Solid oxide fuel cell electrodes based on catalyst coatings offer substantial potential for creating improved anode and cathode structures. Infiltrated anodes based on nickel metal can yield finer catalyst phase distribution at volumetric concentrations well below percolation for traditional cermets. The coarsening of nickel after high temperature thermal treatment poses substantial degradation to the deposited structure, therefore, methods of anchoring the nickel metal to the yttria-stabilized zirconia (YSZ) scaffold have been evaluated to stabilize fine scale electro-catalyst particles. Metastable aluminum titanate was introduced into the porous YSZ anode scaffold to facilitate a step-wise chemical reaction in the formation of nickel aluminate followed by zirconium titanate to anchor the nickel metal catalyst. SEM observation of thermally treated nickel infiltrated scaffolds indicates excellent preservation of the nickel network at 800 C for 72 h. Electrochemical tests show not only decreased degradation rates, but also increased initial performance levels due to the additive.

Solid oxide fuel cell electrodes based on catalyst coatings offer substantial potential for creating more effective anode and cathode structures. Infiltrated anodes based on nickel metal can yield finer catalyst phase distribution at volumetric concentrations well below percolation for traditional cermets. The coarsening of nickel after high temperature thermal treatment poses substantial degradation to the deposited structure, therefore, methods of anchoring the nickel metal to the yttria-stabilized zirconia (YSZ) scaffold have been evaluated to stabilize fine scale electro-catalyst particles. Aluminum titanate was introduced into the porous YSZ anode scaffold to facilitate a step-wise chemical reaction to anchor the nickel metal catalyst as determined by XRD. SEM observation of thermally treated nickel infiltrated scaffolds indicates excellent preservation of the nickel network at 800 C for 72 hrs. Electrochemical tests show not only decreased degradation rates, but also increased initial performance levels due to the additive.

A simulation of a nickel‐yttrium stabilized zirconium oxide (Ni‐YSZ) solid oxide fuel cell cermet anode was used to determine the electronic current distribution within the percolating networks of nickel particles distributed in the electrode. The anode is simulated via a Monte–Carlo percolation model and current distribution is calculated via a relaxation algorithm. Nickel particle current densities are reported as a ratio to the total anode current density allowing results to be applied to any anode current density. Calculated current distributions were drastically affected by the volume percent of nickel as well as anode porosity. Experiments were performed to determine failure current densities of thin nickel wires to establish the relationship between critical current densities and surface area or volume of the wires. Both reducing and oxidizing environments were used for these measurements over a temperature range up to 800 °C.

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