Suppressed Carbon Deposition Behavior in Nickel/Yittria-Stablized Zirconia Anode with SrZr[sub 0.95]Y[sub 0.05]O[sub 3−α] in Dry Methane Fuel

The distribution of carbon deposition on the cross section of a nickel/yittria-stablized zirconia (Ni/YSZ) anode after an accelerated degradation test in dry methane was analyzed using a scanning electron microscope equipped with an energy dispersive X-ray. The area near the anode top surface side was favored for carbon deposition compared with that near the electrolyte side, suggesting that the electrochemically produced and oxygen near the triple phase boundary near the anode top surface side were insufficient for carbon removal reaction. To enhance the reaction of carbon with these two species, a proton-conductor (SZY) was used to modify the Ni/YSZ anode by the infiltration method. The Ni/YSZ anode infiltrated with SZY (Ni/YSZ–SZY) showed a unique structure in which the distribution of SZY was mainly localized near the anode top surface side. In conclusion, the modification of the Ni/YSZ anode by the addition of the proton-conductor SZY improved the operational stability of the anode in dry methane.