Journal of the American Ceramic Society, Vol.88, No.11, 3215-3217, 2005
Stability of channeled Ni-YSZ cermets produced from self-assembled NiO-YSZ directionally solidified eutectics
Channeled yttria-stabilized cubic phase of the zirconia (Ni-YSZ) cermets are produced by reduction of laser-assisted directionally solidified NiO-YSZ lamellar eutectics. The material is formed by similar to 400 nm wide alternating lamellae of 40% porous Ni and YSZ, which serve as parallel channels for gas flow and electronic transport and for oxygen ion diffusion. The low-energy interfaces formed between the metallic Ni particles and the YSZ prevent particle coarsening and impart long-term stability to the anode at operating temperatures. The electrical conductivity and the pore size distribution present no degradation after 300 h at 900 degrees C under a H-2/N-2 atmosphere. This stability is indicative of an improvement in comparison with conventional Ni-YSZ anodes for solid oxide fuel cells.