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arXiv · 1910.01715

Temperature-programmed reduction and dispersive X-ray absorption spectroscopy studies of CeO2-based nanopowders for intermediate-temperature Solid-Oxide Fuel Cell anodes

Marina S. Bellora·Joaquín Sacanell·Cristián Huck-Iriart·Analía L. Soldati·Susana A. Larrondo·Diego G. Lamas
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Abstract

In this work, we study the influence of the average crystallite size and dopant oxide on the reducibility of CeO2-based nanomaterials. Samples were prepared from commercial Gd2O3-, Sm2O3- and Y2O3-doped CeO2 powders by calcination at different temperatures ranging between 400 and 900C and characterized by X-ray powder diffraction, transmission electron microscopy and BET specific surface area. The reducibility of the samples was analyzed by temperature-programmed reduction and in situ dispersive X-ray absorption spectroscopy techniques. Our results clearly demonstrate that samples treated at lower temperatures, of smallest average crystallite size and highest specific surface areas, exhibit the best performance, while Gd2O3-doped ceria materials display higher reducibility than Sm2O3- and Y2O3-doped CeO2.

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Marina S. Bellora, Joaquín Sacanell, Cristián Huck-Iriart, Analía L. Soldati, Susana A. Larrondo, Diego G. Lamas. 2019-10-03. Temperature-programmed reduction and dispersive X-ray absorption spectroscopy studies of CeO2-based nanopowders for intermediate-temperature Solid-Oxide Fuel Cell anodes. https://doi.org/10.4236/msa.2019.1010045

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