Yolk–Shell Nanoreactors With Dual Confinement and Catalysis for High‐Performance Lithium−Sulfur Batteries

ABSTRACT The practical application of lithium−sulfur (Li−S) batteries is hindered by the shuttle effect of soluble lithium polysulfides and sluggish sulfur redox kinetics, resulting in rapid capacity fading and limited cycle life. Here, we present a rationally engineered yolk–shell nanoreactor architecture that integrates dual confinement and catalytic functionality to address these challenges. The nanoreactor comprises a polar, catalytically active core encapsulated within a conductive nitrogen‐doped carbon shell, offering synergistic physical restriction of polysulfides and accelerated multistep sulfur conversion. Density functional theory calculations reveal uniformly low‐energy barriers along the Li 2 S 8 ‐to‐Li 2 S pathway, with no evident rate‐limiting step. Benefiting from this cooperative design, the sulfur host achieves a ultralow capacity decay (0.028% per cycle over 1000 cycles at 2 C) and enables a high areal capacity (493 mAh g −1 at 4.3 mg cm −2 sulfur loading) with 76.3% retention after 100 cycles at 0.3 C. This work offers a versatile strategy for constructing catalysis‐integrated sulfur hosts and highlights the potential of yolk–shell nanoreactors in advancing practical Li−S energy storage systems.