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Title: Hole doping into Co-12s2 copper oxides with s fluorite-structured layers between CuO{sub 2} planes

Abstract

In this work, the first three members (s=1, 2, 3) of the Co-12s2 homologous series of multi-layered copper oxides are gradually doped with holes through high-pressure oxygenation (HPO). The phases differ from each other only by thickness of the fluorite-structured layer block (Ce,Y,Ca)-[O{sub 2}-(Ce,Y)]{sub s-1}, between two identical CuO{sub 2} planes. High-resolution transmission-electron microscopy (HRTEM) and electron diffraction (ED) analyses together with both synchrotron X-ray and neutron powder diffraction data, reveal that as a consequence of HPO the charge-reservoir CoO{sub 4}-tetrahedra chains get broken and the lattice symmetry of the Co-12s2 phases changes from orthorhombic to tetragonal. Oxygen contents are analyzed for the samples with wet-chemical and thermogravimetric techniques. The valence state of copper in the CuO{sub 2} plane is determined from Cu L-edge X-ray absorption near-edge structure (XANES) spectra to be compared with the values estimated through bond-valence-sum (BVS) calculations from the crystal structure data. The positive charge induced by oxygen loading (or aliovalent Ca{sup II}-for-Y{sup III} substitution in CoSr{sub 2}YCu{sub 2}O{sub 7+{delta}}) is found not to be completely accommodated in the CuO{sub 2} planes but be rather effectively trapped at the charge-reservoir Co atoms. Superconductivity appears in the Co-1212 (CoSr{sub 2}YCu{sub 2}O{sub 7+{delta}}) samples with the copper valencemore » of 2.13 or higher, whereas in the Co-1222 (CoSr{sub 2}(Ce{sub 0.25}Y{sub 0.75}){sub 2}Cu{sub 2}O{sub 9+{delta}}) and Co-1232 (CoSr{sub 2}(Ce{sub 0.67}Y{sub 0.33}){sub 3}Cu{sub 2}O{sub 11+{delta}}) samples Cu valence does not increase high enough to induce superconductivity.« less

Authors:
 [1];  [2];  [1];  [3];  [4];  [4];  [5];  [6];  [1];  [7];  [3];  [1];  [8]
  1. Materials and Structures Laboratory, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8503 (Japan)
  2. (Norway)
  3. National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan)
  4. National Synchrotron Radiation Research Center, Hsinchu, Taiwan, ROC (China)
  5. Department of Chemistry, National Taiwan University, Taipei, Taiwan, ROC (China)
  6. Institute for Energy Technology, N-2027 Kjeller (Norway)
  7. (India)
  8. Materials and Structures Laboratory, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8503 (Japan). E-mail: karppinen@msl.titech.ac.jp
Publication Date:
OSTI Identifier:
20784904
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Solid State Chemistry; Journal Volume: 179; Journal Issue: 3; Other Information: DOI: 10.1016/j.jssc.2005.11.025; PII: S0022-4596(05)00538-4; Copyright (c) 2005 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ABSORPTION SPECTROSCOPY; COPPER OXIDES; DOPED MATERIALS; FLUORITE; HOLES; LAYERS; NEUTRON DIFFRACTION; ORTHORHOMBIC LATTICES; SUPERCONDUCTIVITY; THERMAL GRAVIMETRIC ANALYSIS; TRANSMISSION ELECTRON MICROSCOPY; VALENCE; X-RAY DIFFRACTION; X-RAY SPECTROSCOPY

Citation Formats

Fjellvag, H., Centre for Materials Science and Nanotechnology, University of Oslo, N-0315 Oslo, Morita, Y., Nagai, T., Lee, J.-M., Chen, J.-M., Liu, R.-S., Hauback, B.C., Awana, V.P.S., National Physical Laboratory, Krishnan Matg, New Delhi 12, Matsui, Y., Yamauchi, H., and Karppinen, M. Hole doping into Co-12s2 copper oxides with s fluorite-structured layers between CuO{sub 2} planes. United States: N. p., 2006. Web. doi:10.1016/j.jssc.2005.11.025.
Fjellvag, H., Centre for Materials Science and Nanotechnology, University of Oslo, N-0315 Oslo, Morita, Y., Nagai, T., Lee, J.-M., Chen, J.-M., Liu, R.-S., Hauback, B.C., Awana, V.P.S., National Physical Laboratory, Krishnan Matg, New Delhi 12, Matsui, Y., Yamauchi, H., & Karppinen, M. Hole doping into Co-12s2 copper oxides with s fluorite-structured layers between CuO{sub 2} planes. United States. doi:10.1016/j.jssc.2005.11.025.
Fjellvag, H., Centre for Materials Science and Nanotechnology, University of Oslo, N-0315 Oslo, Morita, Y., Nagai, T., Lee, J.-M., Chen, J.-M., Liu, R.-S., Hauback, B.C., Awana, V.P.S., National Physical Laboratory, Krishnan Matg, New Delhi 12, Matsui, Y., Yamauchi, H., and Karppinen, M. Wed . "Hole doping into Co-12s2 copper oxides with s fluorite-structured layers between CuO{sub 2} planes". United States. doi:10.1016/j.jssc.2005.11.025.
@article{osti_20784904,
title = {Hole doping into Co-12s2 copper oxides with s fluorite-structured layers between CuO{sub 2} planes},
author = {Fjellvag, H. and Centre for Materials Science and Nanotechnology, University of Oslo, N-0315 Oslo and Morita, Y. and Nagai, T. and Lee, J.-M. and Chen, J.-M. and Liu, R.-S. and Hauback, B.C. and Awana, V.P.S. and National Physical Laboratory, Krishnan Matg, New Delhi 12 and Matsui, Y. and Yamauchi, H. and Karppinen, M.},
abstractNote = {In this work, the first three members (s=1, 2, 3) of the Co-12s2 homologous series of multi-layered copper oxides are gradually doped with holes through high-pressure oxygenation (HPO). The phases differ from each other only by thickness of the fluorite-structured layer block (Ce,Y,Ca)-[O{sub 2}-(Ce,Y)]{sub s-1}, between two identical CuO{sub 2} planes. High-resolution transmission-electron microscopy (HRTEM) and electron diffraction (ED) analyses together with both synchrotron X-ray and neutron powder diffraction data, reveal that as a consequence of HPO the charge-reservoir CoO{sub 4}-tetrahedra chains get broken and the lattice symmetry of the Co-12s2 phases changes from orthorhombic to tetragonal. Oxygen contents are analyzed for the samples with wet-chemical and thermogravimetric techniques. The valence state of copper in the CuO{sub 2} plane is determined from Cu L-edge X-ray absorption near-edge structure (XANES) spectra to be compared with the values estimated through bond-valence-sum (BVS) calculations from the crystal structure data. The positive charge induced by oxygen loading (or aliovalent Ca{sup II}-for-Y{sup III} substitution in CoSr{sub 2}YCu{sub 2}O{sub 7+{delta}}) is found not to be completely accommodated in the CuO{sub 2} planes but be rather effectively trapped at the charge-reservoir Co atoms. Superconductivity appears in the Co-1212 (CoSr{sub 2}YCu{sub 2}O{sub 7+{delta}}) samples with the copper valence of 2.13 or higher, whereas in the Co-1222 (CoSr{sub 2}(Ce{sub 0.25}Y{sub 0.75}){sub 2}Cu{sub 2}O{sub 9+{delta}}) and Co-1232 (CoSr{sub 2}(Ce{sub 0.67}Y{sub 0.33}){sub 3}Cu{sub 2}O{sub 11+{delta}}) samples Cu valence does not increase high enough to induce superconductivity.},
doi = {10.1016/j.jssc.2005.11.025},
journal = {Journal of Solid State Chemistry},
number = 3,
volume = 179,
place = {United States},
year = {Wed Mar 15 00:00:00 EST 2006},
month = {Wed Mar 15 00:00:00 EST 2006}
}