In situ exsolved NiFe nanoparticles in Ni-doped Sr_0.9Ti_0.3Fe_0.63Ni_0.07O_3‑δ anode with a three-dimensionally ordered macroporous structure for solid oxide fuel cells fueled by alkanes

In this work, A-site deficient Ni-doped Sr_0.9Ti_0.3Fe_0.63Ni_0.07O_3‑δ perovskite anode with ordered macroporous structures (STFN-3DOM) is designed to facilitate in-situ Ni-Fe exsolution for solid oxide fuel cells fueled by alkanes, e.g., methane and propane. The large specific surface area and A-site deficient of STFN-3DOM provide more exsolved Ni-Fe active sites and enhance the reaction kinetics of alkane reforming. Quasi-in-situ XPS is used to reveal the changes in the chemical state of elements during the exsolution and propane reforming process on the STFN-3DOM surface. The synergistic effect of A-site deficient, three-dimensional ordered macroporous structure, and in-situ Ni-Fe exsolution promotes the La_0.8Sr_0.2Ga_0.83Mg_0.17O_3‑δ (LSGM) electrolyte-supported SOFC single cell to deliver advanced performance with both wet H₂ (1.33 W cm⁻²) and wet C₃H₈ (0.838 W cm⁻²) at 850 °C, exhibiting satisfactory long-time stability in CH₄ and redox stability. Density functional theory calculation confirms the low activation energy of STFN-3DOM for the rate-limiting step of C₃H₈* dissociation.