Temperature investigation of the electrical properties of the 0.9SnO2 + 0.1 CuO two-phase composite by impedance spectroscopy

The electrical properties of 0.9SnO^sub 2^ + 0.1CuO two-phase polycrystalline composite films are investigated by impedance spectroscopy in the temperature range 293-393 K. The main results are presented in the form of frequency dependences of the real part Z' and the imaginary part Z'' of the total impedance Z for the samples under investigation at different temperatures. The results obtained are used to construct the loci of the impedance Z in the Z' and Z'' coordinates. The loci can be represented by two weakly overlapping semicircles characterized by two parallel equivalent circuits R ^sub 1^ C ^sub 1^ and R ^sub 2^ C ^sub 2^ connected in series. The activation energies of individual components contributing to the electrical conductivity of the sample are evaluated from the temperature dependences of the electrical properties determined by impedance spectroscopy for the 0.9SnO^sub 2^ + 0.1CuO two-phase composite. An equivalent electrical circuit corresponding to the total electrical response of all individual components is proposed for the composite studied.[PUBLICATION ABSTRACT]