Enhanced thermoelectric properties of Na[sub x]CoO[sub 2] whisker crystals

Peleckis, G.; Motohash, T.; Karppinen, M.; Yamauchi, H.
December 2003
Applied Physics Letters;12/29/2003, Vol. 83 Issue 26, p5416
Academic Journal
Single-crystalline whiskers of thermoelectric cobalt oxide, Na[sub x]CoO[sub 2], have been grown by an unconventional method from potassium-containing compositions, and their transport properties, and chemical compositions were determined. The growth mechanism was analyzed and interpreted by means of thermogravimetric analysis. At 300 K, electrical resistivity ρ, and thermoelectric power S of the whisker are 102 μΩ cm and 83 μV/K, respectively. The power-factor, S[sup 2]/ρ, thus is enhanced up to ∼68 μW/K[sup 2] cm. © 2003 American Institute of Physics.


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