Ru/Nb co-doped perovskite anode: Achieving good coking resistance in hydrocarbon fuels via core-shell nanocatalysts exsolution

Abstract Ru/Nb co-doped (Pr0.5Sr0.5)0.9Fe0.8Ru0.1Nb0.1O3-δ (PSFRN) cubic perovskite oxide was fabricated and used as the solid oxide fuel cell (SOFC) anode material. After treated in wet H2 at 900 °C for 2 h, the PSFRN was partially transformed into Ruddlesden-Popper (RP) layered perovskite PrSrFe0.8Ru0.1Nb0.1O4+δ (RP-PSFRN), and Fe0.7Ru0.3 alloy-FeOx oxide (FRA@FO) core-shell nanoparticles were in-situ exsolved on the reduced-PSFRN (R-PSFRN) substrate surface. The phase transition and the exsolution of the nanoparticles were investigated using X-ray diffraction, transmission electron microscope and X-ray photoelectron spectroscopy. Modified by the in-situ exsolved FRA@FO core-shell nanoparticles, the R-PSFRN anode material showed high catalytic activity for hydrogen and hydrocarbon fuels. The power density of SOFC reached 0.683 and 0.537 W cm−2 with wet H2 and C3H8 as fuel at 800 °C, respectively. Moreover, the SOFC showed a stable output under a constant current load of 0.15 A cm−2 in C3H8, demonstrating a high resistance to carbon deposition and coking.