1. Novel spherical cobalt/nickel mixed-vanadates as high-capacity anodes in lithium ion batteries.
- Author
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Gong, Feng, Xia, Dawei (David), Zhou, Qiang, Liao, Jiaxuan, and Wu, Mengqiang
- Subjects
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LITHIUM-ion batteries , *X-ray diffraction , *CYCLIC voltammetry - Abstract
Abstract In the past four years, transition metal vanadates have received booming attention as anode materials for lithium ion batteries (LIBs) due to their outstanding specific capacities, decent cycling performance and superior rate properties. Among them, Co 3 V 2 O 8 is the most reported species. However the cobalt is expensive, thus the replacement of cobalt would be a favorable route. So far, mixed vanadates have been rarely reported because of the remarkable difficulty in fabrication, among which cobalt/nickel mixed vanadates are the most attractive. In this work, a facile and green hydrothermal method with organic linker has been developed, to achieve modulated cobalt/nickel mixtures. It was corroborated by the X-ray diffraction (XRD) patterns and cyclic voltammetry (CV) profiles that single phase of cubic Co 3 V 2 O 8 crystal structures were formed. The mixed vanadates demonstrated ultrahigh reversible capacity of over ∼1800 mAh/g at the current density of 0.2 A/g after ∼200 cycles and superb rate capability of ∼600 mAh/g at 4 A/g. The enhanced electrochemical performances of the higher-nickel-ratio indicated their considerable potential as high-capacity anode materials in LIBs. Graphical abstract Image 1 Highlights • Cobalt/nickel mixed vanadates were obtained via one-step and green hydrothermal process. • The mixed vanadates maintain the cubic crystal of Co 3 V 2 O 8 with nickel doping. • Higher concentration of doped nickel induced uniform nanoparticles smaller than 100 nm. • CoNi 2 V 2 O 8 delivered reversible capacity of 1800 mAh/g at 0.2 A/g and 600 mAh/g at 4 A/g. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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