Properties of La2-xPrxNiO4 cathode for intermediate-temperature solid oxide fuel cells

Abstract

A series of K2NiF4-type compounds, La 2-xPrxNiO4 (x = 0, 0.6, 1.0, 1.4, and 2.0), were synthesized by solid state reaction for use as cathodes in an intermediate-temperature (500700° C) solid oxide fuel cell (IT-SOFC). La2-xPrxNiO4 (x = 0 and 0.6) crystallize in the Fmmm space group, while La2-xPrxNiO4 (x = 1.0, 1.4, and 2.0) belong to the Bmab space group. The electrical conductivity increased by Pr doping and La2-xPrxNiO4 (x = 0.6, 1.0, and 1.4) exhibited electrical conductivities similar to one another while Pr2NiO4 had the highest. Single test-cells consisting of samarium oxide doped ceria (SDC) as an electrolyte, NiSDC cermet as an anode and La2-xPrxNiO4 as a cathode, were fabricated for measurements of cell performance at 500700° C. Current interruption measurements revealed that the overpotential losses mainly decreased with increasing Pr content. Pr2NiO4 was found to exhibit the best cathode characteristics; maximum test-cell power densities of 14.1, 45.1, and 104.4mW/cm2 were obtained at 500, 600, and 700°C, respectively. © 2011 The Ceramic Society of Japan.