Abstract
We report a simple approach of fabricating thermoelectric γ-NaxCoO2 film with the c-axis orientation using the sol-gel spin-coating method. The inferred sodium content is x = 0.65 according to the correlation between the c-axis lattice constant and x. Temperature dependence of both the resistivity and thermopower resembles that of the γ-Na0.68CoO2 film grown by the reactive solid-phase epitaxy. The fitted thermopower data show that the bandwidth of γ-NaxCoO2 is found to be ~ 101 meV, being close to the quasi-particle band (70-100 meV) derived from an angle-resolved photoemission study of γ-Na0.7CoO2. These results enable the possibility of low-cost fabrication of γ-NaxCoO2-based thermoelectric film devices. Furthermore, we have also topotactically transformed the of γ-NaxCoO2 film to a superconducting Nax(H2O)yCoO2-δ film with Tc, onset = 4.12 K.
Original language | English |
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Pages (from-to) | 91-93 |
Number of pages | 3 |
Journal | Thin Solid Films |
Volume | 518 |
Issue number | 1 |
DOIs | |
Publication status | Published - 2009 Nov 2 |
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Surfaces and Interfaces
- Surfaces, Coatings and Films
- Metals and Alloys
- Materials Chemistry