The specific conductivity logσ T and thermal electromotive force coefficient Q T of perovskite-like lanthanum cobaltite were measured over the temperature range 1173 K ≤ T ≤ 1323 K depending on the partial pressure of oxygen (10−8 atm ≤ p O 2 ≤ 1 atm). The p O 2-T-δ phase diagram of solid LaCoO3-δ studied earlier was used to recalculate the electric property data into the log σ T -δ and Q T -δ dependences. The isoconcentration temperature dependences of specific conductivity (logσ)δ-1/T and Seebeck coefficient Q δ-1/T for LaCoO3-δ were analyzed. The conclusion was drawn that charge transfer was activation in character and had a low activation energy. This was evidence that small-radius polarons (Co •Co and Co ′Co ) were responsible for charge transfer in perovskite-like lanthanum cobaltite. The calculated equilibrium constants for the formation of electronic defects and functional dependences of defect concentration [Co •Co ] T = f 1(δ) and [Co ′Co ] T = f 2(δ) were used to analyze polaron transfer parameters in LaCoO3-δ.
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