Micro-controlling of the grain boundaries in NiCo2O4/NiCo2S4 nanowires for enhanced charge storage

Mengqi Cui; Zining Wang; Hui Wang; Xuyun Wang; Jianwei Ren

doi:10.1039/d1dt02941j

Micro-controlling of the grain boundaries in NiCo₂O₄/NiCo₂S₄ nanowires for enhanced charge storage

Dalton Trans. 2021 Nov 9;50(43):15633-15639. doi: 10.1039/d1dt02941j.

Authors

Mengqi Cui¹, Zining Wang¹, Hui Wang¹, Xuyun Wang¹, Jianwei Ren²

Affiliations

¹ State Key Laboratory Base for Eco-Chemical Engineering, College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao, 266042, China. wangh@qust.edu.cn.
² Department of Mechanical Engineering Science, University of Johannesburg, Cnr Kingsway and University Roads, Auckland Park, 2092, Johannesburg, South Africa.

PMID: 34671791
DOI: 10.1039/d1dt02941j

Abstract

In this work, the micro-controlling of the grain boundaries in NiCo₂O₄/NiCo₂S₄ nanowire arrays was achieved by exposing them to a sulfur containing atmosphere at 300 °C with different exposure times. The results showed that the capacitance of the optimal NiCo₂S₄ sample reached 400 μA h cm^-2 at 30 mA cm^-2 with a current retention rate of 58.6%. The assembled NiCo₂O₄/NiCo₂S₄//activate carbon electrode delivered a capacitance of 299.2 μA h cm^-2 and 241.7 μA h cm^-2 at a current density of 3 mA cm^-2 and 30 mA cm^-2, respectively. The cycling tests showed a good current retention rate of 88.1% after 8000 cycles. Besides, the NiCo₂O₄/NiCo₂S₄ composite exhibited a power density of 480.1 W kg^-1 at an energy density of 47.87 W h kg^-1, and 4773.66 W kg^-1 at 38.67 W h kg^-1, which indicated its potential for practical applications.