Microstructural Studies and Performance of Impregnated Manganese Containing Perovskite Solid Oxide Fuel Cell Anodes

Abstract

We report here on the development of a novel type of solid oxide fuel cell anodes that are based on Mn containing perovskites and prepared by infiltration of electrode precursor solutions into yttria stabilized zirconia scaffolds. The presence of Mn, even in small amount, on the B-site of the ABO 3 structure leads to electrode microstructures that offer a large surface area that is available for electrochemical reactions. The oxides form a remarkable thin coating on the electrode scaffold after high temperature sintering. The evolution of those films in reducing environments creates arrays of interconnected ~10nm scale particles covering the electrode scaffold. Such electrodes, based on LSCM with small amounts of added catalyst, provide outstanding performance, both for the direct oxidation of methane in solid oxide fuel cells, and the reduction of pure CO 2 in solid oxide electrolyzers.

Durability of La0.20Sr0.25Ca0.45TiO3-based SOFC anodes: identifying sources of degradation in Ni and Pt/ceria co-impregnated fuel electrode microstructures

“…12 Here, precursor solutions (typically containing nitrate salts of the desired catalyst phases) are added to the pre-sintered, porous anode microstructures to deposit coatings and particles of electrocatalyst precursors, before being calcined to form the required phases. As a result, impregnation of a wide variety of ceramic anode 'backbone' materials has been carried out, for >15 years, in both academic [12][13][14][15][16][17][18] and industrial research. 16,19,20 The A-site deficient perovskite La0.20Sr0.25Ca0.45TiO3 (LSCTA−) is a mixed ionic and electronic conductor (MIEC) material, which has shown particular promise as a replacement anode 'backbone' material for the Ni-based cermet, due to its high 'effective' electrical conductivity under reducing conditions (17 S cm -1 at 850 °C and p(O2) = 10 -19 atm), for this class of perovskite.…”