Fabrication and Characterization of Ni-GDC/GDC Half-Cell Manufactured By Tape Casting and Reactive Magnetron Sputtering Processes As Half-Cell for SOFC

Abstract

In this work, anode-supported solid oxide fuel cells (SOFCs) has been manufactured by tape casting and co-sintering technique. NiO and GDC (10% Gd), used for the anode-supported (as) and the anode functional layer (afl) powders, with an initial size of -40 mesh and -100 mesh particle size respectively, were milled by using zirconia balls in a Turbula-(System Schatz from WAB) times up to 24 to 48 hours. Half-cell, 28 mm of diameter, Ni-GDC10 composite anodes have been elaborated by slurry based tape casting method for anode supported solid oxide fuel cell. The chosen ceramic powders in suspension were prepared with the mass ratio of 65:35 for NiO to GDC10. The microstructural morphological /porosity/surface features of the half-cell were analyzed by Scanning Electron Microscopy (SEM), XRD and 3D profilometry before and after different annealing treatment. Pycnometry and porosimetry techniques were primarily used to determine pore size and pore volume by equation Washburn and Ideal gas law-method. Depending on the results, work on the support anode (AS) Ni-GDC will continue in particular to avoid the presence of the residual phase of carbon resulting from the use of an agent poro formers with graphite. The obtained cell after sintering was seen without any deformation or crack. One of the ways followed to remove the residual graphite is increase of the temperature and / or sintering time.The pre-sintered anode green tape was coated with a GDC electrolyte film by reactive magnetron sputtering using PEM techniques. An Alcatel SCM650 sputtering chamber was used for synthesizing the dense GDC layers. A Ce-Gd metallic target (90-10% at) was powered by a pinnacle + pulsed current generator from Advanced Energy. The structural, microstructural and morphological features of the half-cells were determined by XRD, SEM and 3D profilometry as deposited and after different annealing treatments. Finally, the EIS measurements were performed on Ni-GDC/GDC half-cells under 60 sccm nitrogen by the means of a Solartron SI 1260 impedance / gain analyzer from 20 MHz to 0.1 Hz with 11 points per decade.