Specific features in the synthesis, crystal structure and electrical conductivity of BICUTIVOX

The formation of solid solutions Bi4V2 − xCux/2Tix/2O11 − x (0.025 ≤ x ≤ 0.5) known as BICUTIVOX, synthesized by three different methods (a conventional solid-state synthesis, solid-state synthesis enhanced by mechanical activation, and through liquid precursors), has been studied. Based on crystal structure investigations carried out at different temperatures, ranges of stability and temperatures of phase transitions for different polymorphous modifications have been defined. The morphology and the local chemical composition of the ceramic samples obtained have been studied. Thermal expansion coefficients have been measured. The electrical conductivity of ceramic samples has been investigated in a wide range of temperatures and partial oxygen pressures.

► We studied solid solutions Bi4V2 − xCux/2Tix/2O11 − δ synthesized using tree methods. ► High electrical conductivity (10 − 2 Sm − 1cm − 1 at 750 °C) is characteristic of BITICUVOX. ► Non-controlled micro-impurities appear during the synthesis. ► Crystal structure does not remain stable during long term annealing.