Wu Zhonghan, Ni Youxuan, Jiang Na, Li Jinhan, Zhou Limin, He Lunhua, Zhang Liang, Zhang Kai, Cheng Fangyi, Chen Jun
State Key Laboratory of Advanced Chemical Power Sources, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Renewable Energy Conversion and Storage Center (RECAST), College of Chemistry, Nankai University, Tianjin, 300071, China.
School of Energy and Power Engineering, Nanjing University of Science and Technology, Nanjing, 210094, China.
Adv Mater. 2025 Jul;37(27):e2419137. doi: 10.1002/adma.202419137. Epub 2025 Apr 22.
High-voltage oxygen anionic redox provides a transformative opportunity to achieve high energy density of batteries. However, it is challenging to guarantee the reversibility of both cationic and anionic redox for layered transition metal (TM) oxide cathode materials due to the high oxygen-redox reactivity and the complex structural rearrangements. Herein, a honeycomb-layered NaNiLiMnO (NNLMO) cathode material with the NiMn and LiMn dual-topology superlattice is proposed for sodium-ion batteries. The theoretical and experimental studies demonstrate that the Ni electronic configuration serves as a redox buffer to tune the cationic and anionic redox activity by enlarging the energy gap between O 2p and Mn 3d orbitals, while the NiMn topology renders the LiMn topology delocalized in the TM layers to reinforce the superstructure stability through suppressing the intralayer Mn migration and O formation. As a result, NNLMO delivers a highly reversible capacity of 224 mAh g with the mitigated voltage hysteresis and exhibits remarkable capacity retention of 92.2% over 50 cycles within the wide voltage range of 1.5-4.5 V. The findings suggest a new insight into the topological superstructure design of high-energy oxide cathode materials for sustainable batteries.
高压氧阴离子氧化还原为实现电池的高能量密度提供了一个变革性的机会。然而，由于高氧氧化还原反应性和复杂的结构重排，对于层状过渡金属（TM）氧化物阴极材料而言，要保证阳离子和阴离子氧化还原的可逆性具有挑战性。在此，提出了一种具有NiMn和LiMn双拓扑超晶格的蜂窝状层状NaNiLiMnO（NNLMO）阴极材料用于钠离子电池。理论和实验研究表明，Ni电子构型作为一种氧化还原缓冲剂，通过扩大O 2p和Mn 3d轨道之间的能隙来调节阳离子和阴离子氧化还原活性，而NiMn拓扑结构使LiMn拓扑结构在TM层中离域，通过抑制层内Mn迁移和O形成来增强超结构稳定性。结果，NNLMO在1.5 - 4.5 V的宽电压范围内提供了224 mAh g的高度可逆容量，同时减轻了电压滞后，并在50次循环中表现出92.2%的显著容量保持率。这些发现为可持续电池的高能量氧化物阴极材料的拓扑超结构设计提供了新的见解。
