Abstract. Temperature programmed 02 desorption (hereafter denoted reduction, TPR) in a high vacuum system equipped with a mass spectrometer was used to investigate the oxygen loss as a function of temperature in perovskites materials of the type Lno.65Sr~3Mn0.sCoo.203 (Ln = Im--Gd), which are important as potential electrode materials for solid oxide fuel cells (SOFC). The materials were prepared either by spray drying as described in [l] or via the Pechini method [2] for the perovskites with Ln = Nd-Gd.The TPR experiments were carried out at temperatures 300-1000 K with various heating rates 13 in order to determine the onset of reduction and the activation energy of reduction for each perovskite. The experiments were carried out in an ultra high vacuum chamber (base pressure 10 t~ mbar after baking) equipped with a quadrupole mass spectrometer [3,4]. Additional oxygen adsorption was attempted at several adsorption temperatures but no discrete oxygen desorption peaks were observed before the onset of reduction. Pro.6sSr0.3Mno.~Coo.203 was tound to have the lowest reduction activation energy (149+19 kJ/mol) and the lowest temperature, TR, for onset of reduction (750 K). On the other hand Gdo.65Sro.3Mno.sCoo.203 was found to have the highest reduction activation energy (232+38 kJ/mol) while the TR was about 850 K. The reduction activation energies follow the sequence Pr
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.