Scalable fabrication process of thin-film solid oxide fuel cells with an anode functional layer design and a sputtered electrolyte

The fabrication process for anode-supported thin-film solid oxide fuel cells (SOFCs) was investigated by using scalable and cost-effective methods. The anode functional layer (AFL) was introduced on the surface of the substrate to stably deposit the thin-film electrolyte. In previous studies, the AFL has been generally designed to increase the catalytic activity; however, in this study, additional design parameters including the roughness and density were controlled to achieve a pinhole-free thin-film electrolyte and structural stability. Through the developed process, button and large-sized cells were fabricated, and the electrochemical performance evaluation showed potential power density and impedance values at relatively low operating temperature. Microstructural analyses showed that each layer of the AFL, electrolyte, and cathode was uniformly coated on the substrate. The thin-film electrolyte was densely deposited without cracks or pinholes. The electrochemical performance and microstructure confirmed that the developed thin-film SOFCs are reliable and reproducible without costly processes or materials.