Effect of MoO(3) concentration on sintering and electrical properties of SiO(2)-containing neodymium-doped ceria electrolytes

The effects of MoO(3) concentration on the sintering and electrical properties of Ce(0.8)Nd(0.2)O(1.9) + 500 ppm SiO(2) (NDCSi) and (Ce(0.8)Nd(0.2)O(1.9))(1 -) (x)(MoO(3))(x) + 500 ppm SiO(2) (x = 0.01, 0.02, 0.03, 0.04, 0.05, NDCSi + 1MoO(3), NDCSi + 2MoO(3), NDCSi + 3MoO(3), NDCSi + 4MoO(3), NDCSi + 5MoO(3)) prepared through a modified sol-gel method were systematically investigated. The structures and ionic conductivities were characterized by XRD. FE-SEM and EIS. The results indicated a sharp increase in densification and conductivity for the system of NDCSi containing small amount of MoO(3). It shows that NDCSi + 3MoO(3) exhibited much higher relative density (RD = 96%), higher conductivity (sigma(t) = 1.25 x 10(-2) S cm(-1) at 600 degrees C) and lower activation energy (E(a) = 0.81 eV) compared with NDCSi and the other MoO(3) doped-NDCSi samples. Furthermore, MoO(3) could be used as an effective sintering aid and a grain boundary scavenger for NDCSi system. And we obtained the optimal amount of the MoO(3) is 3 mol%. Crown Copyright (C) 2011 Published by Elsevier Masson SAS. All rights reserved