Coral Microstructure of Graded CGO/LSCF Oxygen Electrode by Electrostatic Spray Deposition for Energy (IT-SOFC, SOEC)

The goal of this work was to fabricate a composite based on Ce0.9Gd0.1O1.95 (CGO) and La0.6Sr0.4Co0.2Fe0.8O3- (LSCF) as a porous and thin oxygen electrode film adherent to (ZrO2)0.92(Y2O3)0.08 (YSZ) substrate by electrostatic spray deposition in order to improve durability in solid oxide fuel cells operating at intermediate temperature (IT-SOFC) and solid oxide electrolyzer cells. A simultaneous gradient in composition and in porosity of CGO/LSCF coatings has been successfully obtained by choosing proper deposition parameters and physicochemical properties of the precursor solution. Detailed microstructural characterization was made by SEM and completed with 3D focused ion beam-scanning electron microscope (FIB-SEM) tomography. The graded composition rich in CGO close to YSZ and rich in LSCF at the electrode surface has been investigated by energy dispersive X-ray spectroscopy through line profile of coral microstructure. Only cubic CGO and cubic LSCF perovskite were detected by XRD in deposited coatings after heat treatment at 900 degrees C for 2h.