New oxide cathodes and anodes

Abstract

Many of the key issues facing solid‐oxide fuel cell (SOFC) technology development may be addressed by finding improved electrode materials. These include lower temperature of operation, fuel flexibility, and sulfur and chromium tolerance. Here we review recent advances in anode and cathode materials design, focusing particularly on perovskite materials and their ordered structures, including intergrowths. Materials discovery, synthesis, fabrication, and evaluation are discussed. Particular emphasis is given to design of multifunctional composites at the nano‐ and microscales.

Stabilization of a Complex Perovskite Superstructure under Ambient Conditions: Influence of Cation Composition and Ordering, and Evaluation as an SOFC Cathode

“…A site cation and oxygen vacancy ordering are directly linked to the transition metal environment and oxidation state, and have a dramatic influence on the targeted behavior of the compounds. − Control of these features can therefore be of crucial importance for the generation of interesting new properties. One important application area is in solid oxide fuel cell (SOFC) cathodes − − in an SOFC, the cathode is responsible for the catalysis of the reduction of the dioxygen O 2 molecule to O 2− and must be a mixed electronic conductor (to deliver electrons liberated from the fuel at the anode to reduce O 2 ) and ionic conductor (to transport the generated oxide ions via the electrolyte to the anode for fuel oxidation) stable in an oxidizing atmosphere. Transition metal oxides are thus the appropriate materials class for this application.…”

Energy, Environment and IMCC

“…A main advantage of the SOFC compared to other fuel cells is its fuel flexibility. This means that hydrocarbons, which have the highest energy density of all practical chemical compounds for energy storage, can be converted in an SOFC, either via steam reforming on the Ni containing zirconia cermet of the classical SOFC or by direct conversion in SOFC types, which are under development (3). Most of the SOFC literature is in some way, directly or indirectly, about IMCC.…”

“…Recent years' research has pointed towards even more complicated multiphase structures such as dual phase composites of micron sized particles with porosities impregnated with nanoparticles. Sometimes, nanoparticles are of the same material as one of those constituting the electrode composite (3,4). The nanoparticles may improve the electrode performance by an order of magnitude (5,6).…”