Fabrication and Evaluation of Composite Ionic Conductors by the Use of a Temperature and Concentration Gradient

Abstract

AgI–Al2O3 composites were fabricated by precipitating Agl grains within micropores of porous alumina pellets utilizing reaction between AgF and Nal solutions supplied from separately held containers. The effect of temperature of the Nal solution on the texture and morphology of the composites was studied. With respect to all the composites examined in this study, the initially formed part did not show grain orientation, while the subsequently formed part showed significant grain orientation, and the crystallite sizes along [001] and [hh0] at the initially formed part almost agreed with each other. With an increase in distance from the initially formed part, the crystallite size along [001] as well as that along [hh0] changed and the degree of the change depended on the temperature of the solution. A growth mechanism based on the experimental results is proposed.