Modeling and prediction of structural/thermophysical properties of sintered NiO/YSZ anode for SOFC by molecular dynamics method

Anode is an important multi-functional porous cermet applied in solid oxide fuel cell. It is significant but challenging to understand co-sintering mechanism of electron-conducted NiO materials and ion-conducted (Y2O3)0.08(ZrO2)0.84 (YSZ) materials, as well as effect on the sintered structures at pore/particle scale. In the current study, an all-atom model coupled molecular dynamics simulation method is developed to capture the co-sintered NiO/YSZ porous cermet structures, as well as to evaluate effect of sintering parameters on the structural/ thermophysical properties. It is found that the initial stage of the sintering process is the major step where both the structural and thermophysical parameters change greatly. It is also captured that the effective particle stress is highly correlated with the microstructural parameters, while a high stress is mainly concentrated in the sintered necks, particle junctions and lattice boundaries. Various thermal properties are also evaluated for identifying influence of the sintering conditions. The findings obtained from this study may provide a guideline for investigating and optimizing the practical sintering parameters of the porous cermet electrodes, as well as a bottom-up approach for evaluating overall structural/thermophysical properties often applied at SOFC cell and stack studies. (c) 2023 Elsevier B.V. All rights reserved.