Abstract
Solid oxide fuel cell (SOFC) systems provide an alternative electricity production source, with potentially zero carbon emissions. In order to decrease the chemical and mechanical degradation in its components, operation temperature of SOFCs must be lowered. However, transport phenomena required for SOFC adequate operation are temperaturedependent. Therefore, new materials must be devised to compensate for the temperature decrease. This paper reviews the state-of-the art on SOFCs devices and materials intended for operation below 700 °C, named intermediate temperature (IT)-SOFCs. Current research developments on electrolyte, cathode and anode materials are reviewed. Emphasis on the critical issues of cathode/electrolyte half-cell is made. The relatively recent LSCF/CGO system has shown promising polarization resistance behavior, reaching 0.13 Ω.cm2 at 600 °C, and is often contrasted to the conventional LSM/YSZ combination. The oxygen reduction reaction mechanism and interconnect materials are also reviewed. Electrostatic spray deposition is highlighted as a promising film deposition technique, able to produce a large variety of oxide film microstructures by controlling a few deposition parameters. One of the advantages is the ability to obtain large surface area films due to the arrangement of nano-sized solid particles.
Keywords: Review, SOFC, La0.6Sr0.4Co0.2Fe0.8O3-δ, LSCF, electrostatic spray deposition, ESD, Ce0.9Gd0.1O2-δ, CGO, impedance spectroscopy
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