Strontium doped lanthanum manganite cathodes

Fig. 2 Schematic of SOFC operation presenting the four-step anodic. H2O formation and electron transfer were shown in the insert. LSM strontium-doped lanthanum manganite (cathode for SOFC), Vq" vacancy of oxygen...

Figure 4.19 Typical polarization curves for high-temperature SOFC in different gas environments at 1000° C. The high operating temperature enables the use of low-cost catalyst materials such as nickel (anode) and strontium-doped lanthanum manganite (cathode), with very low kinetic polarization losses. (Reproduced with permission from [5].)...

Fig. 13.22. The monolithic SOFC concept of Argonne National Laboratory. Anode nickel-yttria-stabilized zirconia. Cathode strontium-doped lanthanum manganite. Interconnect doped lanthanum chromite, a, Interconnection b, electron-ion path c, anode d, electrolyte e, cathode. (Reprinted from K. Kordesch,...

Strontium-doped lanthanum manganite synthesis for solid oxide fuel cells cathode. Journal of New Materials for Electrochemical Systems, Vol. 12, No. 2-3, (1 April 2009), pp. (109-113), ISSN 1480-2422... 

For the cathode, a mixture of strontium-doped lanthanum manganite (LSM) proved most suitable, and as the slurry spray process was not scalable to larger modules and production volumes, the screen printing process was chosen for the cathode fabrication [76]. 

Strontium-doped lanthanum manganite, La1 3.Sr3.MnO3 (LSM) is developed by doping lanthanum manganite with a small fraction (10%-20%) of strontium in order to enhance electronic conductivity of the cathode electrode. Lanthanum strontium cobalt ferrite (LSCF) is a mixture of lanthanum oxide, strontium oxide, cobalt oxide, and iron oxide with typical composition given as Lao eSro iCoo Fco sOs. 

For intermediate temperature SOFCs, a composite cathode consisting of strontium-doped lanthanum manganite (LSM) and YSZ has shown good performance [10]. For use with ceria-based electrolytes [11], a (La,Sr)(Co,Fe)03 (LSCF)-based cathode has been developed [12],... 

The best known type of SOFC anode-supported cells consists of a Ni/Zirconia cermet support layer, a thin functional anode, a thin dense yttria doped zirconia electrolyte layer and a thin Strontium doped lanthanum manganite (LSM) cathode layer (material alternatives are given in Fig. 8). Such cells have proved to be stable and durable for thousands of operation hours when operated at relatively mild conditions [9]. The degradation rate increases with increasing cell polarisation and increasing current density. The polarisation-dependent degradation has been identified to mainly originate from the cathode/electrolyte interface. However,... 

To ensure good contact resistance (primarily with the cathode) and minimize evaporation of chromia, many developers use interconnect coatings of strontium-doped lanthanum cobaltite or manganite, which have proven effective for at least several thousand hours. 

The anode material in SOFCs is a cermet (metal/ceramic composite material) of 30 to 40 percent nickel in zirconia, and the cathode is lanthanum manganite doped with calcium oxide or strontium oxide. Both of these materials are porous and mixed ionic/electronic conductors. The bipolar separator typically is doped lanthanum chromite, but a metal can be used in cells operating below 1073 K (1472°F). The bipolar plate materials are dense and electronically conductive. 

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