Discovery and characterization of novel oxide anodes for solid oxide fuel cells

Abstract

The search for alternative anode materials for solid oxide fuel cells (SOFCs) has been reviewed in the light of structure, stability, conductivity, chemical and thermal compatibility with electrolyte YSZ. In this review, we have presented the advantages and disadvantages of the traditional Ni-YSZ anode for SOFCs. The development of alternative anode for SOFCs with fluorite, rutile, tungsten bronze, pyrochlore, perovskite and spinel structures has been reviewed and discussed in detail. Among the reported materials systems, materials with perovskite structure are promising particularly where two ions with complimentary function are present on the B-site at high concentration. We have recently found a good redox stable anode (La_0.75Sr_0.25)_1−xCr_0.5Mn_0.5O₃ (0 ≤ x ≤ 0.1) using this approach. These materials exhibit comparable performance to the traditional Ni-YSZ anode. Therefore, we can use nickel-free redox stable anode for SOFCs. With further optimisation of the composition and microstructure, the performance of these materials may be further improved and hopefully replace the traditional Ni-YSZ anode in the future. © 2004 The Japan Chemical Journal Forum and Wiley Periodicals, Inc. Chem Rec 4: 83–95; 2004: Published online in Wiley InterScience (www.interscience.wiley.com) DOI 10.1002/tcr.20003