Oxygen nonstoichiometry, the defect equilibrium model and thermodynamic quantities of the Ruddlesden-Popper oxide Sr3Fe2O7-δ

Yihan Ling, Fang Wang, Riyan Achmad Budiman, Takashi Nakamura, Koji Amezawa

    Research output: Contribution to journalArticlepeer-review

    18 Citations (Scopus)

    Abstract

    Oxygen nonstoichiometry of the Ruddlesden-Popper oxide Sr3Fe2O7-δ was measured at intermediate temperatures (773-1073 K) by coulometric titration and high temperature gravimetry. The oxygen nonstoichiometric behavior was analyzed using the defect equilibrium model with localized electrons. From the defect chemical analysis, estimated oxygen vacancy concentration at the O3 sites increases and at the O1 sites decreases with the increasing temperature. This characteristic behavior is considered to be caused by the redistribution of oxygen and vacancies between the O1 and O3 sites. The obtained thermodynamic quantities of the partial molar enthalpy of oxygen, and the partial molar entropy of oxygen, calculated from the Gibbs-Helmholtz equation are in good agreement with those from the statistical thermodynamic calculation based on the defect equilibrium model, indicating that the proposed defect equilibrium model is reasonable. This journal is

    Original languageEnglish
    Pages (from-to)7489-7497
    Number of pages9
    JournalPhysical Chemistry Chemical Physics
    Volume17
    Issue number11
    DOIs
    Publication statusPublished - 2015

    ASJC Scopus subject areas

    • Physics and Astronomy(all)
    • Physical and Theoretical Chemistry

    Fingerprint Dive into the research topics of 'Oxygen nonstoichiometry, the defect equilibrium model and thermodynamic quantities of the Ruddlesden-Popper oxide Sr<sub>3</sub>Fe<sub>2</sub>O<sub>7-δ</sub>'. Together they form a unique fingerprint.

    Cite this