In situ Moessbauer study of redox processes in a composite hydroxide of iron and nickel

Journal Article · Thu Sep 10 04:00:00 EDT 1987 · J. Phys. Chem.; (United States)

DOI:https://doi.org/10.1021/j100303a024· OSTI ID:5954310

Corrigan, D A; Conell, R S; Fierro, C A; Scherson, D A

In situ Moessbauer spectra revealed changes in the electronic and structural properties of Fe sites brought about by redox processes attributed formally to Ni sites in a composite iron/nickel hydroxide. Measurements on the oxidized form, polarized in 1 M KOH at 0.5 V vs. Hg/HgO, revealed a singlet with an isomer shift of 0.22 mm/s vs. ..cap alpha..-Fe. After reduction and polarization at 0.0 V, a doublet with an isomer shift of 0.32 mm/s and a quadrupole splitting of 0.44 mm/s was observed. The spectral changes, which accompanied the formal oxidation of Ni sites at 0.5 V, indicated a partial transfer of electronic density away from trivalent Fe sites and structural rearrangements toward more symmetrical coordination about these sites. This highly oxidized iron species in the composite hydroxide may be involved in the electrocatalytic mechanism for oxygen evolution in alkaline media.

• Research Organization: General Motors Research Labs., Warren, MI
• OSTI ID: 5954310
• Journal Information: J. Phys. Chem.; (United States), Journal Name: J. Phys. Chem.; (United States) Vol. 91:19; ISSN JPCHA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
CATALYSTS
CHEMICAL REACTIONS
DATA
ELECTROCATALYSTS
ELEMENTS
EXPERIMENTAL DATA
HYDROGEN COMPOUNDS
HYDROXIDES
INFORMATION
IRON COMPOUNDS
IRON HYDROXIDES
METALS
MOESSBAUER EFFECT
NICKEL
NICKEL COMPOUNDS
NICKEL HYDROXIDES
NONMETALS
NUMERICAL DATA
OXIDATION
OXYGEN
OXYGEN COMPOUNDS
REDUCTION
TRANSITION ELEMENT COMPOUNDS
TRANSITION ELEMENTS
VOLTAMETRY