Investigation of (La_1-x, Ca_x)(Ni_0.25Fe_0.25Cr_0.25Co_0.25)O₃ for solid oxide fuel cells cathode materials

In the present research, stoichiometry's of (La_1-x, Ca_x)(Fe_0.25Co_0.25Ni_0.25Cr_0.25)O₃ (x=0,0.1,0.2,0.3) (LCFCNC) were synthesized and investigated in an effort to develop a new cathode material for solid oxide fuel cells. Powders were prepared by using the polymerizable precursor method proposed by Pechini¹. X‐ray diffraction and SEM characterized the structure and morphology of the powder samples. The X‐ray diffraction results revealed the formation of single phase orthorhombic distorted perovskite structure in all the four samples. Prepared powders were made into pellets and could sinter at 1400°C for 2 hours in air. SEM analysis showed densification of the pellets with the addition of calcium. Electrical conductivity measurements on the sample were made using the AC resistance bridge between the temperature range of 100‐900°C in air. Study of electrical conductivity showed an increasing trend in electrical conductivity with respect to increase in temperature and the amount of calcium doped on A‐site from 20mol% to 30mol% and the sample with calcium 30mol% on A‐site, showed a sharp increase in electrical conductivity reaching a maximum of 50 S/cm at 800°C, demonstrating that the present materials can be used as cathode material in SOFC.