Enthalpy of Formation of Point Defects in Nonstoichiometric Oxides

• Autorzy: Stokłosa A.
• Języki publikacji: EN

Abstrakty

EN

The relationship between the enthalpies of point defects formation, Delta Hdef, and cohesive enthalpy, Delta HMa / bO , in metal oxides exhibiting high departure from the stoichiometric composition has been discussed. It was found that the enthalpy of point defects formation during the change of the oxygen activity is strongly correlated with the change of cohesive enthalpy upon in corporation or liberation of oxygen from the crystal. Based on the relationship between the cohesive enthalpy and crystal composition, a new method of determination of enthalpy of point defects formation has been proposed. The obtained results remain in agreement with experimentally observed negative values of Delta Hdef corresponding to the formation of either cation vacancies or defect complexes in Fe1-yO and Mn1-yO, and positive values of enthalpy, Delta HVO , in the case of formation of oxygen vacancies in metal oxides such as M2O3-x and MO2-x.

Słowa kluczowe

EN

metal oxides; point defects; calculation of enthalpy of formation of point defects

• Wydawca: Polskie Towarzystwo Chemiczne
• Czasopismo: Polish Journal of Chemistry
• Rocznik: 2009
• Tom: Vol. 83, nr 8
• Strony: 1455--1462
• Opis fizyczny: Bibliogr. 23 poz., rys.

Twórcy

autor

Stokłosa A.

• Faculty of Chemical Engineering and Technology, Cracow University of Technology, ul. Warszawska 24, 31-155 Kraków, Poland,

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