Modeling and evaluation of sintered microstructure and its properties for rSOFC fuel electrodes by coarse-grained molecular dynamics

• A novel bottom-up model employing CG-MD is developed to simulate the sintering process for rSOFC fuel electrode. • The microstructural and thermal-mechanical properties are evaluated. • Effects of operating conditions are investigated on the microstructural properties and internal stress. Degradation is one of the major issues affecting rSOFC (reversible solid oxide fuel cell) performance in both fuel cell and electrolysis mode operation. Defect and even damage appeared on electrode microstructure may be associated with thermal stress and strain distribution appearing in the electrode sintering process. It is necessary to investigate interactions and sintering process between material particles/clusters. A bottom-up modeling approach employing CG-MD (coarse-graining molecular dynamics) method is developed to model the sintering process for the material particles in rSOFC fuel electrodes. Based on the reconstructed porous electrode, various microstructural and thermal-mechanical properties are further evaluated for, e.g., porosity, triple-phase boundary length, and stress distribution. The effects of the material composition, sintered temperature, pressure and nanoparticle size are also investigated and discussed.