Effect of ruthenium substitution in layered sodium cobaltate Na{sub x}CoO{sub 2}: Synthesis, structural and physical properties

Journal Article · Wed Jul 15 00:00:00 EDT 2009 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2009.04.030· OSTI ID:21370496

Strobel, Pierre ^[1]; Muguerra, Herve ^[1]; Hebert, Sylvie ^[2]; Pachoud, Elise ^[1]; Colin, Claire ^[1]; Julien, Marc-Henri ^[3]

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1. Institut Neel, CNRS, and Universite Joseph Fourier, B.P. 166, 38042 Grenoble, Cedex 9 (France)
2. CRISMAT (UMR CNRS 6508), ENSI-Caen, F-14050 Caen Cedex (France)
3. Laboratoire de Spectrometrie Physique, UMR CNRS 5588 and Universite Joseph Fourier, 38402 Saint Martin d'Heres (France)

Solid-state synthesis of Na{sub 0.71}Co{sub 1-x}Ru{sub x}O{sub 2} compositions shows that ruthenium can be substituted for cobalt in the hexagonal Na{sub 0.71}CoO{sub 2} phase up to x=0.5. The cell expands continuously with increasing ruthenium content. All mixed Co-Ru phases show a Curie-Weiss behaviour with no evidence of magnetic ordering down to 2 K. Unlike the parent phase Na{sub 0.71}CoO{sub 2}, ruthenium-substituted phases are all semiconducting. They exhibit high thermoelectric power, with a maximum of 165 muV/K at 300 K for x=0.3. The Curie constant C and Seebeck coefficient S show a non-monotonic evolution as a function of ruthenium content, demonstrating a remarkable interplay between magnetic properties and thermoelectricity. The presence of ruthenium has a detrimental effect on water intercalation and superconductivity in this system. Applying to Ru-substituted phases the oxidative intercalation of water known to lead to superconductivity in the Na{sub x}CoO{sub 2} system yields a 2-water layer hydrate only for x=0.1, and this phase is not superconducting down to 2 K. - Graphical Abstract: Effect of ruthenium substitution on thermoelectric power in Na{sub 0.71}Co{sub 1-x}Ru{sub x}O{sub 2} (left) and on low-temperature ac susceptibility in hydrated derivative (right).

• OSTI ID: 21370496
• Journal Information: Journal of Solid State Chemistry, Journal Name: Journal of Solid State Chemistry Journal Issue: 7 Vol. 182; ISSN 0022-4596; ISSN JSSCBI
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALKALI METAL COMPOUNDS
CHALCOGENIDES
CHEMICAL REACTIONS
CLATHRATES
COBALT COMPOUNDS
COBALT OXIDES
CRYSTAL LATTICES
CRYSTAL STRUCTURE
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ELECTRICITY
HEXAGONAL LATTICES
HYDRATES
HYDROGEN COMPOUNDS
LAYERS
MAGNETIC PROPERTIES
OXIDATION
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
REFRACTORY METAL COMPOUNDS
RUTHENIUM COMPOUNDS
SODIUM COMPOUNDS
SUPERCONDUCTIVITY
SYNTHESIS
TEMPERATURE RANGE
TEMPERATURE RANGE 0000-0013 K
TEMPERATURE RANGE 0013-0065 K
TEMPERATURE RANGE 0065-0273 K
TEMPERATURE RANGE 0273-0400 K
THERMOELECTRICITY
TRANSITION ELEMENT COMPOUNDS
WATER