Cr{sub 2}O{sub 5} as new cathode for rechargeable sodium ion batteries

Journal Article · Sat Oct 15 00:00:00 EDT 2016 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/J.JSSC.2016.05.004· OSTI ID:22658060

Feng, Xu-Yong; Chien, Po-Hsiu; Rose, Alyssa M.; Zheng, Jin ^[1]; Hung, Ivan; Gan, Zhehong ^[2]; Hu, Yan-Yan ^[1]

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1. Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL 32306 (United States)
2. Centre of Interdisciplinary Magnetic Resonance, National High Magnetic Field Laboratory, 1800 East Paul Dirac Drive, Tallahassee, FL 32310 (United States)

Chromium oxide, Cr{sub 2}O{sub 5}, was synthesized by pyrolyzing CrO{sub 3} at 350 °C and employed as a new cathode in rechargeable sodium ion batteries. Cr{sub 2}O{sub 5}/Na rechargeable batteries delivered high specific capacities up to 310 mAh/g at a current density of C/16 (or 20 mA/g). High-resolution solid-state {sup 23}Na NMR both qualitatively and quantitatively revealed the reversible intercalation of Na ions into the bulk electrode and participation of Na ions in the formation of the solid-electrolyte interphase largely at low potentials. Amorphization of the electrode structure occurred during the first discharge revealed by both NMR and X-ray diffraction data. CrO{sub 3}-catalyzed electrolyte degradation and loss in electronic conductivity led to gradual capacity fading. The specific capacity stabilized at >120 mAh/g after 50 charge-discharge cycles. Further improvement in electrochemical performance is possible via electrode surface modification, polymer binder incorporation, or designs of new morphologies. - Graphical abstract: Electrochemical profile of a Cr{sub 2}O{sub 5}/Na battery cell and high-resolution solid-state {sup 23}Na MAS NMR spectrum of a Cr{sub 2}O{sub 5} electrode discharged to 2 V. - Highlights: • Cr{sub 2}O{sub 5} was synthesized and used as a new cathode in rechargeable Na ion batteries. • A high capacity of 310 mAh/g and an energy density of 564 Wh/kg were achieved. • High-resolution solid-state {sup 23}Na NMR was employed to follow the reaction mechanisms.

• OSTI ID: 22658060
• Journal Information: Journal of Solid State Chemistry, Journal Name: Journal of Solid State Chemistry Journal Issue: Part 2 Vol. 242; ISSN 0022-4596; ISSN JSSCBI
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
CAPACITY
CATHODES
CHROMATES
CHROMIUM OXIDES
CURRENT DENSITY
ENERGY DENSITY
IONIC CRYSTALS
NMR SPECTRA
NUCLEAR MAGNETIC RESONANCE
REACTION KINETICS
SODIUM IONS
SOLID ELECTROLYTES
SYNTHESIS
X-RAY DIFFRACTION