The stability of P2-layered sodium transition metal oxides in ambient atmospheres

Wenhua Zuo; Jimin Qiu; Xiangsi Liu; Fucheng Ren; Haodong Liu; Huajin He; Chong Luo; Jialin Li; Gregorio F Ortiz; Huanan Duan; Jinping Liu; Ming-Sheng Wang; Yangxing Li; Riqiang Fu; Yong Yang

doi:10.1038/s41467-020-17290-6

The stability of P2-layered sodium transition metal oxides in ambient atmospheres

Nat Commun. 2020 Jul 15;11(1):3544. doi: 10.1038/s41467-020-17290-6.

Authors

Wenhua Zuo¹, Jimin Qiu¹, Xiangsi Liu¹, Fucheng Ren², Haodong Liu³, Huajin He¹, Chong Luo⁴, Jialin Li¹, Gregorio F Ortiz^{1

5}, Huanan Duan⁶, Jinping Liu⁷, Ming-Sheng Wang⁴, Yangxing Li⁸, Riqiang Fu⁹, Yong Yang^{10

11}

Affiliations

¹ State Key Laboratory for Physical Chemistry of Solid Surfaces, and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, 361005, Xiamen, People's Republic of China.
² School of Energy Research, Xiamen University, 361005, Xiamen, People's Republic of China.
³ Department of NanoEngineering, University of California San Diego, La Jolla, CA, 92093, USA.
⁴ Department of Materials Science and Engineering, College of Materials, Xiamen University, Xiamen, 361005, Fujian, People's Republic of China.
⁵ Departamento de Química Inorgánica e Ingeniería Química, Instituto Universitario de Investigación en Química Fina y Nanoquímica, Universidad de Córdoba, Campus de Rabanales, Edificio Marie Curie, E-14071, Córdoba, Spain.
⁶ State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, 200240, Shanghai, P. R. China.
⁷ School of Chemistry, Chemical Engineering and Life Science and State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, 430070, Wuhan, Hubei, People's Republic of China. liujp@whut.edu.cn.
⁸ , 4135 Belle Meade Circle, 28012, Belmont, North Carolina, USA.
⁹ National High Magnetic Field Laboratory, 1800 E. Paul Dirac Drive, Tallahassee, FL, 32310, USA.
¹⁰ State Key Laboratory for Physical Chemistry of Solid Surfaces, and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, 361005, Xiamen, People's Republic of China. yyang@xmu.edu.cn.
¹¹ School of Energy Research, Xiamen University, 361005, Xiamen, People's Republic of China. yyang@xmu.edu.cn.

Abstract

Air-stability is one of the most important considerations for the practical application of electrode materials in energy-harvesting/storage devices, ranging from solar cells to rechargeable batteries. The promising P2-layered sodium transition metal oxides (P2-Na_xTmO₂) often suffer from structural/chemical transformations when contacted with moist air. However, these elaborate transitions and the evaluation rules towards air-stable P2-Na_xTmO₂ have not yet been clearly elucidated. Herein, taking P2-Na_0.67MnO₂ and P2-Na_0.67Ni_0.33Mn_0.67O₂ as key examples, we unveil the comprehensive structural/chemical degradation mechanisms of P2-Na_xTmO₂ in different ambient atmospheres by using various microscopic/spectroscopic characterizations and first-principle calculations. The extent of bulk structural/chemical transformation of P2-Na_xTmO₂ is determined by the amount of extracted Na⁺, which is mainly compensated by Na⁺/H⁺ exchange. By expanding our study to a series of Mn-based oxides, we reveal that the air-stability of P2-Na_xTmO₂ is highly related to their oxidation features in the first charge process and further propose a practical evaluating rule associated with redox couples for air-stable Na_xTmO₂ cathodes.

Grants and funding

21761132030, 21935009, 51972257/National Natural Science Foundation of China (National Science Foundation of China)