Progress in Metal-Supported Axial-Injection Plasma Sprayed Solid Oxide Fuel Cells Using Nanostructured NiO-Y_(0.15)Zr_(0.85)O_(1.925) Dry Powder Anode Feedstock

摘要

A composite NiO-Y_(0.15)Zr_(0.85)O_(1.925) (YSZ) agglomerated feedstock having nanoscale NiO and YSZ primary particles was used to fabricate anodes having sub-micrometer structure. These anodes were incorporated into two different metal-supported SOFC architectures, which differ in the order of electrode deposition. The composition of the composite Ni-YSZ anodes is controllable by selection of the agglomerate size fraction and standoff distance, while the porosity is controllable by selection of agglomerate size fraction and addition of a sacrificial pore-forming material. A bi-layer anode was fabricated having a total porosity of 33% for the diffusion layer and 23% porosity for the functional layer. A power density of 630 mW/cm~2 was obtained at 750℃ in humidified H_2 with cells having the bi-layer anode deposited on the metal support. Cells having the cathode deposited on the metal support showed poor performance due to a significant number of vertical cracks through the electrolyte, allowing excessive gas cross-over between the anode and the cathode compartments.