Coarse-grained molecular dynamics investigation of nanostructures and thermal properties of porous anode for solid oxide fuel cell

Incorporation of nanoscale catalysts into porous structures of SOFC has been proven highly successful in increasing active sites and catalyst utilization. In addition, electrochemical reactions as well as heat transfer process in porous anode are strongly affected by complex porous structures. It is believed that study of anode thermal properties are critical for SOFC design and operation. In this work, an AA model is developed for nickel and YSZ components via ASE, and a CG technique is further applied to represent Ni and YSZ beads by VMD, which are then self-assembled to capture the anode nanostructure via GROMACS. LAMMPS is then employed to evaluate average thermal properties of the porous anode. It is found that, at low Ni content (≤30 vol%), thermal conductivity increases with increasing temperature due to lattice vibrations. Instead, the anode exhibits metallic behavior due to rich nickel phase. Thermal expansion of the anode increases with increasing nickel content. Average thermal properties of the anode are validated by open literature data with good agreement. This approach is considered to be applied to analyze nanostructures, heat transfer and temperature distribution in the porous anode, and is also useful to capture thermal performance of SOFC and stack.