A polymer complex solution process for the synthesis and characterization of Ni–YSZ cermet material

Ni–YSZ cermets for SOFC anodes were prepared by the Pechini-type reaction route. The initial polymer precursors were prepared with different citric acid/ethylene glycol (CA/EG) molar ratios. The properties of the samples at different stages of the preparation procedure were evaluated with regard to thermal decomposition (TG–DTA), crystallite size (XRD), surface area (BET), sinterability and phase distribution (SEM). The results showed that an increase of CA and EG in the starting solution increased the final temperature of the thermal decomposition of gels from 340 °C to 382 °C, and the specific surface area of calcined NiO–YSZ powders from 10 m2 g−1 to 27 m2 g−1. In parallel the sinterability of the samples increased. A distinct increase of CA in the predominantly aqueous solution diminished the nickel grain size in the final Ni–YSZ material. A shift from aqueous to organic media further reduced the nickel-rich regions to around 0.2 μm.