Atomic layer deposition of Al{sub 2}O{sub 3} on V{sub 2}O{sub 5} xerogel film for enhanced lithium-ion intercalation stability

Journal Article · Sun Jan 15 00:00:00 EST 2012 · Journal of Vacuum Science and Technology. A, International Journal Devoted to Vacuum, Surfaces, and Films

DOI:https://doi.org/10.1116/1.3664115· OSTI ID:22054134

Dawei, Liu; Yanyi, Liu; Candelaria, Stephanie L; Guozhong, Cao; Liu, Jun; Jeong, Yoon-Ha ^[1]

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1. Department of Materials Science and Engineering, University of Washington, Seattle, Washington 98195 (United States)

V{sub 2}O{sub 5} xerogel films were fabricated by casting V{sub 2}O{sub 5} sols onto fluorine-doped tin oxide glass substrates at room temperature. Five, ten and twenty atomic layers of Al{sub 2}O{sub 3} were grown onto as-fabricated films respectively. The bare film and Al{sub 2}O{sub 3}-deposited films all exhibited hydrous V{sub 2}O{sub 5} phase only. Electrochemical impedance spectroscopy study revealed increased surface charge-transfer resistance of V{sub 2}O{sub 5} films as more Al{sub 2}O{sub 3} atomic layers were deposited. Lithium-ion intercalation tests at 600 mAg{sup -1} showed that bare V{sub 2}O{sub 5} xerogel film possessed high initial discharge capacity of 219 mAhg{sup -1} but suffered from severe capacity degradation, i.e., having only 136 mAhg{sup -1} after 50 cycles. After deposition of ten atomic layers of Al{sub 2}O{sub 3}, the initial discharge capacity was 195 mAhg{sup -1} but increased over cycles before stabilizing; after 50 cycles, the discharge capacity was as high as 225 mAhg{sup -1}. The noticeably improved cyclic stability of Al{sub 2}O{sub 3}-deposited V{sub 2}O{sub 5} xerogel film could be attributed to the improved surface chemistry and enhanced mechanical strength. During repeated lithium-ion intercalation/de-intercalation, atomic layers of Al{sub 2}O{sub 3} which were coated onto V{sub 2}O{sub 5} surface could prevent V{sub 2}O{sub 5} electrode dissolution into electrolyte by reducing direct contact between active electrode and electrolyte while at the same time acting as binder to maintain good mechanical contact between nanoparticles inside the film.

• OSTI ID: 22054134
• Journal Information: Journal of Vacuum Science and Technology. A, International Journal Devoted to Vacuum, Surfaces, and Films, Vol. 30, Issue 1; Other Information: (c) 2012 American Vacuum Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 1553-1813
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
36 MATERIALS SCIENCE
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALUMINIUM OXIDES
CASTING
CHARGE EXCHANGE
DEPOSITION
DISSOLUTION
DOPED MATERIALS
ELECTRODES
ELECTROLYTES
FLUORINE
GELS
GLASS
LAYERS
LITHIUM IONS
NANOSTRUCTURES
SOLS
SPECTROSCOPY
SURFACES
TIN OXIDES
VANADIUM OXIDES