Chemical Instability of the Cobalt Oxyhydrate Superconductor under Ambient Conditions

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.

arXiv comment10 pages and 4 figures

Cited by in corpus (37)

• Superconductivity Phase Diagram of Na(x)CoO(2).1.3H(2)O
• Fermi surface and quasiparticle dynamics of Na(x)CoO2 {x=0.7} investigated by Angle-Resolved Photoemission Spectroscopy
• Charge Disproportionation and Spin Ordering Tendencies in Na(x)CoO2
• Crystal Structure of the Sodium Cobaltate Deuterate Superconductor NaxCoO2o4xD2O (x=1/3)
• Thermodynamic and Transport Measurements on Superconducting Na_xCoO_2 + yH_2O Single Crystals Prepared by Electrochemical De-intercalation
• Structure and Dynamics of Superconducting NaxCoO(2) Hydrate and Its Unhydrated Analog
• Observation of Bulk Superconductivity in NaxCoO2.yH2O and NaxCoO2.yD2O Powder and Single Crystals
• Possible effects of charge frustration in Na${}_x$CoO${}_2$: bandwidth suppression, charge orders and resurrected RVB superconductivity
• Transport and Magnetic Studies on the Spin State Transition of Pr1-xCaxCoO3 up to High Pressure
• The crystal growth and characterization of NaxCoO2 and NaxCoO2yH2O
• A critical assessment of the pairing symmetry in NaxCoO2.yH2O
• Revised superconducting phase diagram of hole doped Na${}_x$(H${}_3$O)${}_z$CoO${}_2\cdot y$H${}_2$O
• Magnetic susceptibility study of hydrated and non-hydrated NaxCoO2-yH2O single crystals
• Raman spectroscopy study of NaxCoO2 and superconducting NaxCoO2.yH2O
• Anomalous electronic Raman scattering in Na_xCoO_2 H_2O
• Impurity Effects on the Superconducting Transition Temperature of NazCoO2.yH2O
• Superconductivity in a layered cobalt oxyhydrate Na${}_{0.31}$CoO${}_2\cdot$1.3H${}_2$O
• Thermodynamic properties in the normal and superconducting states of Na(x)CoO(2)*yH(2)O powder measured by heat capacity experiments
• Specific heat study of the Na(0.3)CoO(2).1.3H(2)O superconductor: influence of the complex chemistry
• Unconventional Superconductivity Induced by Quantum Critical Fluctuations in Hydrate Cobaltate Na${}_x$(H${}_3$O)${}_z$CoO${}_x\cdot$ $y$H${}_2$O -- Relationship between Magnetic Fluctuations and the Superconductivity Revealed by a Co Nuclear Quadrupole Resonance --
• Effect of Na content and hydration on the excitation spectrum of the cobaltite Na_xCoO_2 yH_2O
• Formation of charge and spin ordering in strongly correlated electron systems
• Superconductivity in three-layer Na0.3CoO2*1.3H2O
• A novel route to phase formation of cobalt oxyhydrates using KMnO4 as an oxidizing agent
• Study of intercalation and deintercalation of Na_xCoO_2 yH_2O single crystals
• Synthesis and characterization of Na03RhO206H2O - a semiconductor with a weak ferromagnetic component
• Evidence of large anisotropy in the magnetization of Na0.35CoO2.1.3H2O quasi-single-crystal superconductors
• Water Content and Superconductivity in Na0.3CoO2*yH2O
• Structure and physical properties of NaxCoO2.yH2O superconducting system
• Thermal Expansion and Compressibility in Superconducting NaxCoO2o4xD2O (x?1/3): Evidence for Pressure-Induced Charge Redistribution
• Proton incorporations and superconductivity in a cobalt oxyhydrate
• Superconducting materials - a topical overview
• Superconductivity, charge ordering and structural properties of alpha and beta-NaxCoO2.y(H2O, D2O)
• Influence of water intercalation on the electronic structure of the hydrated Na0.3CoO2.yH2O using a local spin density approximation
• Magnetic anomalies of hydrous cobaltate compound Na_x(H_3O)_zCoO_2 \cdot yH_2O detected by NMR and NQR measurements
• 23Na NMR study of non-superconducting double-layer hydrate NaxCoO2.yH2O
• Effects of Mn and Ti doping on superconductivity and charge ordering in NaxCoO2 system