Akademik Veri Yönetim Sistemi
Ceramics International, cilt.50, sa.17, ss.29358-29367, 2024 (SCI-Expanded)
In the study, we synthesized the (BiO1.5)0.88(ErO1.5)0.08(HoO1.5)0.04 and (BiO1.5)0.88(ErO1.5)0.04(HoO1.5)0.08 ternary compositions using the solid–state reactions in an atmosphere of air. All compositions were then heated to 650, 700, 750, and 800 °C to observe how the calcination temperature impacts phase stability and conductivity. All XRD patterns suggested that the cubic δ–phase, a high–ion conductor, became stable at room temperature. Depending on the temperature, the DTA curves revealed that some compositions had an endothermic peak at around 600 °C, indicating an order–disorder transition wholly related to anion sublattice arrangement without a phase transition. At 700 °C, the highest conductivity was found to be 0.482 S/cm for the (BiO1.5)0.88(ErO1.5)0.04(HoO1.5)0.08 composition calcined at 800 °C, and this conductivity is greater than that of a single–doped (BiO1.5)0.80(ErO1.5)0.20 system. The FE–SEM images indicated that calcination at 650 °C and 700 °C, which are below the phase transition temperature (729 °C) from α–phase to cubic δ–phase, results in atom aggregation and porosity on the surface. Besides, the calcination temperature was shown to significantly impact grain sizes, with compositions produced with a calcination at 800 °C exhibiting bigger grains than lower ones.