In situ X-ray absorption fine structure studies of foreign metal ions in nickel hydrous oxide electrodes in alkaline electrolytes

Journal Article · Thu Oct 06 04:00:00 EDT 1994 · Journal of Physical Chemistry; (United States)

DOI:https://doi.org/10.1021/j100091a049· OSTI ID:7070767

Kim, Sunghyun; Tryk, D A; Scherson, D ^[1]; Antonio, M R ^[2]; Carr, R ^[3]

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1. Case Western Reserve Univ., Cleveland, OH (United States)
2. Argonne National Lab., IL (United States)
3. Stanford Synchrotron Radiation Lab., CA (United States)

Aspects of the structural and electronic properties of hydrous oxide films of composite (9:1) Ni/Co and (9:1) Ni/Fe, prepared by electrodeposition, have been examined in alkaline electrolytes using in situ X-ray absorption fine structure (XAFS). An analysis of the X-ray absorption near the edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) for the Co and Fe K-edges of these composite hydrous oxides revealed that, regardless of the oxidation state of nickel sites in the films, the guest metal ions are present as Co[sup 3+] and Fe[sup 3+] and that the cobalt-oxygen distance d(Co-O) = 1.9 [+-] 0.02 [angstrom] and d(Fe-O) = 1.92 [+-] 0.02 [angstrom]. The latter values are in excellent agreement with d(Me-O) (Me = Co or Fe) in CoOOH and [beta]- and [gamma]-FeOOH, respectively, determined by conventional X-ray diffraction. Two clearly defined Me-Ni first coordination shells could be observed in the Fourier transforms (FT) of the K-edge EXAFS of the guest metal recorded at a potential at which both Ni[sup 2+] and Ni[sup 3+] sites are expected to be present. 28 refs., 10 figs., 3 tabs.

• OSTI ID: 7070767
• Journal Information: Journal of Physical Chemistry; (United States), Journal Name: Journal of Physical Chemistry; (United States) Vol. 98:40; ISSN JPCHAX; ISSN 0022-3654
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360104 -- Metals & Alloys-- Physical Properties
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
400400 -- Electrochemistry
CHALCOGENIDES
CHARGED PARTICLES
CHEMISTRY
COBALT IONS
COHERENT SCATTERING
COMPILED DATA
COMPOSITE MATERIALS
DATA
DEPOSITION
DIFFRACTION
ELECTROCHEMISTRY
ELECTRODEPOSITION
ELECTRODES
ELECTROLYSIS
ELECTROLYTES
FILMS
HYDROGEN COMPOUNDS
INFORMATION
IONS
IRON IONS
LYSIS
MATERIALS
NICKEL COMPOUNDS
NICKEL OXIDES
NUMERICAL DATA
OXIDES
OXYGEN COMPOUNDS
SCATTERING
SURFACE COATING
TRANSITION ELEMENT COMPOUNDS
VOLTAMETRY
WATER
X-RAY DIFFRACTION