Mixed Proton Electron Conductivity of Calcium Chromate(V) Apatite

摘要

This is the first report to investigate on the electrical conductivity of unusual high valence state pentavalent chromium oxides in terms of defect thermodynamics. Calcium chromium(V) apatite was prepared as a single phase, and the electrical conductivity was examined as a function of oxygen partial pressure pO_2. The conductivity was increased at higher pO_2 in wet atmosphere but it was not dependent on pO_2 in dry atmosphere. The water concentration cell gives stable electromotive force. The features disclosed that the chromium(V) apatite reveals proton electron mixed conductivity under wet oxidative condition.