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BIMEVOX solid electrolytes are produced by partly substitution of
vanadium of bismuth vanadium, Bi4 V2O1), by different metals (ME: Cu, Ni, Ti, Zr ,. . .), and have tetragonal crystal structure at room temperature with the highest ionic conductivity at moderate temperature. BICUVOX.I in which 10 atomic percent of vanadium of Bi4V2O11 has been substituted by Cu is the most famous member of the mentioned oxide ion conductors and at 400 DC its ionic conductivity (0.02 S/cm) is more than 50 to 100 times of stabilized zirconia (the most famous solid electrolyte) at the same temperature. In the present work, BICUVOX.I compound has been synthesized by solid-state method and its crystal structure and probable phase transformations at different temperatures were determined by X-ray diffraction and thermal analysis (DTA/TG) methods. Ionic
conductivity of the BICUVOX.I dense samples was determined in the range of
] 00- 750 DC using impedance spectroscopy method. The results showed that BICUVOX.I synthesized at 650 DC with tetragonal crystal structure is stable up to the melting point and just
ordering/disordering transformation of
oxygen vacancies occurs at around 400¬500 "C. Ionic conductivities at moderate temperatures (300-500 ) were obtained more better than stabilized zirconia, with lower activation energies (0.4 eV versus
1.1 eV).