Effect of fuel choice on conductivity and morphological properties of samarium doped ceria electrolytes for IT-SOFC

Authors: BURCU AYGÜN, VEDAT SARIBOĞA, MEHMET ALİ FARUK ÖKSÜZÖMER

Abstract: The present investigation is emphasized on the effect of various combustion agents on the crystal properties, surface microstructure, and oxygen ion conductivity of 20% mole-Sm doped ceria (Ce_0.80Sm_0.20O_1.90/SDC₂₀) ceramics as solid electrolyte for ITSOFCs. The most widely used combustion agents for engineering ceramic production as ethylene glycol, diethylene glycol, triethylene glycol, L-alanine, L-valine, glycine, citric acid monohydrate, urea, and EDTA-citric acid were compared in terms of SDC₂₀ properties. X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and electrochemical impedance spectroscopy (EIS) were used to determine the microstructure properties, crystal structure and ionic conductivity of SDC₂₀ powder. XRD pattern of the ceramics revealed the formation of single-phase fluorite structure. According to the results of electrochemical analysis, the maximum total ionic conductivity was observed in SDC20 electrolyte synthesized using triethylene glycol as the fuel among all the synthesized electrolytes (5.72 x 10^-2 S.cm^-1).

Keywords: Ionic conductivity, Sol-gel processes, Samaria-doped-CeO₂

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