Deep oxidation of methane on particles derived from YSZ-supported Pd–Pt-(O) coatings synthesized by Pulsed Filtered Cathodic Arc

Methane total oxidation was studied between 250 and 800 °C in a specific quartz reactor for Pd, PdOy, Pd0.6Pt0.4Oy and Pd0.4Pt0.6Oy thin films deposited on yttria stabilized zirconia (YSZ) substrates. Pt containing films exhibited poor activity and a rapid thermal decomposition. Pd and PdOy films showed good activity and transformed to particles dispersed on the YSZ substrates. The higher reaction rate of PdOy films was explained by a better dispersion of the catalyst. A drop of the reaction rate was observed when the temperature exceeded 735 °C and 725 °C for initially Pd and PdOy, respectively, which can be associated with the decomposition of PdO into Pd and O2. The good cycling stability and catalytic efficiency of the latter films render it promising for the pollution control in methane combustion.