Mo₂C-MoP heterostructure regulate the adsorption energy of electrocatalysts in high-performance Li-S batteries

The cathodic polysulfides electrocatalyst, such as Mo₂C, offers a promising approach to mitigate the shuttling effect by providing strong polysulfide adsorption and catalyst abilities to improve the electrochemical performance of Lithium-sulfur (Li-S) batteries. However, according to the Sabatier principle, excessive adsorption of Mo₂C undermines the conversion of polysulfides. This undesirable effect can be mitigated by forming the heterostructure of Mo₂C-MoP. Even more importantly, the introduction of MoP can prevent the surface gelation of Mo₂C and expose more active sites. Consequently, the Li-S batteries with the Mo₂C-MoP sulfur host exhibit outstanding long-term cycling stability, showcasing a mere 0.035% capacity decay per cycle over 800 cycles at 1 C. This work on the balance between adsorption capacity and catalytic active of cathodic polysulfides electrocatalyst provides a new vision for realizing a high-performance Li-S batteries.