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Effects of Mn and Ti doping on superconductivity and charge ordering in NaxCoO2 system

Y. G. Shi·H. X. Yang·X. Liu·W. J. Ma·C. J. Nie·W. W. Huang·J. Q. Li
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Abstract

The superconductivity in Na0.3Co1-xMxO2.1.3H2O and the charge ordering in Na0.5Co1-xMxO2 have been investigated for M = Mn and Ti substituting for Co. We have first successfully synthesized the single-phase Na0.7Co1-xMxO2(M= Mn and Ti) materials with 0 < = x < = 0.1, then we obtained Na0.5Co1-xMxO2 (0 < = x < = 0.1, M = Mn and Ti) by Na deintercalation and Na0.3Co1-xMxO2.1.3H2O (0 < = x < = 0.1, M = Mn and Ti) by an additional water intercalations. X-ray diffraction measurements revealed that all samples are single-phase materials, their lattice parameters depend systematically on the Ti and Mn contents. Measurements of physical properties indicate that the superconductivity in Na0.3Co1-xMxO2.1.3H2O is suppressed evidently by Co-site doping and killed at x = 0.02 for Mn doping and x = 0.01 for Ti doping. Charge ordering and magnetic properties in Na0.5Co1-xMxO2 were also influenced by M-atom doping.

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Y. G. Shi, H. X. Yang, X. Liu, W. J. Ma, C. J. Nie, W. W. Huang, J. Q. Li. 2005-01-04. Effects of Mn and Ti doping on superconductivity and charge ordering in NaxCoO2 system. https://doi.org/10.1016/j.physc.2005.08.015

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