Physical characterization of Y0.25Zr0.60Ti0.15O2−x and its performance as a Ni/Y0.25Zr0.60Ti0.15O2−x anode cermet in an SOFC

The physical properties of the ceramic Y0.25Zr0.60Ti0.15O2−x (YZT) and Ni/YZT cermets are presented and evaluated in terms of an application as anode substrate or anode material in solid oxide fuel cells (SOFC). Cermets with different Ni content were exposed at 1000 °C for up to 1000 h and showed a better long-term stability in terms of electrical conductivity and microstructure than cermets with yttria (8 mol%)-stabilized zirconia (Ni/8YSZ). This is explained by the different bonding strength at the Ni/ceramic interface due to the Ti content. In contrast to the superior behavior as an anode substrate, the electrochemical performance of a Ni/YZT anode is significantly lower than a Ni/8YSZ anode. The reason here is most likely the reduced ionic conductivity of YZT, which is about one order of magnitude smaller than that of 8YSZ.