Misfit Ca-cobaltite from a mixture of mollusk shells and cobalt oxide as potential SOFC cathode material

Erik B. G. A. Fulgencio (1) , Klivia P. V. Melo (1) , Rinaldo M. Silva (1) , Joao P. F. Grilo (2) , Vincent Caignaert (3) , Moises R. Cesario (3) , Liszandra F. A. Campos (1) , Daniel A. Macedo (1)

1 UFPB - Universidade Federal da Paraiba / Federal University of Paraiba
2 Universidade de Aveiro
3 CRISMAT - Laboratoire de cristallographie et sciences des matériaux

Misfit Ca-cobaltites of nominal composition Ca3Co4O9-delta (C349) have attracted great attention as Solid Oxide Fuel Cell (SOFC) cathode material. The present work reports, for the first time, the solid-state synthesis of C349 powders from a mixture of cobalt oxide and mollusk shells, a natural source of calcium carbonate. The synthesized material was studied by X-ray diffraction, with Rietveld refinement of the XRD data, and Transmission Electron Microscopy (TEM). Screen-printed C349 porous electrodes were fired on both sides of dense gadolinia-doped ceria ceramics and electrochemically characterized by impedance spectroscopy at 700-800 C in air. The measured area specific resistance (ASR of 1.47 Omega cm(2) at 800 degrees C in air) is in line with literature data for similar cathodes prepared by other synthetic routes.

Mots clés: Powders solid state reaction; X-ray methods; Impedance; Fuel cells; Ca3CO4O9-delta

Domaines: Chimie; Cristallographie; Matériaux; Chimie théorique et/ou physique

Erik B. G. A. Fulgencio, Klivia P. V. Melo, Rinaldo M. Silva, Joao P. F. Grilo, Vincent Caignaert, et al.. Misfit Ca-cobaltite from a mixture of mollusk shells and cobalt oxide as potential SOFC cathode material. Ceramics International, 2017, 43 (12), pp.9564-9567. ⟨10.1016/j.ceramint.2017.04.099⟩. ⟨hal-02175425⟩