Chemical Instability of the Cobalt Oxyhydrate Superconductor under Ambient Conditions

M. L. Foo; R. E. Schaak; V. L. Miller; T. Klimczuk; N. S. Rogado; Yayu Wang; G. C. Lau; C. Craley; H. W. Zandbergen; N. P. Ong; R. J. Cava

doi:10.1016/s0038-1098(03)00334-x

arXiv · cond-mat/0304464

Chemical Instability of the Cobalt Oxyhydrate Superconductor under Ambient Conditions

M. L. Foo·R. E. Schaak·V. L. Miller·T. Klimczuk·N. S. Rogado·Yayu Wang·G. C. Lau·C. Craley·H. W. Zandbergen·N. P. Ong·R. J. Cava

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Abstract

The layered sodium cobalt oxyhydrate superconductor Na0.3CoO2*1.4H2O is shown through X-ray diffraction and thermogravimetric studies to be one of a series of hydrated phases of Na0.3CoO2. Further, it is shown that the material is exceptionally sensitive to both temperature and humidity near ambient conditions, easily dehydrating to a non-superconducting lower hydrate. The observation of this stable lower hydrate with c=13.8 angstroms implies that the superconductivity turns on in this system between CoO2 layer spacings of 6.9 and 9.9 angstroms at nominally constant chemical doping.

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M. L. Foo, R. E. Schaak, V. L. Miller, T. Klimczuk, N. S. Rogado, Yayu Wang, G. C. Lau, C. Craley, H. W. Zandbergen, N. P. Ong, R. J. Cava. 2003-04-21. Chemical Instability of the Cobalt Oxyhydrate Superconductor under Ambient Conditions. https://doi.org/10.1016/s0038-1098(03)00334-x

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