Alloying effects of Pd and Ni on the catalysis of the oxidation of dry CH 4 in solid oxide fuel cells

Abstract

The mechanisms of Ni, Pd and Pd-Ni catalysts in a solid oxide fuel cell (SOFC) were studied to clarify the alloying effects of Pd and Ni on the catalysis for the oxidation of CH 4 fuel. Pd-Ni and Pd catalysts loaded on a composite anode of La 0.8Sr 0.2CrO 3 (LSCr) and Ce 0.8Sm 0.2O 1.9 (SDC) show catalytic activity for the oxidation of CH 4. The impedance study for these anodes clearly suggests a difference between the reaction mechanisms on the Pd–Ni/and the Pd/LSCr–SDC anodes. The dominant reaction path for the methane activation seems to be a non-electrochemical process on the Pd-Ni catalyst, whereas the activation of CH 4 over the Pd catalyst occurs only on electrochemically active sites.