Metal-supported solid oxide fuel cells get progress—High-active nano ceria anode materials

Solid oxide fuel cells (SOFCs) electrochemically convert fuels such as hydrogen and methane into electricity in an energetically efficient and environmentally friendly manner and have great application prospect in the lager power station, distributed power station, combined heat and power (CHP) system and on-board auxiliary power unit (APU). However, due to the cost and longevity issues, SOFC techniques have not got large-scale applications. In the last few years, novel metal-supported solid oxide fuel cells (MS-SOFCs) have gained increasing interest for the advantages like excellent structural robustness and stability, high tolerance toward rapid thermal cycling, easy stack assembling as well as low materials cost. However, due to the unique characteristics of metal materials, employing alloys, e.g., stainless steel as the support may bring a number of challenges to the cell fabrication and operation processes.

Zhan Zhongliang from Shanghai Institute of Ceramics, Chinese Academy of Sciences (SICCAS) and his cooperator prepared the Nano-SDC@430L anode by infiltrating the nano Sm0.2Ce0.8O2-δ(SDC) into the inside of the macro-porous 430L stainless steel scaffolds. Nano-SDC@430L anode demonstrated excellent catalytic activity for hydrogen electro-oxidation and showed polarization resistances as low as 0.10±0.01 and 0.18±0.03 Ω cm2 at 800 and 700 °C, respectively. This is enabled by superior redox properties of ceria catalysts and high conductivities of the supporting 430L scaffolds. Thin yttria-stabilized zirconia electrolyte fuel cells with such anodes produced promising power densities of 0.94 W cm-2 at 800 °C and 0.55 W cm-2 at 700 °C. This structure design not only solves the anode preparation issues of cell anode for MS-SOFCs but also provides a new approach to make high-active anodes. Related research results have been published in Adv. Energy Mater.

This work is supported by the 973 National Basic Research Program of China, the 863 Chinese Government High Tech Developing Project and the National Science Foundation of China.