Synthesis and properties of gadolinium doped ceria electrolyte for IT-SOFCs by EDTA-citrate complexing method

• Published in: Journal of alloys and compounds Vol. 695; pp. 871 - 876
• Main Authors: Anjaneya, K.C., Singh, Mahander Pratap
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 25-02-2017
• Subjects: EDTA-citrate complexing method; Electrochemical impedance spectroscopy; Oxygen ion conductivity; Solid oxide fuel cell; Solid oxide fuel cell; Oxygen ion conductivity; EDTA-citrate complexing method; Electrochemical impedance spectroscopy
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2016.10.175

In the present study, gadolinium doped ceria (Ce0.8Gd0.2O2−δ, GDC) electrolytes at different pH have been successfully prepared by EDTA-citrate complexing method for intermediate temperature solid oxide fuel cells (IT-SOFCs). XRD, Raman, FE-SEM, TEM and electrochemical impedance spectroscopy are used for structural and electrical characterizations. XRD patterns of the GDC powder calcined at 873 K for 5 h exhibits the cubic fluorite structure with space group Fm3m. Raman spectra of sintered GDC powder confirms the formation solid solution in corroboration with XRD data. FE-SEM images of sintered GDC pellets at different pH shows well defined grains separated from grain boundaries with good densification. Highest relative density (99%) is obtained for sintered GDC pellet with pH = 10. Electrical conductivity of GDC depends on pH of the solution and the maximum conductivity is 1.6 × 10−2 S cm−1 at 973 K with pH = 10. These preliminary results indicate the possible application of GDC as a potential electrolyte for IT-SOFCs.
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•Gd3+ doped ceria at different pH were synthesized by EDTA-citrate complexation.•Crystallite sizes of calcined GDC powder decreases with increase of pH.•Raman spectrum of sintered GDC powder confirms the formation of solid solution.•FE-SEM images of GDC shows well defined grains separated from grain boundaries.•GDC at pH = 10 exhibits the highest oxygen ionic conductivity of 1.6 × 10−2 S cm−1.