Manipulating Atomic‐Coupling in Dual‐Cavity Boride Nanoreactor to Achieve Hierarchical Catalytic Engineering for Sulfur Cathode

The catalytic process of Li2S formation is considered a key pathway to enhance the kinetics of lithium‐sulfur batteries. Due to the system‘s complexity, the catalytic behavior is uncertain, posing significant challenges for predicting activity. Herein, we report a novel cascaded dual‐cavity nanoreactor (NiCo−B) by controlling reaction kinetics, providing an opportunity for achieving hierarchical catalytic behavior. Through experimental and theoretical analysis, the multilevel structure can effectively suppress polysulfides dissolution and accelerate sulfur conversion. Furthermore, we differentiate the adsorption (B−S) and catalytic effect (Co−S) in NiCo−B, avoiding catalyst deactivation caused by excessive adsorption. As a result, the as‐prepared battery displays high reversible capacity, even with sulfur loading of 13.2 mg cm−2 (E/S=4 μl mg−1), the areal capacity can reach 18.7 mAh cm−2. The unique cascaded dual‐cavity boride nanoreactor is rationally designed as a sulfur host, which achieves controlled catalysis in the heterogeneous catalytic system of lithium‐sulfur batteries. The coupling between atoms regulates catalyst activity and suppresses Li2S passivation. The mechanism and application investigation of nanoreactor provides a guiding strategy for lithium‐sulfur batteries.