A solid oxide fuel cell (SOFC) comprises an ionic conducting electrolyte,a cathode and an anode.The significant reduction of SOFC operation temperature from 1000℃ to intermediate range of 600-800℃ poses serious challenges in the development of high performance electrode materials.Better electrode materials can be achieved by developing new material to overcome the present limitations or by enhancing the microstructure and electrochemical performance of the conventional fuel cell electrode materials such as lanthanum strontium manganite perovskite (LSM) cathode and Ni/Gd-doped CeO2 (Ni/GDC) cermet anodes.Here,the latest work on the nano-sized palladium particles-infiltrated Ni/Gd-doped ceria (Ni/GDC) anodes of SOFCs will be presented.The electrocatalytic effect of Pd nanoparticles on the oxidation reaction of hydrogen was investigated by electrochemical impedance spectroscopy over the temperature range of 650-900℃.The infiltrated Pd nanoparticles significantly reduce the electrode polarization resistance of the anode,and the activation energy for the electrode process associated with low frequencies decreases dramatically with the increase in the loading of Pd nanoparticles,indicating that Pd mainly promotes the adsorption and diffusion processes of the H2 oxidation reaction.XPS analysis confirms the existence of the Pd/PdOx redox couple during the H2 oxidation reaction.The significantly enhanced adsorption and diffusion processes of the H2 oxidation reaction on Pd-impregnated Ni/GDC cermet anodes are most likely due to the significantly promoted hydrogen and oxygen spillover mechanism over the nano-sized Pd/PdO redox couples,as shown schematically below.