The preparation and properties of copper beta alumina

Abstract

The preparation of copper beta alumina from sodium beta alumina is described. The lattice parameters, phase contents, densities and expansion coefficients were determined. The electrolytic substitution of Cu + in the beta-alumina structure was not complete as a small proportion of Na + remained within the material. The thermal stability of copper beta alumina was investigated. The ionic conductivity of copper beta alumina was measured using both solid copper and molten salt electrodes and an ac bridge. It was found that only at high temperatures was there agreement between the different techniques due to polarization effects using solid electrodes. The electronic conductivity was measured using the Wagner asymmetric polarization method and was found to be negligible.