Solid Oxide Fuel Cell Materials and Performance

1 Solid Oxide Fuel Cell Materials and Performance 

SOFCs are presently at the vanguard of research into a novel group of energy conversion systems because of their high efficiency, flexibility, and environmentally friendly nature. SOFCs transform the chemical energy of H2 or a hydrocarbon fuel into electric power, the exhaust being 

The Physical Chemistry of Materials Energy and Environmental Applications 

Currently, the standard SOFCs use yttria-stabilized zirconia (YSZ) (see Section 2.4.3) containing typically 8 mol% of Y02 as the electrolyte, a ceramic metal (a cermet) composed of Ni plus YSZ as the anode, and lanthanum strontium manganite (LSM) perovskite (La Sr, MnO,, ) as the cathode material [5,7,9,135], 

In an SOFC, the electrochemical reactions take place in the electrodes in the functional layer, that is, a zone within a distance of less than 10-20 pm from the electrolyte surface [5,136-138], The portion of the electrode beyond this width is principally a current collector structure, which has to be porous to permit the admission of gas to the functional layer where the oxidation and reduction reactions occur. Besides, the electrolyte has to be gas impermeable to avoid direct combination and combustion of the gases [137], The essential parts of the SOFC, that is, the electrolyte, the anode, and the cathode, are made of ceramic materials produced with appropriate electrical conducting properties, chemical and structural stabilities, similar expansion coefficients, and negligible reactivity properties [135], 

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