The partial molar enthalpy of incorporation of oxygen (Aox/f) and enthalpy of formation (Af/f) have been measured via high-temperature reaction calorimetry for YBa2Cu3-xMxOy (where M = Ni, Zn) in the composition range 0.0 < x lt; 0.18. Aox/f and Af /f values were nearly independent of dopant for both Ni and Zn, with enthalpies of oxidation in the range - 86 to -110 kJ/(mol 1/2O2) and enthalpies of formation in the range -110 to -118 kJ/mol. The independence of thermodynamic behavior from superconducting properties is consistent with an electronic mechanism for Tc suppression in Zn-doped YBCO superconductors. Oxygen contents, lattice parameters, and Tc measurements are also reported.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Energy Engineering and Power Technology
- Electrical and Electronic Engineering