Pillaring Effect of K Ion Anchoring for Stable V₂O₅‐Based Zinc‐Ion Battery Cathodes

Abstract Aqueous zinc‐ion batteries (ZIBs) have attracted widespread attention due to their advantages in safety and environmental benignity. However, achieving a cathode material with stable electrochemical performance for such a system remains an ongoing challenge. Herein, a K_0.5V₂O₅ cathode has been designed and synthesized by intercalating of K⁺ into V₂O₅, thus constructing a stable crystal structure by forming chemical bonds between V₂O₅ layers. The successful intercalation of K⁺ has been confirmed by a series of experimental tests and Vienna Ab‐initio Simulation Package simulation. These layer‐interlinking chemical bonds act as “pillars” to strongly hold the V₂O₅ layers together and protect them from dissolution. Furthermore, the K_0.5V₂O₅ electrode also exhibits excellent durability (about 150 mA h g⁻¹ at 5 A g⁻¹ after 3000 cycles). More impressively, even after standing for three days in the solution of 3 M ZnSO₄ electrolyte, the K_0.5V₂O₅ electrode still maintains a high capacity of 92.2 mA h g⁻¹ after 150 cycles, demonstrating its outstanding stability and tolerance in such aqueous electrolyte.