Akademik Veri Yönetim Sistemi
3. BİLSEL INTERNATIONAL TRUVA SCIENTIFIC RESEARCHES and INNOVATION CONGRESS 25-26 MAY, 2024, ÇANAKKALE/TÜRKİYE, Çanakkale, Türkiye, 25 - 26 Mayıs 2024, cilt.1213, ss.1213
In this paper, Er2O3 and Ho2O3 co-doped Bi2O3 compositions were synthesized by the solid-state reaction
method under air conditions, and then each of the fabricated compositions was heat treated at different
temperatures to see the impact of the annealing process on phase formation and conductivity. The XRD profiles
at room temperature confirmed that all compositions were stabilized with cubic δ-phase due to the single-phase
peaks appearing on the patterns. It was observed that the average crystal size increased with increasing
annealing temperatures, indicating low crystallinity. The predicted lattice constants for the stabilized phase were
smaller than those of the pure phase (5.65Å), indicating lattice shrinkage. The temperature-dependent DTA
curves did not contain endothermic or exothermic peaks indicating any phase transition, but thermal peaks
indicating order-disorder transition (ODT), which were related to the anion sublattice of the lattice matrix, were
quite evident on the curves at approximately 600 °C. Temperature-dependent Arrhenius plots also clearly
revealed the ODT effect, with a sudden increase in conductivity around 600 °C. The highest conductivity was
reached in the composition (Bi2O3)0.88(Er2O3)0.04(Ho2O3)0.08 synthesized by heat treatment at 800 °C, with 0.47
S/cm. The FE-SEM images clearly showed the effect of an increase in annealing temperature on grain
distribution and size. The EDAX pattern of composition (Bi2O3)0.88(Er2O3)0.08(Ho2O3)0.04 showed that all
elements were included in the mixture without impurity atoms.