Facet-Controlled LiMn2O4/C as Deionization Electrode with Enhanced Stability and High Desalination Performance

Yuxin Jiang; Liyuan Chai; Dehe Zhang; Fangping Ouyang; Xiangyuan Zhou; Sikpaam I Alhassan; Sailin Liu; Yingjie He; Lvji Yan; Haiying Wang; Wenchao Zhang

doi:10.1007/s40820-022-00897-3

Facet-Controlled LiMn₂O₄/C as Deionization Electrode with Enhanced Stability and High Desalination Performance

Nanomicro Lett. 2022 Aug 23;14(1):176. doi: 10.1007/s40820-022-00897-3.

Authors

Yuxin Jiang¹, Liyuan Chai^{1

2

3}, Dehe Zhang⁴, Fangping Ouyang^{4

5}, Xiangyuan Zhou¹, Sikpaam I Alhassan¹, Sailin Liu⁶, Yingjie He¹, Lvji Yan¹, Haiying Wang^{7

8

9}, Wenchao Zhang^{10

11

12}

Affiliations

¹ School of Metallurgy and Environment, Central South University, Changsha, 410083, People's Republic of China.
² Chinese National Engineering Research Center for Control and Treatment of Heavy Metal Pollution, Changsha, 410083, People's Republic of China.
³ Water Pollution Control Technology Key Lab of Hunan Province, Changsha, 410083, People's Republic of China.
⁴ School of Physics and Electronics, Hunan Key Laboratory for Super-Microstructure and Ultrafast Process, and Hunan Key Laboratory of Nanophotonics and Devices, Central South University, Changsha, 410083, People's Republic of China.
⁵ State Key Laboratory of Powder Metallurgy, and Powder Metallurgy Research Institute, Central South University, Changsha, 410083, People's Republic of China.
⁶ School of Chemical Engineering and Advanced Materials, Faculty of Sciences, Engineering and Technology, The University of Adelaide, Adelaide, 5005, Australia.
⁷ School of Metallurgy and Environment, Central South University, Changsha, 410083, People's Republic of China. haiyw25@csu.edu.cn.
⁸ Chinese National Engineering Research Center for Control and Treatment of Heavy Metal Pollution, Changsha, 410083, People's Republic of China. haiyw25@csu.edu.cn.
⁹ Water Pollution Control Technology Key Lab of Hunan Province, Changsha, 410083, People's Republic of China. haiyw25@csu.edu.cn.
¹⁰ School of Metallurgy and Environment, Central South University, Changsha, 410083, People's Republic of China. wenchao.zhang@csu.edu.cn.
¹¹ Chinese National Engineering Research Center for Control and Treatment of Heavy Metal Pollution, Changsha, 410083, People's Republic of China. wenchao.zhang@csu.edu.cn.
¹² Water Pollution Control Technology Key Lab of Hunan Province, Changsha, 410083, People's Republic of China. wenchao.zhang@csu.edu.cn.

Abstract

Highlights:

First report of a lithium-ion battery cathode as a deionization electrode for desalination.
A novel approach to suppress manganese dissolution by exposing the (111) facet is proposed.
Excellent desalination performance by the LiMn₂O₄/C cathode. The material achieves an ultrahigh desalination capacity of 117.3 mg g⁻¹ at 1.0 V and a longer cycle life (200 cycles without capacity decay) with minor manganese dissolution during the cycling test in 10 mM aqueous LiCl solution.

Abstract: Battery materials as emerging capacitive deionization electrodes for desalination have better salt removal capacities than traditional carbon-based materials. LiMn₂O₄, a widely used cathode material, is difficult to utilize as a deionization electrode due to its structural instability upon cycling and Mn dissolution in aqueous-based electrolytes. Herein, a facile and low-cost ball-milling routine was proposed to prepare a LiMn₂O₄ material with highly exposed (111) facets. The prepared electrode exhibited relatively low dissolution of Mn during cycling, which shows its long cycle stability. In the hybrid capacitive deionization system, the LiMn₂O₄/C electrode delivered a high desalination capacity of 117.3 mg g⁻¹ without obvious capacity decay at a voltage of 1.0 V with a 20 mM initial salt concentration. In addition, the exposed (111) facets significantly alleviated Mn ion dissolution, which also enhanced the structural steadiness.

Supplementary Information: The online version contains supplementary material available at 10.1007/s40820-022-00897-3.

Keywords: Deionization electrode; Desalination; Lithium-ion battery.