Deposition and Characterizations of Pt/YSZ Nanocomposite Thin Films for Micro-SOFCs

Microfabricated solid oxide fuel cells (micro-SOFCs) have gained much attention as a promising technology to portable power applications. Pt and perovskite materials, the two common cathodes used in micro-SOFCs, have significant technical challenges due to their microstructural instability and low bulk conductivity, respectively. Pt/YSZ nanocomposites which combine the high electronic conductivity and catalytic activity of Pt and high ionic conductivity of YSZ, is a promising electrode candidate to improve the performances of micro-SOFCs. In this approach, Pt/YSZ nanocomposite thin films are deposited via RF co-sputtering. The structural, morphological, and electrical properties of the nanocomposite thin films were systematically studied. The thin films have been verified through SEM to be dense, crack-free, and homogeneous in thickness. The film crystallinity increases with Pt content and the thermal treatment. Upon increasing Pt content, the nanocomposite thin films gradually transform from dominant ionic-conducting to mixed ionic/electronic and eventually metallic characteristic behavior.