Spatial Confinement in Structural Biomimetic Catalysts: Enhancing Sulfur-Chain Homolysis and Enzyme-like Activity for High-Performance Lithium-Sulfur Batteries.

Our study addresses the critical challenges of sluggish sulfur reaction kinetics and severe lithium polysulfide shuttling in high-energy-density lithium-sulfur batteries under high sulfur loading and lean electrolyte conditions. Inspired by the structure of cytochrome c oxidase, we designed an enzyme-mimetic Fe-TCPP@Cu-BTC catalyst with spatial confinement effects. Its spatially confined configuration induces the homolytic cleavage of Li2S6 to LiS3 and accelerates their subsequent conversion to Li2S. The enzyme-like properties were further evaluated using Michaelis-Menten kinetics, confirming that the homolytic reaction can increase the sulfur conversion rate by nearly 2 orders of magnitude.