Samarium doped ceria (SDC) synthesized by a metal triethanolamine complex decomposition method: Characterization and an ionic conductivity study

Samarium doped ceria (SDC) powders as solid electrolyte ceramics were successfully prepared via thermal decomposition of metal organic complexes containing triethanolamine (TEA) as a ligand. The SDC powders synthesized using various samarium doping contents were characterized by X-ray diffractometry, scanning electron microscopy, X-ray absorption spectroscopy, energy dispersive X-ray spectroscopy and Brunauer-Emmett-Teller (BET) analysis. The influences of samarium doping and the calcination temperature on the characteristics of the SDC materials were thoroughly investigated. An appropriate temperature for SDC powder calcination was identified by thermogravimetric analysis to be 600 °C. After sintering the calcined SDC powders at 1500 °C to obtain highly dense ceramic pellets, the electrical conductivity of the materials was examined by impedance spectroscopy. The influence of percentage of Sm3+ dopants in SDC materials on the observed conductivity were explained by correlating with the detailed analysis of the local structure and environment of Sm3+ within the SDC materials by using X-ray absorption spectroscopy. The conductivities of the SDC products reported in this work indicate that they are promising candidates for solid electrolytes in solid oxide fuel cell applications.