Thermodynamic study on the Y-Ba-Cu-O system by the EMF method

A solid state concentration cell consisting of a test electrode in which member oxides in the Y-Ba-Cu-O system are contained with a NiO-Ni reference electrode, was constructed and the EMF was measured. From the EMF the free energy change of the reaction generating EMF and the enthalpy and entropy changes were calculated. The standard enthalpies of formation and standard entropies of the member oxides were also calculated and the standard enthalpies of formation were compared with those determined by calorimetry. Good agreement was found. (orig.)