Layered sodium all-Mn-based oxide materials are confronted with irreversible dynamic structural degradation induced by MnO6 layers gliding and Jahn-Teller (J-T) distortion of high-spin Mn3+ during cycling. Although conventional strategies often focus primarily on reducing Mn3+ content in the pristine material, we reveal that such static valence control is insufficient to ensure long-term structural integrity. Instead, we demonstrate that dynamic structural regulation effectively decouples the Mn oxidation state changes from degradation pathways. By designing a P'2-type Na0.64Zn0.07Mn0.92Cu0.08O2 (NZMCO) cathode, which maintains the same initial Mn oxidation state as Na0.67MnO2 (NMO), we achieve exceptional cycling stability via a hierarchical damping-like mechanism. The designed framework integrates two synergistic stabilization pathways: (i) intralayer coordination tuning by counterbalancing Mn─O bond anisotropy, and (ii) interlayer electrostatic shielding to alleviate gliding between adjacent MnO6 layers. This strategic configuration effectively alleviates lattice strain and stress accumulation, suppresses microcrack formation, and significantly reduces transition metal dissolution. Consequently, NZMCO delivers a high specific capacity of 194.95 mAh g-1 at 20 mA g-1, retaining 87.53% of its initial capacity after 1500 cycles at 2000 mA g-1. This work shifts the design paradigm from static Mn valence engineering toward dynamic structural adaptation, offering a sustainable pathway for all-Mn-based layered cathodes.
Chen et al. (2026) studied this question.