Compositional Engineering of a La1-xBaxCoO3-δ-(1- a) BaZr0.9Y0.1O2.95 (a = 0.6, 0.7, 0.8 and x = 0.5, 0.6, 0.7) Nanocomposite Cathodes for Protonic Ceramic Fuel Cells

Laura Rioja-Monllor; Carlos Bernuy-Lopez; Marie-Laure Fontaine; Tor Grande; Mari-Ann Einarsrud

doi:10.3390/ma12203441

Compositional Engineering of a La_1-xBa_xCoO_3-δ-(1- a) BaZr_0.9Y_0.1O_2.95 (a = 0.6, 0.7, 0.8 and x = 0.5, 0.6, 0.7) Nanocomposite Cathodes for Protonic Ceramic Fuel Cells

Materials (Basel). 2019 Oct 21;12(20):3441. doi: 10.3390/ma12203441.

Authors

Laura Rioja-Monllor¹, Carlos Bernuy-Lopez², Marie-Laure Fontaine³, Tor Grande⁴, Mari-Ann Einarsrud⁵

Affiliations

¹ Department of Materials Science and Engineering, NTNU Norwegian University of Science and Technology, 7491 Trondheim, Norway. laura.rioja-monllor@sandvik.com.
² Department of Materials Science and Engineering, NTNU Norwegian University of Science and Technology, 7491 Trondheim, Norway. carlos.bernuy-lopez@sandvik.com.
³ SINTEF Industry, 0314 Oslo, Norway. Marie-Laure.fontaine@sintef.no.
⁴ Department of Materials Science and Engineering, NTNU Norwegian University of Science and Technology, 7491 Trondheim, Norway. tor.grande@ntnu.no.
⁵ Department of Materials Science and Engineering, NTNU Norwegian University of Science and Technology, 7491 Trondheim, Norway. mari-ann.einarsrud@ntnu.no.

Abstract

Compositionally engineered a La_1-xBa_xCoO_3-δ-(1-a) BaZr_0.9Y_0.1O_2.95 (a = 0.6, 0.7, 0.8 and x = 0.5, 0.6, 0.7) (LBZ) nanocomposite cathodes were prepared by oxidation driven in situ exsolution of a single-phase material deposited on a BaZr_0.9Y_0.1O_2.95 electrolyte. The processing procedure of the cathode was optimized by reducing the number of thermal treatments as the single-phase precursor was deposited directly on the electrolyte. The exsolution and firing of the cathodes occurred in one step. The electrochemical performance of symmetrical cells with the compositionally engineered cathodes was investigated by impedance spectroscopy in controlled atmospheres. The optimized materials processing gave web-like nanostructured cathodes with superior electrochemical performance for all compositions. The area specific resistances obtained were all below 12 Ω·cm² at 400 °C and below 0.59 Ω·cm² at 600 °C in 3% moist synthetic air. The resistances of the nominal 0.6 La_0.5Ba_0.5CoO_3-δ-0.4 BaZr_0.9Y_0.1O_2.95 and 0.8 La_0.5Ba_0.5CoO_3-δ-0.2 BaZr_0.9Y_0.1O_2.95 composite cathodes were among the lowest reported for protonic ceramic fuel cells cathodes in symmetrical cell configuration with ASR equal to 4.04 and 4.84 Ω·cm² at 400 °C, and 0.21 and 0.27 Ω·cm² at 600 °C, respectively.

Keywords: cathode; exsolution; proton ceramic fuel cells (PCFC).

Abstract

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