Effects of strontium gallate additions on sintering behavior and electrical conductivity of samaria-doped ceria

The densification behavior and electrical conductivity of Ce0.8Sm0.2O1.9 ceramics were investigated with the strontium gallate concentration ranging from 0 to 5 mol%. The sintered density was found to increase rapidly up to 0.5 mol% Sr2Ga2O5, and then to decrease with further additions. Dense Ce0.8Sm0.2O1.9 ceramics with 97% ofthe theoretical density could be obtained for 0.5 mol% Sr2Ga2O5-added specimen sintered at 1250 degrees C for 5 h, whereas pure Ce0.8Sm0.2O1.9 Ceramics needed to be sintered at 1550 degrees C in order to obtain an equivalent theoretical density. Electrical conductivity was measured as a function of dopant content, over the temperature range of 350-550 degrees C in air. Total conductivity of 0.5 mol% Sr2Ga2O5-added specimen showed the maximum conductivity of 1.91 X 10(-2) Omega(-1) cm(-1) at 500 degrees C. The addition of strontium gallate was found to promote the sintering properties and electrical conductivities Of Sm2O3-doped CeO2. (C) 2008 Elsevier B.V. All rights reserved.