2 citations · 2 across the 7 of their papers we have counts for
7 papers
Oxidation State of Cobalt in the NaxCoO2-d yH2O Superconductor
Maarit Karppinen, Isao Asako, Teruki Motohashi +1
Here we present results of accurate wet-chemical redox analyses, revealing that the oxidation number of cobalt in the newly discovered CoO2-layer superconductor, NaxCoO2 yH2O (x ~…
Kinetics and thermodynamics of the degree of order of the B cations in double-perovskite Sr2FeMoO6
T. Shimada, J. Nakamura, T. Motohashi +2
Here we show that the B-site cation (Fe/Mo) ordering in the double-perovskite magnetoresistor, Sr2FeMoO6, is controlled by either kinetics or thermal equilibrium depending on the t…
The valence state of iron in the Sr2Fe(Mo,W,Ta)O6.0 double-perovskite system: An Fe K-edge and L2,3-edge XANES study
M. Karppinen, H. Yamauchi, Y. Yasukawa +4
Here we employ both Fe K and L2,3 edge x-ray absorption near-edge structure (XANES) spectroscopy techniques to clarify that iron in the B-site ordered double-perovskite halfmetal,…
Sodium and oxygen nonstoichiometry and thermoelectric properties of NaxCoO2+d
T. Motohashi, M. Karppinen, H. Yamauchi
The sodium-cobalt oxide NaxCoO2+d is a promising candidate for thermoelectric applications since it may possess simultaneously large thermoelectric power and low resistivity. It is…
Oxygen Stoichiometry in Co-1212, Co-1222 and Co-1232 of Homologous Series Co-12s2 of Category-B Layered Copper Oxides
Y. Morita, V. P. S. Awana, H. Yamauchi +1
Here results of a systematic study on oxygen stoichiometry are reported for the first three members of the novel CoSr2(Y,Ce)sCu2O5+2s or Co-12s2 homologous series, i.e. Co-1212, Co…
Magnetosuperconductivity in ruthenocuprates RuSr2GdCu2O8(Ru 1212) and RuSr2(Gd0.75Ce0.25)2Cu2O10 (Ru 1222) a critical review
V. P. S. Awana, M. Karppinen, H. Yamauchi
We reviewed our various results on rutheno-cuprate magneto-superconductors RuSr2GdCu2O8(Ru-1212) and RuSr2(Gd0.75Ce0.25)2Cu2O10(Ru-1222). It is observed, that it is difficult to co…