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Journal of Advanced Ceramics 2022, 11(1): 158-171 https://doi.org/10.1007/s40145-021-0524-8
Research Article | Open Access | Issue | Published: 10 November 2021

Novel P2-type layered medium-entropy ceramics oxide as cathode material for sodium-ion batteries

Show Author's Information Shengxue YAN1,2,  Shaohua LUO1,2,3,4( ),  Liu YANG1,2,  Jian FENG1,2,  Pengwei LI1,2,  Qing WANG1,3,  Yahui ZHANG1,2,3,  Xin LIU1,2,3
School of Materials Science and Engineering, Northeastern University, Shenyang 110819, China
Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province, School of Resources and Materials, Northeastern University at Qinhuangdao, Qinhuangdao 066004, China
School of Resources and Materials, Northeastern University at Qinhuangdao, Qinhuangdao 066004, China
State Key Laboratory of Rolling and Automation, Northeastern University, Shenyang 110819, China
Keywords:
electrochemical performance, cathode materials, medium-entropy oxide (MEO), configuration entropy, sodium-ion batteries (SIBs)
Cite this article:
YAN S, LUO S, YANG L, et al. Novel P2-type layered medium-entropy ceramics oxide as cathode material for sodium-ion batteries. Journal of Advanced Ceramics, 2022, 11(1): 158-171. https://doi.org/10.1007/s40145-021-0524-8
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Abstract Full text Electronic supplementary material About this article

High-entropy oxides (HEOs) and medium-entropy oxides (MEOs) are new types of single-phase solid solution materials. MEOs have rarely been reported as positive electrode material for sodium-ion batteries (SIBs). In this study, we first proposed the concept of the application of MEOs in SIBs. P2-type 3-cation oxide Na2/3Ni1/3Mn1/3Fe1/3O2 (NaNMF) and 4-cation oxide Na2/3Ni1/3Mn1/3Fe1/3-xAlxO2 (NaNMFA) were prepared using the solid-state method, rather than the doping technology. In addition, the importance of the concept of entropy stabilization in material performance and battery cycling was demonstrated by testing 3-cation (NaNMF) and 4-cation (NaNMFA) oxides in the same system. Thus, NaNMFA can provide a reversible capacity of about 125.6 mAh·g-1 in the voltage range of 2-4.2 V, and has enhanced cycle stability. The capacity and decay law of the MEO batteries indicate that the configurational entropy (1.28 R (NaNMFA) > 1.10 R (NaNMF)) of the cationic system, is the main factor affecting the structural and cycle stability of the electrode material. This work emphasizes that the rational design of MEOs with novel structures and different electrochemically active elements may be the strategy for exploring high-performance SIB cathode materials in next-generation energy storage devices.


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About this article

Novel P2-type layered medium-entropy ceramics oxide as cathode material for sodium-ion batteries

Show Author's information Shengxue YAN1,2, Shaohua LUO1,2,3,4( ), Liu YANG1,2, Jian FENG1,2, Pengwei LI1,2, Qing WANG1,3, Yahui ZHANG1,2,3, Xin LIU1,2,3
School of Materials Science and Engineering, Northeastern University, Shenyang 110819, China
Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province, School of Resources and Materials, Northeastern University at Qinhuangdao, Qinhuangdao 066004, China
School of Resources and Materials, Northeastern University at Qinhuangdao, Qinhuangdao 066004, China
State Key Laboratory of Rolling and Automation, Northeastern University, Shenyang 110819, China

Abstract

High-entropy oxides (HEOs) and medium-entropy oxides (MEOs) are new types of single-phase solid solution materials. MEOs have rarely been reported as positive electrode material for sodium-ion batteries (SIBs). In this study, we first proposed the concept of the application of MEOs in SIBs. P2-type 3-cation oxide Na2/3Ni1/3Mn1/3Fe1/3O2 (NaNMF) and 4-cation oxide Na2/3Ni1/3Mn1/3Fe1/3-xAlxO2 (NaNMFA) were prepared using the solid-state method, rather than the doping technology. In addition, the importance of the concept of entropy stabilization in material performance and battery cycling was demonstrated by testing 3-cation (NaNMF) and 4-cation (NaNMFA) oxides in the same system. Thus, NaNMFA can provide a reversible capacity of about 125.6 mAh·g-1 in the voltage range of 2-4.2 V, and has enhanced cycle stability. The capacity and decay law of the MEO batteries indicate that the configurational entropy (1.28 R (NaNMFA) > 1.10 R (NaNMF)) of the cationic system, is the main factor affecting the structural and cycle stability of the electrode material. This work emphasizes that the rational design of MEOs with novel structures and different electrochemically active elements may be the strategy for exploring high-performance SIB cathode materials in next-generation energy storage devices.

Keywords: electrochemical performance, cathode materials, medium-entropy oxide (MEO), configuration entropy, sodium-ion batteries (SIBs)

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Publication history

Received: 15 April 2021
Revised: 30 July 2021
Accepted: 25 August 2021
Published: 10 November 2021
Issue date: January 2022

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© The Author(s) 2021.

Acknowledgements

This work was financially supported by the National Natural Science Foundation of China (Nos. 51674068, 51874079, 51804035, and 11775226), the Natural Science Foundation of Hebei Province (No. E2018501091), the Hebei Province Key Research and Development Plan Project (No. 19211302D), the Fundamental Research Funds for the Central Universities (Nos. N172302001, N182306001, N182312007, N182304018, and N2023040), and the Research Project on the Distribution of Heavy Metals in Soil and Comprehensive Utilization Technology of Tailings in Typical Iron Tailing Reservoir Areas of Hebei Province (No. 802060671901).

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