Robust Ruddlesden-Popper phase Sr 3 Fe 1.3 Mo 0.5 N i0.2 O 7-δ decorated with in-situ exsolved Ni nanoparticles as an efficient anode for hydrocarbon fueled solid oxide fuel cells

[摘要] A highly efficient Ruddlesden-Popper structure anode material with a formula of Sr 3 Fe 1.3 Mo 0.5 Ni 0.2 O 7-δ (RP-SFMN) has been developed for hydrocarbon fueled solid oxide fuel cells (HF-SOFC) application. It is demonstrated that a nanostructured RP-SFMN anode decorated with in-situ exsolved Ni nanoparticles (Ni@RP-SFMN) has been successfully prepared by annealing the anode in reducing atmosphere similar to the operating conditions. The phase compositions, valence states, morphologies, and electrocatalytic activities of RP-SFMN material have been characterized in detail. In addition, the in-situ exsolution mechanism of the metallic Ni phase from the parent oxide is clearly explained by using density function theory calculation. The peak output power density at 800°C is significantly enhanced from 0.163 to 0.409 W/cm 2 while the electrode polarization resistance is effectively lowered from 0.96 to 0.30 Ω cm 2 by the substitution of B-site Fe by Ni, which is attributed to the improved electrocatalytic activities induced by the in-situ exsolved Ni nanocatalysts. Moreover, the single cell with RP-SFMN anode exhibits good stability in 3% H 2 O humidified H 2 and syngas for 110 and 60 h at 800°C, respectively. Our findings indicate that RP-SFMN is a greatly promising anode candidate of HF-SOFCs due to its good electrochemical performance and stability during the operation.

[学科分类] 电力

[关键词] density function theory;in-situ exsolution;nanostructured anode;Ruddlesden-Popper oxide;solid oxide fuel cells