Interest in the use of thin film of Ruthenium-Samaria doped ceria cermet (Ru-SDC) as anode in solid oxide fuel cells is increasing due to its high oxygen storage capacity and high chemical and thermal stability. To have enough structural integrity between sputtered Ru-SDC films and underlying substrates, good adhesion property is required. In this work, scratch resistance and failure mode for Ru-SDC films with various SDC composition were investigated using a scratch test method employing linearly increasing load from 1 to 50 N using a 200 μm radius Rockwell C indenter. Scratched surfaces were examined with a field emission scanning electron microscope. Chemical compositions in scratch tracks were analyzed by energy dispersive X-Ray spectroscopy. Critical loads for films with different SDC ratios were assessed and associated failure modes were identified. The highest scratch resistance among tested film compositions was the one that contained 50% of SDC. Failure modes of tested films regardless of the ratio of SDC were identified to be the initiation of tensile cracks with rapid increase of friction coefficient followed by chipping, and eventually the generation of a severe crack network.

Solid oxide fuel cell is a next generation energy conversion device that can efficiently convert the chemical energy of fuel into electrical energy. Fuel flexibility is one of the advantages of SOFCs over other types of fuel cells. SOFCs can operate with hydrocarbon type fuel. While nickel based composite is commonly used in direct methane fueled SOFC anode because of its great catalytic activity for methane reforming, the direct use of hydrocarbon fuels with pure Ni anode is usually insufficient for facile anode kinetics, and also deactivates the anode activity because of carbon deposition upon prolonged operation. In this report, the Ni based anodes with 20 nm thick catalytic functional layers, i.e., Pt, Ru, and Pt-Ru alloy, are fabricated by using the co-sputtering method to enhance the anode activity and power density of direct-methane SOFC operating at 500℃.

The necessity of converting toxic gas has arisen from the usage of perfluorinated compounds (PFCs), volatile organic compounds (VOCs), and hydrocarbon gases in the semiconductor process and laboratories. Also, recent strong regulations on the emission gas from vehicles also present the need for the highly efficient chemical conversion of toxic emission gases. In this study, we present the fabrication of platinum and ruthenium alloy metal catalysts on the yttria-stabilized zirconia balls, and the application of the metal catalysts to the catalytic converter for methane oxidation. The platinum and ruthenium alloy metal catalysts showed better performance than the platinum catalyst, i.e., 75% increase in the methane conversion efficiency at 500℃. Such improvement seems to be because of the facile oxygen supply from the ruthenium surface. Also, the platinum and ruthenium alloy catalysts with the doped cerium oxide interlayer showed better thermal stability than the platinum and ruthenium alloy metal catalysts, possibly because of the stronger bonding between the metal and oxide support.