Multidoped CeO2 single-phase as electrolyte for IT-SOFC

Abstract

This paper explores the application of nanosized, sintered, non-stoichiometric CeO2 with six dopants Ce0.8Nd0.0025Sm0.0025Gd0.005Dy0.095Y0.095O2-δ (CNSGDY), synthesized via modified glycine-nitrate procedure (MGNP) and room temperature self-propagating reaction (SPRT) for fuel cells. The composition, microstructure, and morphology of CNSGDY samples were analyzed using XRD, Raman spectroscopy, SEM, and EDS. The concentration of O2− vacancies, enabling the improvement of ionic conduction, was measured by the deconvolution procedure of additional Raman modes (250 cm−1 (2TA), 560 cm−1 (2LA) and 610 cm−1 (2TO)) and total values for MGNP and SPRT CNSGDY were 15.89% and 16.06%, respectively. Electrochemical performance assessed through EIS ((Electrochemical Impedance Spectroscopy) in the 550–700 °C range revealed a maximum power density of 55 mWcm−2 at 700 °C with SPRT electrolyte. Additionally, the ionic conductivity of the samples was calculated, with the SPRT sample showing superior performance due to higher ionic conductivity values. Differences in power densities between Pt/SPRT/Pt and Pt/MGNP/Pt cells suggest electrode-electrolyte interface and film thickness impacts, guiding future research.