Electrical behavior of the Ruddlesden-Popper phase, (Nd0.9La0.1)2 Ni0.75Cu0.25O4 (NLNC) and NLNC- x wt% Sm0.2Ce0.8O1.9 (SDC) (x=10, 30 and 50), as intermediate-temperature solid oxide fuel cells cathode

In the present work, a new Ruddlesden-Popper phase, (Nd0.9La0.1)(2) Ni0.75Cu0.25O4 (NLNC) has been synthesized by solid state reaction for intermediate-temperature solid oxide fuel cells (IT-SOFCs) applications. The effect of sintering temperature on the microstructure and electrical properties of the NLNC cathode material is investigated. Likewise, composite cathode materials were also prepared by mixing the NLNC with 10, 30 and 50 wt% of Sm0.2Ce0.8O1.9 (SDC) powders, and firing in the temperature range of 10001300 degrees C. The crystal structure and chemical compatibility of NLNC and SDC, and their microstructures were studied by XRD and SEM, respectively. Electrical conductivity and performance of monolithic and composite electrodes as a function of the electrode composition is investigated experimentally through four probe method and electrochemical impedance spectroscopy (EIS). The results proved that no reaction occur between NLNC and SDC compounds even at a temperature as high as 1300 degrees C. Maximum total electrical conductivity of 114.36 S cm(-1) at 500 degrees C is recorded for the pure NLNC material sintered at 1300 degrees C. The polarization resistance of pure NLNC cathode was 0.43 Omega cm(2) at 800 degrees C; the NLNCSDC composite cathodes including 10, 30 and 50 wt% SDC displayed Rp value of 0.27 Omega cm(2), 0.11 Omega cm(2), and 0.19 Omega cm(2) at 800 degrees C, respectively.