Effect of Temperature and Dwell Time on Phase Formation and Microstructure of β"-Alumina Solid Electrolyte

Powder of β-alumina solid electrolyte with general formula Na0.80Li0.20Al5O8 was prepared by solid state reaction according to the ternary systems Li2O-Na2O-Al2O3. All the calcined powders were heated at different temperatures for 1 h. The XRD results indicate that the β-alumina phase started to form at 1100 C and these consistent with TG/DTA measurements. At constant calcined temperature of 1100 C, When the dwell times was varied in range 5 h to 15 h, it was found that powder consists of β-alumina as a majority phase with a tiny amount of β-alumina and the β-alumina phase purity is about 82 wt% for dwell time of 10 h. The microstructures of β-alumina particles were seen as a layered structural arrangement with hexagonal shape and strong agglomeration between these particles are clearly seen.