Anchoring ability and catalytic activity of B2C2 monolayer as the lithium-sulfur batteries cathode materials: A first principle calculation

Abstract

Through first-principles calculation, the performance of B₂C₂ monolayer as the Li-S batteries cathode anchoring material is systematically investigated. The B₂C₂ monolayer exhibits excellent thermodynamic, kinetic and mechanical stability, which are helpful to resist the volume change caused by the reaction during charging and discharging process. Importantly, the adsorption energy of S₈ clusters and LiPSs in the B₂C₂ monolayer is remarkably higher than that in the cathode electrolyte, which greatly inhibits the generation of shuttle effect. The calculations of the catalytic performance of B₂C₂ monolayer further suggest that the system possesses a lower the Gibbs free energy (ΔG) barrier of 0.71 eV and a fast kinetic conversion process with low diffusion barrier of 0.257 eV along hexatomic ring B₂C₄, implying a fast charge and discharge rate and excellent cycle performance. The B₂C₂ monolayer with high energy conversion efficiency and catalytic activity can be expected as an emerging sustainable clean energy source.