Tailoring Electronic Structure to Achieve Maximum Utilization of Transition Metal Redox for High-Entropy Na Layered Oxide Cathodes

Feixiang Ding; Haibo Wang; Qinghua Zhang; Lirong Zheng; Hao Guo; Pengfei Yu; Nian Zhang; Qiubo Guo; Fei Xie; Rongbin Dang; Xiaohui Rong; Yaxiang Lu; Ruijuan Xiao; Liquan Chen; Yong-Sheng Hu

doi:10.1021/jacs.3c00879

Tailoring Electronic Structure to Achieve Maximum Utilization of Transition Metal Redox for High-Entropy Na Layered Oxide Cathodes

J Am Chem Soc. 2023 Jun 28;145(25):13592-13602. doi: 10.1021/jacs.3c00879. Epub 2023 Jun 13.

Authors

Feixiang Ding^{1

2}, Haibo Wang¹, Qinghua Zhang¹, Lirong Zheng³, Hao Guo⁴, Pengfei Yu⁵, Nian Zhang⁵, Qiubo Guo¹, Fei Xie^{1

6}, Rongbin Dang¹, Xiaohui Rong^{1

6

7}, Yaxiang Lu^{1

6

2

7}, Ruijuan Xiao^{1

6

2}, Liquan Chen^{1

6

2

7}, Yong-Sheng Hu^{1

6

2

7}

Affiliations

¹ Key Laboratory for Renewable Energy, Beijing Key Laboratory for New Energy Materials and Devices, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
² Huairou Division, Institute of Physics, Chinese Academy of Sciences, Beijing 101400, China.
³ Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China.
⁴ China Institute of Atomic Energy, Beijing 102413, China.
⁵ State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences Shanghai 200050, China.
⁶ College of Materials Science and Optoelectronic Technology, University of Chinese Academy of Sciences, Beijing 100049, China.
⁷ Yangtze River Delta Physics Research Center Co. Ltd, Liyang 213300, China.

PMID: 37312411
DOI: 10.1021/jacs.3c00879

Abstract

Charge compensation from cationic and anionic redox couples accompanying Na⁺ (de)intercalation in layered oxide cathodes contributes to high specific capacity. However, the engagement level of different redox couples remains unclear and their relationship with Na⁺ content is less studied. Here we discover that it is possible to take full advantage of the high-voltage transition metal (TM) redox reaction through low-valence cation substitution to tailor the electronic structure, which involves an increased ratio of Na⁺ content to available charge transfer number of TMs. Taking Na_xCu_0.11Ni_0.11Fe_0.3Mn_0.48O₂ as the example, the Li⁺ substitution increases the ratio to facilitate the high-voltage TM redox activity, and further F-ion substitution decreases the covalency of the TM-O bond to relieve structural changes. As a consequence, the final high-entropy Na_0.95Li_0.07Cu_0.11Ni_0.11Fe_0.3Mn_0.41O_1.97F_0.03 cathode demonstrates ∼29% capacity increase contributed by the high-voltage TMs and exhibits excellent long-term cycling stability due to the improved structural reversibility. This work provides a paradigm for the design of high-energy-density electrodes by simultaneous electronic and crystal structure modulation.