The synthesis of three layer sodium cobalt oxide, Na xCoO 2 (x=0.3, 0.5, 0.6, 0.75 and 1.0) is reported. For x=0.6, 0.75, and 1.0, conventional solid-state synthesis was employed. x=0.3 and 0.5 were obtained via oxidative deintercalation of sodium at room temperature. x=0.3 can be hydrated to Na 0.3CoO 2•1.3H 2O which is superconducting with a T c of 4.3 K. Although having the same chemical stiochiometry as the previously reported two layer superconductor, it has a different stacking sequence of CoO 2 layers making it structurally distinct. Crystals of three layer NaCoO 2 show triangular morphology compared to hexagonal morphology for two layer Na 0.7CoO 2.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering