Structural and Electrical Changes in BIMNVOX Oxide-Ion Conductor
| Periodical | Defect and Diffusion Forum (Volumes 316 - 317) |
|---|---|
| Main Theme | Defects and Diffusion in Ceramics XII |
| Edited by | D.J. Fisher |
| Pages | 7-22 |
| DOI | 10.4028/www.scientific.net/DDF.316-317.7 |
| Citation | Saba Beg et al., 2011, Defect and Diffusion Forum, 316-317, 7 |
| Online since | May, 2011 |
| Authors | Saba Beg, Shehla Hafeez, Niyazi A.S. Al-Areqi |
| Keywords | AC Impedance, BIMEVOX, Ionic Conductivity, Phase Transition |
| Price | US$ 28,- |
Ceramic solid solutions Bi4MnxV2–xO11–(x/2)–δ in the composition range 0.07 ≤ x ≤ 0.30 were obtained by solid state synthesis. Structural investigations were carried out by using a combination of FT-IR and powder X-ray diffraction technique. Polymorphic transitions (β↔γ and γ′↔γ) were detected by DTA and variation in the Arrhenius plots of conductivity. The solid solutions with composition 0.07 ≤ x ≤ 0.17 are isostructural with the orthorhombic β-phase, and those with x ≤ 0.30 represent tetragonal γ-phase. With increasing Mn concentration, the conductivity of solid solutions increases from 3.684×10-6 (x = 0.07) to 2.467×10-5 (x = 0.17). AC impedance plots show that the conductivity is mainly due to the grain contribution which is evident in the enhanced short range diffusion of oxide ion vacancy in the grains with increasing temperature.
