Cobalt-Doped FeS2 Nanospheres with Complete Solid Solubility as a High-Performance Anode Material for Sodium-Ion Batteries.
Considering that the high capacity, long-term cycle life, and high-rate capability of anode materials for sodium-ion batteries (SIBs) is a bottleneck currently, a series of Co-doped FeS2 solid solutions with different Co contents were prepared by a facile solvothermal method, and for the first time their Na-storage properties were investigated. The optimized Co0.5 Fe0.5 S2 (Fe0.5) has discharge capacities of 0.220 Ah g(-1) after 5000 cycles at 2 A g(-1) and 0.172 Ah g(-1) even at 20 A g(-1) with compatible ether-based electrolyte in a voltage window of 0.8-2.9 V. The Fe0.5 sample transforms to layered Nax Co0.5 Fe0.5 S2 by initial activation, and the layered structure is maintained during following cycles. The redox reactions of Nax Co0.5 Fe0.5 S2 are dominated by pseudocapacitive behavior, leading to fast Na(+) insertion/extraction and durable cycle life. A Na3 V2 (PO4 )3 /Fe0.5 full cell was assembled, delivering an initial capacity of 0.340 Ah g(-1) .
Department of Energy and Materials Engineering, Dongguk University-Seoul, Seoul, 04620, Republic of Korea.
Kai
K
Zhang
Department of Energy and Materials Engineering, Dongguk University-Seoul, Seoul, 04620, Republic of Korea.
Mihui
M
Park
Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Collaborative Innovation Center of Chemical Science and Engineering, College of Chemistry, Nankai University, Tianjin, 300071, China.
Limin
L
Zhou
Department of Energy and Materials Engineering, Dongguk University-Seoul, Seoul, 04620, Republic of Korea.
Gi-Hyeok
GH
Lee
Department of Energy and Materials Engineering, Dongguk University-Seoul, Seoul, 04620, Republic of Korea.
Jeongyim
J
Shin
Institute for Superconducting and Electronic Materials, University of Wollongong, Wollongong, New South Wales, 2522, Australia.
Zhe
Z
Hu
Institute for Superconducting and Electronic Materials, University of Wollongong, Wollongong, New South Wales, 2522, Australia.
Shu-Lei
SL
Chou
Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Collaborative Innovation Center of Chemical Science and Engineering, College of Chemistry, Nankai University, Tianjin, 300071, China. chenabc@nankai.edu.cn.
Jun
J
Chen
Department of Energy and Materials Engineering, Dongguk University-Seoul, Seoul, 04620, Republic of Korea. dake1234@dongguk.edu.
Yong-Mook
YM
Kang
anode materials; cobalt-doped iron disulfides; sodium-ion batteries; solid solutions