Ni-Fe nanoparticles are observed to exsolve from Ni-substituted Sr 0.95 (Ti 0.3 Fe 0.63 Ni 0.07 )O 3Àd anode. The exsolved nanoparticles act to enhance hydrogen dissociative adsorption, yielding much lower anode polarization resistance and higher cell performance, especially under low pH 2 and temperatures, which is comparable with the current Ni-based cermets.

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10% Ni-doped Sr 2 Fe 1.5 Mo 0.5 O 6-δ with A-site deficiency is prepared to induce in situ precipitation of B-site metals under anode conditions in solid oxide fuel cells. XRD, SEM and TEM results show that a significant amount of nano-sized Ni-Fe alloy metal phase has precipitated out from Sr 1.9 Fe 1.4 Ni 0.1 Mo 0.5 O 6-δ upon reduction at 800 • C in H 2 . The conductivity of the reduced composite reaches 29 S cm −1 at 800 • C in H 2 . Furthermore, fuel cell performance of the composite anode Sr 1.9 Fe 1.4 Ni 0.1 Mo 0.5 O 6-δ -SDC is investigated using H 2 as fuel and ambient air as oxidant with La 0.8 Sr 0.2 Ga 0.87 Mg 0.13 O 3 electrolyte and La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3 cathode. The cell peak power density reaches 968 mW cm −2 at 800 • C and the voltage is relatively stable under a constant current load of 0.54 A cm −2 . After 5 redox cycles of the anode at 800 • C, the fuel cell performance doesn't suffer any degradation, indicating good redox stability of Sr 1.9 Fe 1.4 Ni 0.1 Mo 0.5 O 6-δ . Peak power density of 227 mW cm −2 was also obtained when propane is used as fuel. These results indicate that a self-generated metal-ceramic composite can been successfully derived from Sr 2 Fe 1.5 Mo 0.5 O 6-δ by compositional modifications and Sr 1.9 Fe 1.4 Ni 0.1 Mo 0.5 O 6-δ is a very promising solid oxide fuel cell anode material with enhanced catalytic activity and inherited good redox stability from the parent ceramic material.