Liu Jingjie, Yuan Yifei, Zheng Jianhui, Wang Liguang, Ji Jie, Zhang Qing, Yang Lin, Bai Zhengyu, Lu Jun
Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine Chemicals, School of Chemistry and Chemical Engineering, Henan Normal University, 453007, Xinxiang, Henan, China.
College of Chemistry and Materials Engineering, Wenzhou University, 325035, Wenzhou, Zhejiang, China.
Angew Chem Int Ed Engl. 2023 May 8;62(20):e202302547. doi: 10.1002/anie.202302547. Epub 2023 Apr 12.
Non-equilibrium kinetic intermediates are usually preferentially generated instead of thermodynamic stable phases in the solid-state synthesis of layered oxides. Understanding the inherent complexity between thermodynamics and kinetics is important for designing high cationic ordering cathodes. Single-crystal strategy is an effective way to solve the intrinsic chemo-mechanical problems of Ni-rich cathodes. However, the synthesis of high-performance single-crystal is very challenging. Herein, the kinetic reaction path and the formation mechanism of non-equilibrium intermediates in the synthesis of single-crystal Co-free Ni-rich were explored. We demonstrate that the formation of non-equilibrium intermediate and the electrochemical-thermo-mechanical failure can be effectively inhibited by driving low-temperature topotactic lithiation. This work provides a basis for designing high-performance single-crystal Ni-rich layered oxides by regulating the defective structures.
在层状氧化物的固态合成中，通常优先生成非平衡动力学中间体而非热力学稳定相。理解热力学与动力学之间固有的复杂性对于设计高阳离子有序性阴极至关重要。单晶策略是解决富镍阴极固有化学机械问题的有效方法。然而，高性能单晶的合成极具挑战性。在此，我们探索了单晶无钴富镍合成过程中的动力学反应路径及非平衡中间体的形成机制。我们证明，通过驱动低温拓扑锂化可有效抑制非平衡中间体的形成及电化学 - 热 - 机械失效。这项工作为通过调控缺陷结构设计高性能单晶富镍层状氧化物提供了依据。
