Electrical properties of Nb2(1–y)Ta2yO5-based ceramics

Resumo

We have studied the electrical properties of ceramic Nb_2(1–y)Ta_2yO₅ samples, examined the dispersion of the real part of their dielectric permittivity ε′ at room temperature, and assessed their lattice dielectric permittivity ε′_∞ The temperature dependences ε′(T) have been obtained at different frequencies, and the dielectric loss tan δ has been evaluated as a function of measuring electric field frequency and temperature. The direct-current conductivity (σ_dc) of the solid solutions has been determined at room temperature. Using impedance spectroscopy data, we have obtained temperature dependences of σ_dc for the Nb_2(1–y)Ta_2yO₅ ceramics and evaluated the activation enthalpy for charge transport in these materials in different temperature ranges.