Twin-graphene as a Promising Anode Material for Na-Ion\nRechargeable Batteries

Abstract

In this work, using density functional\ntheory, a twin-graphene-based\nanode material is investigated for the use in rechargeable ion batteries\nwith sodium as the intercalating ion. The pristine twin-graphene structure\nyielded two best adsorption sites of its surface where the Na atoms\nare adsorbed in a layer-wise fashion. We report a theoretical capacitance\nof 496.2 mAh/g for Na-adsorbed twin-graphene, which is significantly\nhigher than those of many other carbon allotropies. From NEB calculations,\na low diffusion barrier in twin-graphene suggests good diffusivity,\nand with a moderate value of open-circuit voltage, twin-graphene is\na good choice for applications as an anode material in Na-ion rechargeable\nbatteries.