Enhanced thermopower upon Ni substitution in Na0.75CoO2

N. Gayathri; A. Bharathi; Y. Hariharan

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Enhanced thermopower upon Ni substitution in Na0.75CoO2

N. Gayathri·A. Bharathi·Y. Hariharan

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Abstract

Thermopower measurements have been carried out on the Ni substituted samples of Na0.75CoO2 in the temperature range 4.2K to 300K. The room temperature TEP increases by 20microV/K even with 1% Ni substitution and systematically increases with increasing Ni content upto 5%. The increase in TEP is accompanied by a decrease in rho, thus increasing the ratio of S^(2)/rho on Ni substitution. At low T, the TEP shows an anomaly in the substituted samples, showing a peak at T ~ 20K.

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N. Gayathri, A. Bharathi, Y. Hariharan. 2005-10-13. Enhanced thermopower upon Ni substitution in Na0.75CoO2. https://arxiv.org/abs/cond-mat/0510342

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