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

International audienceMisfit 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