Selective Catalysis-Mediated Interface to Stabilize Antimony Atom-Cluster Anode for Robust Potassium-Ion Batteries

Controlling the electrode-electrolyte interfacial behavior is crucial for achieving a high-quality solid electrolyte interphase (SEI) and ensuring sustainable battery performance. Here, we propose a selective catalysis strategy to stabilize antimony atom-cluster (Sb_SA-AC) anode/electrolyte interface for robust potassium-ion batteries (PIBs). Specifically, the electrode featuring Sb_SA-AC in porous carbon (Sb_SA-AC/PC) as “electrocatalyst” unduly catalyzes the reduction of the dimethyl ether-based electrolyte, resulting in loose SEI layer and rapid capacity decay. While in triethyl phosphate-based electrolyte, the Sb_SA-AC/PC selectively catalyzes the preferential decomposition of anions and the polymerization of solvent molecules, leading to a bilayer SEI with inner inorganic-rich components and an outer elastic polyphosphate layer, which improve the interface stability and electrochemical performance. Thus, the Sb_SA-AC/PC maintains a long-term stability over 12 months and demonstrates long-cycling stability over 4000 cycles with a capacity retention of 96%. This research establishes a correlation between electrode/electrolyte interactions and SEI characteristics, providing a new insight for advanced interface engineering in high-performance PIBs and beyond.