AC conduction mechanism of the zinc potassium diphosphate

Zinc potassium pyrophosphate K2ZnP2O7 was synthesized using the conventional solid-state reaction. X-ray powder diffraction analysis proves the formation of a pure phase which crystallizes in the tetragonal system. The electrical conductivity and modulus characteristics of the system have been investigated in the temperature and the frequency range 614-718 K and 200 Hz-1 MHz, respectively, by means of impedance spectroscopy. The alternating current (AC) conductivity for grain contribution follows the universal Jonscher's power law. The frequency exponent s is temperature independent and equal to 0.8. The QMT model was proposed to be the most suitable model to characterize the electrical conduction mechanism in the titled sample. Dielectric data were analyzed using complex electrical modulus M* at various temperatures. The bulk relaxation time was found from the peaks position of the above spectra and the thermodynamic parameters were also found using the Eyring theory.