Electrical and Thermoelectric Properties of NaAlO₂

¹Shivendu Tripathi and ²Subodh Kumar Sharma

¹Satish Chandra College, Ballia, U.P., India.

²S. S. V. College, Hapur, U.P., India.

The electrical conductivity (σ) with ionic (σ_i) and electronic (σ_e) conductivity and thermoelectric power (S) of NaAlO₂ have been separated over the entire temperature range from 450K to just below its melting point with the help of time dependent study of dc electrical conductivity. Superionic phase has been observed well below the melting point in which the conductivity is almost purely ionic. The phase transition temperature below which the solid transform from superionic to normal phase has been obtained from electrical conductivity (σ) and thermoelectric power (S) measurement. In normal ionic phase, the solid NaAlO₂ shows mixed conduction (ionic and electronic) behavior. The variation of σ_i and σ_e with temperatures has been shown in various plots and the conduction mechanism is explained by extended lattice gas model.

Keywords: Ionic conductivity; Electronic conductivity; Thermoelectric power, Phase Transition temperature.

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