Oxygen nonstoichiometry and magnetotransport properties of Sr 2(Y1-xCax)Co2O7+δ cobalt oxides

M. Matvejeff; J. Nakamura; H. Yamauchi; M. Karppinen

doi:10.1016/j.matchemphys.2004.01.035

Oxygen nonstoichiometry and magnetotransport properties of Sr ₂(Y_1-xCa_x)Co₂O_7+δ cobalt oxides

M. Matvejeff, J. Nakamura, H. Yamauchi, M. Karppinen^*

^*Corresponding author for this work

Department of Chemistry and Materials Science

Research output: Contribution to journal › Article › Scientific › peer-review

1 Citation (Scopus)

Abstract

Tunability of oxygen nonstoichiometry of the Co-based Ruddlesden-Popper phase, Sr₂(Y_1-xCa_x)Co₂O _7+δ, has been investigated using single-phase samples obtained by means of solid-state synthesis within 0.3≤x≤0.5. With cerimetric titrations and thermogravimetric measurements carried out in O₂ and Ar atmospheres, it is found that wide-range oxygen tuning is possible over the whole range of cation stoichiometry, 0.3≤x≤0.5. The minimum oxygen content corresponds to δ≈-1.2 for all the samples (with 0.3≤x≤0.5), while the maximum amount of oxygen loaded in the structure upon 1atm O ₂ annealing increases as x decreases, reaching δ=-0.52 at x=0.3. The change in oxygen nonstoichiometry is reflected in the magnetic and magnetotransport properties of the phase. A small magnetoresistance effect (up to ∼3.5%) is revealed for the oxygenated samples at low temperatures.

Original language	English
Pages (from-to)	329-333
Number of pages	5
Journal	Materials Chemistry and Physics
Volume	85
Issue number	2-3
DOIs	https://doi.org/10.1016/j.matchemphys.2004.01.035
Publication status	Published - 15 Jun 2004
MoE publication type	A1 Journal article-refereed

Keywords

Chemical analysis
Magnetoresistance
Oxygen nonstoichiometry
Ruddlesden-Popper phase

Access to Document

10.1016/j.matchemphys.2004.01.035

Link to publication in Scopus

Fingerprint Dive into the research topics of 'Oxygen nonstoichiometry and magnetotransport properties of Sr 2(Y1-xCax)Co2O7+δ cobalt oxides'. Together they form a unique fingerprint.

Cite this

@article{060c20adda124bdb8845f982f6c68eed,

title = "Oxygen nonstoichiometry and magnetotransport properties of Sr 2(Y1-xCax)Co2O7+δ cobalt oxides",

abstract = "Tunability of oxygen nonstoichiometry of the Co-based Ruddlesden-Popper phase, Sr2(Y1-xCax)Co2O 7+δ, has been investigated using single-phase samples obtained by means of solid-state synthesis within 0.3≤x≤0.5. With cerimetric titrations and thermogravimetric measurements carried out in O2 and Ar atmospheres, it is found that wide-range oxygen tuning is possible over the whole range of cation stoichiometry, 0.3≤x≤0.5. The minimum oxygen content corresponds to δ≈-1.2 for all the samples (with 0.3≤x≤0.5), while the maximum amount of oxygen loaded in the structure upon 1atm O 2 annealing increases as x decreases, reaching δ=-0.52 at x=0.3. The change in oxygen nonstoichiometry is reflected in the magnetic and magnetotransport properties of the phase. A small magnetoresistance effect (up to ∼3.5%) is revealed for the oxygenated samples at low temperatures.",

keywords = "Chemical analysis, Magnetoresistance, Oxygen nonstoichiometry, Ruddlesden-Popper phase",

author = "M. Matvejeff and J. Nakamura and H. Yamauchi and M. Karppinen",

year = "2004",

month = jun,

day = "15",

doi = "10.1016/j.matchemphys.2004.01.035",

language = "English",

volume = "85",

pages = "329--333",

journal = "Materials Chemistry and Physics",

issn = "0254-0584",

publisher = "Elsevier Science",

number = "2-3",

}

TY - JOUR

T1 - Oxygen nonstoichiometry and magnetotransport properties of Sr 2(Y1-xCax)Co2O7+δ cobalt oxides

AU - Matvejeff, M.

AU - Nakamura, J.

AU - Yamauchi, H.

AU - Karppinen, M.

PY - 2004/6/15

Y1 - 2004/6/15

N2 - Tunability of oxygen nonstoichiometry of the Co-based Ruddlesden-Popper phase, Sr2(Y1-xCax)Co2O 7+δ, has been investigated using single-phase samples obtained by means of solid-state synthesis within 0.3≤x≤0.5. With cerimetric titrations and thermogravimetric measurements carried out in O2 and Ar atmospheres, it is found that wide-range oxygen tuning is possible over the whole range of cation stoichiometry, 0.3≤x≤0.5. The minimum oxygen content corresponds to δ≈-1.2 for all the samples (with 0.3≤x≤0.5), while the maximum amount of oxygen loaded in the structure upon 1atm O 2 annealing increases as x decreases, reaching δ=-0.52 at x=0.3. The change in oxygen nonstoichiometry is reflected in the magnetic and magnetotransport properties of the phase. A small magnetoresistance effect (up to ∼3.5%) is revealed for the oxygenated samples at low temperatures.

AB - Tunability of oxygen nonstoichiometry of the Co-based Ruddlesden-Popper phase, Sr2(Y1-xCax)Co2O 7+δ, has been investigated using single-phase samples obtained by means of solid-state synthesis within 0.3≤x≤0.5. With cerimetric titrations and thermogravimetric measurements carried out in O2 and Ar atmospheres, it is found that wide-range oxygen tuning is possible over the whole range of cation stoichiometry, 0.3≤x≤0.5. The minimum oxygen content corresponds to δ≈-1.2 for all the samples (with 0.3≤x≤0.5), while the maximum amount of oxygen loaded in the structure upon 1atm O 2 annealing increases as x decreases, reaching δ=-0.52 at x=0.3. The change in oxygen nonstoichiometry is reflected in the magnetic and magnetotransport properties of the phase. A small magnetoresistance effect (up to ∼3.5%) is revealed for the oxygenated samples at low temperatures.

KW - Chemical analysis

KW - Magnetoresistance

KW - Oxygen nonstoichiometry

KW - Ruddlesden-Popper phase

UR - http://www.scopus.com/inward/record.url?scp=1942451820&partnerID=8YFLogxK

U2 - 10.1016/j.matchemphys.2004.01.035

DO - 10.1016/j.matchemphys.2004.01.035

M3 - Article

AN - SCOPUS:1942451820

VL - 85

SP - 329

EP - 333

JO - Materials Chemistry and Physics

JF - Materials Chemistry and Physics

SN - 0254-0584

IS - 2-3

ER -