Transport Properties of Composite Cathode Materials La0.8Sr0.2Fe0.7Ni0.3O3 - Оґ/Ce0.9Gd0.1O1.95
YU. S. OKHLUPIN and N. F. UVAROV
Institute of Solid State Chemistry and Mechanochemistry, Siberian Branch of the Russian Academy of Sciences
ohlupin@mail.ru
Keywords: relaxation of electrical conduction, composites La0.8Sr0.2Fe0.7Ni0.3O3 -Оґ/ Ce0.9Gd0.1O1.95, oxygen diffusion, oxygen exchange, cathode materials
Pages: 311–314
Abstract
Full conductivity, diffusion and oxygen exchange properties in the composites (100 - х)La0.8Sr0.2Fe0.7Ni0.3O3 -δ/xCe0.9Gd0.1O1.95 (LSFN/CGO, x - volume fraction, 0 < x < 71.1 %) were studied by means of the relaxation of electrical conduction at 700 °C for partial oxygen pressure within the range (0.2–3) · 10-3 atm. It was demonstrated that the electric conduction of the composites decreases monotonously with an increase in the concentration of CGO, while the coefficient of the chemical diffusion of oxygen (Dchem ) increases. The constant of oxygen exchange (kchem ) is higher for composites than for individual phases LSFN and CGO. The dependence of kchem value on the composition of the composite may be due to the effect of interphase boundaries on oxygen exchange processes. The total efficiency of oxygen transport in LSFN/CGO composites at a temperature of 700 °C is maximal for the composites with the volume fraction of CGO close to 70 %.
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