Sr1-xCaxMoO3-Gd0.2Ce0.8O1.9 as the anode in solid oxide fuel cells: Effects of Mo precipitation

JOURNAL OF ALLOYS AND COMPOUNDS

卷:587

Article

Xiao, Peng¹  Ge, Xiaoming²  Liu, Zhaolin²  Wang, Jing-Yuan³  Wang, Xin¹ 

[1] Nanyang Technol Univ, Sch Chem & Biomed Engn, Singapore 639798, Singapore

[2] ASTAR, IMRE, Singapore 117602, Singapore

[3] Nanyang Technol Univ, Residues & Resource Reclamat Ctr, Singapore 639798, Singapore

关键词: Solid oxide fuel cells;    Strontium molybdate;    Calcium doping;    Mo segregation;    Perovskite;   

DOI  :  10.1016/j.jallcom.2013.10.187

来源: Elsevier

【 摘 要 】

Calcium is incorporated into strontium molybdate to form Sr1-xCaxMoO3 as an electronic conductor for solid oxide fuel cells (SOFCs). Metallic molybdenum was observed with the increasing content of Ca substitution for Sr in Sr1-xCaxMoO3. Rietveld refinement reveals the phase transition from cubic to tetragonal perovskite structure, which implies its decreased thermodynamic stability under reducing conditions with increasing content of Ca. X-ray diffraction (XRD) and differential scanning calorimetry-thermogravimetric analysis (DSC-TGA) further prove that this Mo ex-solution is reversible. The electrochemical performances of Sr1-xCaxMoO3 towards H-2 and CH4 oxidation at 800 degrees C are examined. The performance is improved in H-2 atmosphere with the introduction of Ca, 330mWcm(-2) of Sr0.5Ca0.5MoO3-Gd0.2Ce0.8O1.9 (GDC) vs. 280mW cm(-2) of Sr1-xCaxMoO3, which can be ascribed to the segregated Mo as the additional catalyst. However, carbon deposition is observed after exposure to CH4 at 800 degrees C for both Sr1-xCaxMoO3-GDC and Sr1-xCaxMoO3, in contrast to the absence of carbon on Sr1-xCaxMoO3-GDC. 2013 Elsevier B. V. All rights reserved.

【 授权许可】

Free