Electrochemical intercalation of oxygen in Nd{sub 2}NiO{sub 4+x} (0 {le} x {le} 0.18) at 298 K
- Univ. of Houston, TX (United States)
Electrochemical intercalation of oxygen into Nd{sub 2}NiO{sub 4+x} has been investigated by potential step experiments (5 mV steps, 10 {mu}A cutoff current) in aqueous 1 M KOH at 298 K. Stoichiometric Nd{sub 2}NiO{sub 4} is obtained on the initial reduction of the starting material Nd{sub 2}NiO{sub 4.18}. On reoxidation, a maximum composition of Nd{sub 2}NiO{sub 4.1} is obtained below the potential where oxygen evolution is observed. In the composition range 0.0 {le} x {le} 0.08 intercalation is reversible. The electrochemical data show two-phase behavior in the composition range 0.01 {le} x {le} 0.04 and a single-phase region 0.04 {le} x {le} 0.08. Parallel X-ray diffraction studies show that Nd{sub 2}NiO{sub 4+x} is orthorhombic for 0 {le} x {le} 0.01, tetragonal for 0.04 {le} x {le} 0.08 and orthorhombic at Nd{sub 2}NiO{sub 4.18}. An enthalpy of oxidation of -204 kJ/mol of O{sub 2} was obtained from the electrochemical data in the single-phase region. 37 refs., 6 figs., 1 tab.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 98759
- Journal Information:
- Chemistry of Materials, Journal Name: Chemistry of Materials Journal Issue: 11 Vol. 6; ISSN 0897-4756; ISSN CMATEX
- Country of Publication:
- United States
- Language:
- English
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