Electrical Properties of Ag-Doped Barium Titanate Ceramics

Abstract

Temperature dependence of electrical conductivity, thermoelectric motive force and Hall effect, electron spin resonance, X-ray analyses, voltage-current characteristics and voltage dependence of capacitance of the Ag-doped BaTiO₃ ceramics were studied. The semiconducting specimens were obtained by firing the ceramic in nitrogen atmosphere. Charge carriers in the specimens are electrons in view of the sign of Hall electric and thermoelectric motive force. The electron spin resonance spectra of oxygen vacancy with electron capture were observed at solid nitrogen temperature. The g-values of the spectra were 1.946±0.001, 1.932±0.0005 and 1.922±0.003. It is suggested that the anomalous temperature dependence of resistivity is due to the decrease of carrier mobility. A tentative model is proposed also for rectification and capacitance action.