Ionic Conduction of Impurity-Doped β-Alumina Ceramics

Abstract

Beta alumina (Na2O·11 Al2O3) with addition of MgO, NiO, ZnO, CuO and CaO, respectively, together with Na2O are sintered. Ionic conduction of Na+ and X-ray diffraction of these samples are investigated. Additions of above divalent ions, except for Ca2+, increase the amount of Na+ in β-alumina, leading to an increase in the ionic conduction of Na+ in β-alumina. All divalent ions effective to increase the ionic conduction are components of aluminum spinel. The limiting process of the D.C. ionic conduction of these sintered samples may be the grain-boundary conduction.

Advanced materials for sodium-beta alumina batteries: Status, challenges and perspectives

“…The incomplete wetting is likely caused by impurities at the sodium anode/BASE interface. As reported by a number of researchers, the addition of small amounts of calcium in the starting powders led to a significant increase in resistivity of the final product during BASE fabrication [39,60,65]. The mobility of calcium was observed by Demott et al [66] via addition of radioactive Ca-45 into sulfur electrode of Na-S battery.…”

The dependence of structure and conductivity in three-dimensional phosphate ionic conductors on composition

“…The O~so value decreases with decreasing Na concentration, whereas the aN is almost fixed. This result is in a striking contrast with ~-A1203, which shows a remarkable decrease in a on the replacement of a small quantity of Na + by Ca 2+ [16]. The nuclear magnetic resonance spectrum (NMR) for /~-Al203 suggests that the Ca 2+ incorporated in the conduction plane hinders Na § motion [17].…”

Measurement of Electronic Conductivity in Fe‐Doped β‐Alumina

“…Improvement of electrochemical and physical properties with the use of doping has also been reported (1)(2)(3)(4)(5). We have carried out several studies of doped p-alumina and, in particular, have investigated Fe-doped ~-alumina (6).…”