Layered-to-Tunnel Transformation Enabled by Coordination Bond Reorganization in Oxide Cathodes for Sodium–Ion Batteries

作者：Kang Chen, Qilin Zheng, Min Wen, Wei Yuan, Junjie Liao, Fusheng Zhou, Zhen Qiu, Suyun Wang, Lili Wang, Lituo Zheng, Yiyin Huang, Jiaxin Li, Hurong Yao · 发表于：ACS Applied Materials & Interfaces · 年份：2025 · DOI：10.1021/acsami.5c18702 · 被引用次数：2 · 研究领域：Advancements in Battery Materials、Advanced battery technologies research、Advanced Battery Materials and Technologies

Designing composite structures to enhance the performance of manganese-based sodium-ion battery (SIB) cathodes now represents a significant research focus. However, the development of composite-phase cathodes is hindered by an incomplete understanding of their structural transformation mechanisms. Herein, we elucidate the relationship between the transition metal bond energy and material structure, proposing a coordination bond reorganization strategy to drive structural transformations. This concept is demonstrated using the cathode material Na 0.63 Mn 1– x Ti x O 2, showing that the bond energy of transition metals plays a critical role in the structural transformation process. By introducing stronger Ti–O covalent bonds, we achieved the transition from a layered to tunnel structure. Furthermore, the layered-tunnel intergrowth structure Na 0.63 Mn 0.95 Ti 0.05 O 2 demonstrates a remarkable specific capacity of 194.68 mAh g –1 alongside excellent stability while exhibiting good compatibility with hard carbon anodes. This work validates the feasibility of coordination bond reorganization as a mechanism for autonomous structural transformations, offering new insights for the precise design of high-energy-density materials for next-generation SIBs.