Synthesis and characterization of CeLaMO2 (M: Sm, Gd, Dy) compounds for solid ceramic electrolytes

Abstract

In this study, pure CeO2 and Ce0.85La0.10M0.05O2 (M: Sm3+, Gd3+, Dy3+) solid electrolytes were synthesized using the sol-gel method and sintered at 1350?C for 12 h. X-ray diffraction (XRD) was used for crystal structure characterization of the ceramic solid electrolytes. After sintering, all prepared solid electrolytes were indexed to be cubic crystal lattices. The thermal properties of the prepared samples were investigated by thermogravimetric (TG) and differential thermal analysis (DTA) methods. The surface properties of the grain structure of the ceramic solid electrolytes were evaluated by scanning electron microscopy (FE-SEM) confirming the average grain size of about 1 ?m. The electrochemical impedance spectroscopy technique was used to investigate AC electrical properties of prepared solid electrolytes. The conductivity values at 750?C of the Ce0.85La0.10Sm0.05O2, Ce0.85La0.10Gd0.05O2 and Ce0.85La0.10Dy0.05O2 and pure CeO2 were found to be 1.10 ? 10?3 S/cm, 3.05 ? 10?4 S/cm, 8.85 ? 10?4 S/cm and 8.44 ? 10?10 S/cm, respectively. The characterization results showed that the La-Sm co-doped CeO2 sample can be used as a ceramic electrolyte in intermediate temperature solid oxide fuel cells (IT-SOFC).

Development of a new system of solid ionic conductors based on multi-doped ceria for application in IT-SOFCs

“…With the further comparison of the values for conductivity obtained for similar materials based on oxygen ion conductors (multi-doped ceria materials) investigated in previous literature reports [12,19,20,24,25,[30][31][32][33][34]37], it may be observed that present results for the SPRT samples are in the similar range while for the MGNP samples are noticeably higher. What is more, referring to some existing studies [32,38], the present results are higher for a whole order of magnitude even for the SPRT samples.…”

Advances and challenges in symmetrical solid oxide electrolysis cells: materials development and resource utilization

“…108 To improve its performance, Sm 3+ , Gd 3+ , and Dy 3+ are doped. 109 Sm 3+ and Gd 3+ doped CeO 2 electrolyte (SDC, GDC) show significantly improved conductivity. GDC and SDC are often combined with YSZ to make use of their advantages.…”