Scalable and facile fabrication of tri-layer electrolytes by reactive sputtering for efficient and durable solid oxide fuel cells

Scalable and facile fabrication of large-area electrolytes by physical vapor deposition (PVD) for efficient and durable solid oxide fuel cells (SOFCs) is a promising way to tackle the issues such as elemental diffusion and warpage of cells resulted from high-temperature sintering in conventional wet ceramic methods. Herein, highperformance industrial size, 12 x 12 cm(2), electrolytes are successfully fabricated by reactive sputtering on commercially obtained nickel oxide-yttria-stabilized zirconia (NiO-YSZ) anode without any pretreatment. Electrolytes of 6-mu m-thick with gadolinium-doped ceria (GDC)|YSZ|GDC tri-layer configuration are fabricated with less than 2.5-h sputtering and followed by annealing at 1000 C-degrees, much lower than that adopted in traditional wet process. In combination with traditional La0.6Sr0.4Co0.2Fe0.8O3-delta (LSCF) cathodes, SOFCs with sputtered electrolytes show open circuit voltages close to the theoretical values, excellent electrochemical performances and long-term stability. The initial peak power densities of such cells reach 1.80, 1.24, 0.75 and 0.42 W cm(-2) at 800, 750, 700 and 650 C-degrees, respectively. The performance increases slightly in the initial stage and then stabilizes without degradation during the 300-h stability test under a constant voltage of 0.8 V at 650 C-degrees. The scaled-up deposition area and the high deposition rate (-2.5 mu m h(-1)) show promising opportunities in the mass production of SOFCs using reactive sputtering.