Identification of an unconventional zinc coordination site in anhydrous Zn{sub x}V{sub 2}O{sub 5} aerogels from X-ray absorption spectroscopy

Journal Article · Sun Aug 01 04:00:00 EDT 1999 · Chemistry of Materials

DOI:https://doi.org/10.1021/cm990225c· OSTI ID:696626

Giorgetti, M; Passerini, S; Smyrl, W H ^[1]; Berrettoni, M ^[2]

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1. Univ. of Minnesota, Minneapolis, MN (United States). Dept. of Chemical Engineering and Materials Science
2. Univ. di Bologna (Italy). Dipt. di Chimica Fisica ed Inorganica

V{sub 2}O{sub 5} aerogel (ARG) has been studied as an insertion host for lithium ions and for several polyvalent cations. The stability, reversibility, and capacity for ion insertion and release processes make the amorphous ARG an interesting material for battery applications. The local structural modifications resulting from the chemical insertion of Zn{sup 2+} ions into the host have been investigated by X-ray absorption spectroscopy (XAS). X-ray absorption near-edge structure (XANES) spectra at the V K-edge of Zn{sub x} V{sub 2}O{sub 5} did not show any substantive change as a function of increasing amounts of intercalated ions, thus indicating the absence of interactions between the intercalated ions and the vanadium ions. To study the structural sites of the polyvalent ions, EXAFS (extended X-ray absorption fine structure) spectra have been recorded at the Zn K-edge. The EXAFS analysis showed that the Zn{sup 2+} ions are 4-fold coordinated by almost coplanar oxygens. In addition, differences in the first shell of the inserted Zn{sup 2+} as a function of the intercalation level have been observed. The first-shell Zn-O bond length shortened and the EXAFS Debye-Waller factor increased. This suggests a decrease of the local geometrical order of the first shell as polyvalent cations are inserted.

• Sponsoring Organization: USDOE, Washington, DC (United States)
• OSTI ID: 696626
• Journal Information: Chemistry of Materials, Journal Name: Chemistry of Materials Journal Issue: 8 Vol. 11; ISSN CMATEX; ISSN 0897-4756
• Country of Publication: United States
• Language: English

Related Subjects

25 ENERGY STORAGE
36 MATERIALS SCIENCE
CLATHRATES
COORDINATION VALENCES
ELECTRIC BATTERIES
MORPHOLOGICAL CHANGES
STRUCTURAL CHEMICAL ANALYSIS
VANADIUM OXIDES
ZINC