Preparation and characterization of Ce_(1-x)Sm_xO_(2-δ) (x = 0.1-0.3) as electrolyte material for intermediate temperature SOFC

摘要

The effect of Sm doping on CeO_2 for its use as a solid electrolyte material for intermediate temperature solid oxide fuel cells (IT-SOFCs) has been explored here. Ce_(1-x)Sm_xO_(2-δ) (x = 0.1-0.3) samples are successfully synthesized by carbonate co-precipitation method. TG-DTA, XRD, Raman, UV-Vis, FT-IR, SEM and ac-impedance are used for structural and electrical characterization. From the XRD patterns, well-crystalline cubic fluorite structured solid solution is confirmed. Lattice parameters increased with increase in Sm~(3+) while the crystallite size decreased, the optical absorption spectra exhibits a red shift for Sm~(3+) doped CeC>2. Raman spectra show an intense peak at 463 cm~(-1), a characteristic peak for doped ceria. SEM shows cluster like particles. Based on ac-impedance data, the total oxygen ionic conductivity is highest for Ce_(0.8)Sm_(0.2)O_(2-δ) in the temperature range of 473-623 K.