Structure and properties of a novel cobaltate La.sub.0.30./sub.CoO.sub.2./sub..

Knížek, Karel; Hejtmánek, Jiří; Maryško, Miroslav; Šantavá, Eva; Jirák, Zdeněk; Buršík, Josef; Kirakci, Kaplan; Beran, Přemysl

doi:https://dx.doi.org/10.1016/j.jssc.2011.06.021

Number of the records: 1

Structure and properties of a novel cobaltate La.sub.0.30./sub.CoO.sub.2./sub..

1.

SYSNO ASEP	0365147
Document Type	J - Journal Article
R&D Document Type	Journal Article
Subsidiary J	Článek ve WOS
Title	Structure and properties of a novel cobaltate La_0.30CoO₂.
Author(s)	Knížek, Karel (FZU-D)_{RID, ORCID} Hejtmánek, Jiří (FZU-D)_{RID, ORCID} Maryško, Miroslav (FZU-D)_RID Šantavá, Eva (FZU-D)_{RID, ORCID} Jirák, Zdeněk (FZU-D)_{RID, ORCID, SAI} Buršík, Josef (UACH-T)_{RID, ORCID, SAI} Kirakci, Kaplan (UACH-T)_{SAI, RID, ORCID} Beran, Přemysl (UJF-V)_{RID, ORCID, SAI}
Source Title	Journal of Solid State Chemistry. - : Elsevier - ISSN 0022-4596 Roč. 184, č. 8 (2011), s. 2231-2237
Number of pages	7 s.
Language	eng - English
Country	US - United States
Keywords	thermoelectric cobaltates ; La_xCoO ; Na_xCoO₂ ; X-ray and neutron diffraction ; LDA calculations
Subject RIV	BM - Solid Matter Physics ; Magnetism
R&D Projects	GA203/09/1036 GA ČR - Czech Science Foundation (CSF)
	GA202/09/0421 GA ČR - Czech Science Foundation (CSF)
CEZ	AV0Z10100521 - FZU-D (2005-2011)
	AV0Z40320502 - UACH-T (2005-2011)
	AV0Z10480505 - UJF-V (2005-2011)
UT WOS	000293802400049
DOI	10.1016/j.jssc.2011.06.021
Annotation	The layered cobaltate La0.30CoO2 was prepared from NaxCoO2 precursor by a solid-state ionic exchange and was characterized by means of X-ray and neutron diffraction,magnetic,thermalandelectric transport measurements.The compound consists of hexagonal sheets of edge-sharing CoO6 octahedra interleaved by lanthanum monolayers.Compared to Na+ in the parent system,the La3+ ions occupy only one-third of available sites,forming a 2 dimensional superstructure.The deviation from the ideal stoichiometry La1/3CoO2 introduces extra hole carriers into the diamagnetic LS Co3+ matrix making the sample Pauli paramagnetic.The temperature dependence of the electrical conductivity in La0.30CoO2 follows Mott´s T-1/3 law up to about 400K,which is in contrast with the standard metallic behavior in the Na+ homolog possessing the same formal doping.The experiments are complemented by electronic structure calculations for La0.30CoO2 and related NaxCoO2 systems.
Workplace	Institute of Physics
Contact	Kristina Potocká, potocka@fzu.cz, Tel.: 220 318 579
Year of Publishing	2012

Number of the records: 1