Characterization,electrical conduction and stability of Yb-doped barium cerate prepared by sol-gel method

摘要

Ceramics powder of BaCe_(0.95)Yb_(0.05)O_(2.975) was successfully prepared by sol-gel method.Thermogravimet-ric analysis showed that the-decomposition of the dried powder was completed at 1,000°C.Three strongly exothermic peaks observed in differential thermogravimet-ric signal indicated three major stages of weight loss in the sample.The high crystallinity of sample with orthorhombic structure was confirmed by X-ray diffraction.The loose particles size obtained from scanning electron microscope was in the range of 65-100 run,which is almost in the same range as that observed in particle size distribution.The sample showed a dc conductivity of ~1.3X10~(-4)S cm~(-1)at 650°C and the activation energy,E_a,was found to be 1.4 eV.Result of chemical stability test showed that the compound was unstable in atmosphere containing pure carbon dioxide.