Synthesis and characterization of a Ni/Ba2In0.6Ti1.4O5.7□0.3 cermet for SOFC application

Ni-based cermets were prepared and reduced from mixtures of NiO and Ba2In0.6Ti1.4O5.7□0.3. A cermet containing 18.7 vol.% of Ni exhibits promising characteristics: 40% of open porosity and a lower DC resistivity than a Ni/YSZ cermet with a larger Ni content (30 vol.%). Its thermal expansion coefficient is 11.4 × 10− 6 K− 1 whereas that measured for Ba2In0.6Ti1.4O5.7□0.3 is 9.9 × 10− 6 K− 1. Electrical measurements vs. the Ni content have shown that the percolation threshold corresponds to 15.7 vol.% of Ni. By using saccharose as a pore former, the porosity of the electrode can be tuned. It is shown that the pore size is controlled by the particle size distribution of the pore former.