A first-principles study of XP3 (X = Ga, Ge and Sb) monolayers as anchoring and catalytic materials for Lithium-sulfur batteries

The practical application of lithium-sulfur batteries still faces persistent issues, such as shuttle effect, sluggish reaction kinetics and inferior coulombic efficiency. One effective strategy to suppress these issues is development of anchoring materials with multiple functions. In this work, XP3 (X = Ga, Ge and Sb) monolayers are designed, and their anchoring and catalytic performances are explored by first-principles calculation. These monolayers are thermodynamically stable, with GaP3 and SbP3 monolayers exhibit excellent anchoring and catalytic ability simultaneously. Notably, the different interaction strength between Li2S and XP3 monolayers derive from the different arrangements of X and P atoms, which further determine the different migration and decomposition energy barriers of Li2S on their surfaces. Additionally, the SbP3 monolayer has a lower Li ion migration barrier compared to other two-dimensional materials, demonstrating superior performance in promoting charging process of lithium sulfur-batteries. This study provides a new vision for designing multi-functional anchoring materials, which can both improve electrode lifespan and charge/discharge rate of lithium sulfur-batteries.