Oxygen Edge‐Sharing Strategy in P2‐Type Na0.67MnO2 Cathodes: Synergistic Enhancement of Intercalation Kinetics and Air Stability

Abstract Mn‐based layered oxides have garnered significant attention as cathode materials for energy storage due to their environmental benignity and high theoretical specific capacity. However, practical applications remain constrained by sluggish Na + intercalation kinetics and poor structural stability. In this study, it is engineered that the Mn‐O‐B unit through an oxygen edge‐sharing strategy to modulate Mn─O covalency in P2‐type Na 0.67 MnO 2 , thereby achieving high specific capacity and structural stability. Both experimental results and density functional theory (DFT) calculations reveal that increased TM‐O covalency facilitates Na + diffusion in P2‐type Na 0.67 MnO 2 while simultaneously enhancing air stability. The as‐prepared P2‐type Na 0.67 MnB 0.05 O 2 exhibits a specific capacitance of 452 F g −1 at 1 A g −1 , maintaining 96.75% capacity retention after 8800 cycles. This work elucidates the critical role of oxygen edge‐sharing in optimizing interactions between transition metal and oxygen atoms, establishing a relationship between Mn─O structure and functional properties. These findings advance the development of high‐performance energy storage technologies.