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Updated: May 17, 2026
Tuning Oxide Properties by Oxygen Vacancy Control During Growth and Annealing
Published on: June 9, 2023
Theoretical analysis of oxygen vacancies in layered sodium cobaltate, Na(x)CoO(2-δ)
Simone Casolo1, Ole Martin Løvvik, Harald Fjeld
1Dipartimento di Chimica, Università degli Studi di Milano, Milan, Italy. simone.casolo@unimi.it
Abstract:
Sodium cobaltate with high Na content is a promising thermoelectric material. It has recently been reported that oxygen vacancies can alter the material properties, reducing its figure of merit. However, experimental data concerning the oxygen stoichiometry are contradictory. We therefore studied the formation of oxygen vacancies in Na(x)CoO(2) with first principles calculations, focusing on x = 0.75. We show that a very low oxygen vacancy concentration is expected at the temperatures and partial pressures relevant for applications.
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