Synergizing Spatial Confinement and Dual‐Metal Catalysis to Boost Sulfur Kinetics in Lithium–Sulfur Batteries

Abstract

AbstractSluggish kinetics and parasitic shuttling reactions severely impede lithium–sulfur (Li–S) battery operation; resolving these issues can enhance the capacity retention and cyclability of Li–S cells. Therefore, an effective strategy featuring core–shell‐structured Co/Ni bimetal‐doped metal–organic framework (MOF)/sulfur nanoparticles is reported herein for addressing these problems; this approach offers unprecedented spatial confinement and abundant catalytic sites by encapsulating sulfur within an ordered architecture. The protective shells exhibit long‐term stability, ion screening, high lithium‐polysulfide adsorption capability, and decent multistep catalytic conversion. Additionally, the delocalized electrons of the MOF endow the cathodes with superior electron/lithium‐ion transfer ability. Via multiple physicochemical and theoretical analysis, the resulting synergistic interactions are proved to significantly promote interfacial charge‐transfer kinetics, facilitate sulfur conversion dynamics, and inhibit shuttling. The assembled Li–S batteries deliver a stable, highly reversible capacity with marginal decay (0.075% per cycle) for 400 cycles at 0.2 C, a pouch‐cell areal capacity of 3.8 mAh cm−2 for 200 cycles under a high sulfur loading, as well as remarkably improved pouch‐cell performance.