of one is complemented by the other i.e. the extensive volume changes of Si anodes is compensated by the stable carbon matrix and the lower Li affinity of carbon is complemented by large capacities of Si anode. The Density Functional Theory (DFT) based studies reveal that SiG nanolayer has a dynamically and thermally stable structure with reliable mechanical properties. Density of states (DOS) calculation substantiates the good conductivity of the nanolayer. The binding energy of the Li atom (adatom) is −1.33 eV resulting from a charge transfer of 0.88 e from Li to the nanolayer. The SiG anode achieved a specific capacity of 1005.05 mAhg−1 (almost 2.7 times the Graphite anode used in commercial LIBs). Climbing Image-Nudged Elastic Band (CI-NEB) calculations depict an easy migration of the adatoms through the anode with an energy barrier of 0.67 eV having diffusion coefficient (D) as 8.91 × 10−14 cm 2 /s. A low working voltage of 0.44 V is obtained advocating a safe operation and good cyclability. So, the theoretical investigation presents favorable outcomes for Si-doped γ -Graphyne to be applicable as a progressive anode in next-generation LIBs. [Display omitted] • Si-doped γ -Graphyne nanolayer is investigated for application in rechargeable Li-ion battery anode using ab initio calculations. • Mechanically, dynamically, and thermally stable nanosheet holds significant electronic properties. • Interactions between the Li and nanosheet resulted in a high storage capacity of 1005.05 mAhg−1. • Low diffusion barrier of 0.67 eV and adequate diffusion coefficient of 8.9 × 10−14 cm2/s is obtained for Li migration. • Open circuit voltage of 0.44 V advocates safe and reversible operation. [ABSTRACT FROM AUTHOR]

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 β 12 -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 B 11 H 2 Na 7 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 B 33 H 6 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 β 12 -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. [Display omitted] • Borophene nanoribbon is investigated by DFT as anode in Na ion batteries. • Structural, mechanical and thermodynamic stability of the 1d layer has been investigated. • Storage capacity of 1551.65 mAhg-1 assisted with low diffusion barrier of 0.38 eV is obtained. • Average voltage of 0.66 V renders borophene nanoribbon as reversible storage material. [ABSTRACT FROM AUTHOR]