Exploring the Superior Anchoring Performance of the Two-Dimensional Nanosheets B2C4P2 and B3C2P3 for Lithium-Sulfur Batteries

Potential anchoring materials in lithium-sulfur batteries help overcome the shuttle effect and achieve long-term cycling stability and high-rate efficiency. The present study investigates the two-dimensional nanosheets B₂C₄P₂ and B₃C₂P₃ by employing density functional theory calculations for their promise as anchoring materials. The nanosheets B₂C₄P₂ and B₃C₂P₃ bind polysulfides with adsorption energies in the range from -2.22 to -0.75 and -2.43 to -0.74 eV, respectively. A significant charge transfer occurs from the polysulfides, varying from -0.74 to -0.02e and -0.55 to -0.02e for B₂C₄P₂ and B₃C₂P₃, respectively. Upon anchoring the polysulfides, the band gap of B₃C₂P₃ reduces, leading to enhanced electrical conductivity of the sulfur cathode. Finally, the calculated barrier energies of B₂C₄P₂ and B₃C₂P₃ for Li₂S indicate fast diffusion of Li when recharged. These enthralling characteristics propose that the nanosheets B₂C₄P₂ and B₃C₂P₃ could reduce the shuttle effect in Li-S batteries and significantly improve their cycle performance, suggesting their promise as anchoring materials.