YSZ layers by pulsed-MOCVD on solid oxide fuel cell electrodes

An experimental pulsed-MOCVD system was used to produce solid zirconia, and yttria-stabilized-zirconia (YSZ) films on porous nickel-cermet samples. A total of six candidate metal–organic precursors for zirconia and three for yttria were investigated. Three precursor solutions for YSZ were identified as desirable for pulsed-MOCVD processing. Under optimal deposition conditions, precursor conversion efficiency of 90% was achieved at film growth rates of 6–7.5 μm h−1 at deposition temperature of 525 °C. Film growth rates were determined from in situ color shift method, and by scanning electron microscope examination of the deposited layer. Powder X-ray diffraction of the film surface identified the layer as YSZ. Layers deposited on Ni-cermet samples remained intact on cooling. Results for thicker (10 μm or greater) YSZ layers indicate the process could be developed for low-cost solid oxide fuel cell electrodes, but co-development of electrode processing and YSZ electrolyte deposition will be crucial.