Balancing Adsorption and Catalysis via Interfacial Electronic Coupling for High‐Performance Room‐Temperature Na‐S Batteries

Room‐temperature sodium‐sulfur (RT Na‐S) batteries face critical challenges from polysulfide shuttling effects and sluggish redox kinetics, requiring an optimal balance between adsorption and catalysis as dictated by the Sabatier principle. Herein, we designed a carbon‐supported ruthenium (C‐Ru) structure with interfacial electronic coupling to resolve this adsorption‐catalysis conundrum. Comprehensive density functional theory (DFT) calculations were first conducted to investigate the atomic‐level impact of the C‐Ru composite on polysulfide conversion. The substantial charge transfer from Ru to carbon optimally tunes polysulfide adsorption, facilitating sulfur redox kinetics while dramatically lowering the Na 2 S decomposition barrier. Geometric and electronic analyses confirm that interfacial charge redistribution systematically weakens Na─S bonds. Guided by these insights, we designed a sponge‐like porous carbon‐Ru nanocomposite as sulfur host (SPC‐Ru) with exceptional electrochemical performance: 924.3 mAh g − 1 after 100 cycles at 0.2 A g − 1 and ultralow capacity decay of 0.097% per cycle over 500 cycles at 2 A g − 1 . This work establishes interfacial electronic coupling as an effective strategy to reconcile adsorption‐catalysis conflicts in metal‐sulfur batteries, offering a rational pathway toward high‐energy‐density and long‐lifespan RT Na‐S energy storage systems.