Dependence of Electrochemical Performance on Microstructure and Distribution for Ni/YSZ Anode with Y-doped BaZrO_3 in Solid Oxide Fuel Cells

摘要

Distribution of proton conductor yttrium-doped barium zirconate (BZY) within a nickel (Ni)/yttria-stabilized zirconia (YSZ) anode was controlled using composite powder prepared by spray pyrolysis, and the dependence of electrode performance on this BZY distribution within the Ni/YSZ anode was investigated to clarify the role of BZY in improving the anode performance when humidified hydrogen or dry methane is the fuel. First, the effective thickness of the Ni/YSZ anode electrochemical reaction was determined, and then BZY was distributed to either the inside or the outside of the effective thickness. The BZY addition inside the effective thickness improved the anode performance and, in contrast, the BZY addition outside did not improve the anode performance, suggesting that the role of BZY is mainly to promote the electrochemical reactions occurring within the effective thickness.