Electrode properties of (Pr0.9La0.1)(2-x)(Ni0.74Cu0.21Al0.05)O4+delta (with x=0, 0.05, and 0.1) as cathodes in IT-SOFCs

摘要

A Ruddlesden-Popper phase, (Pr0.9La0.1)(2-x)(Ni0.74Cu0.21Al0.05)O4+delta ((PL)(2-x)NCA, x = 0, 0.05 and 0.1), is synthesized and characterized for use as a cathode material in intermediate temperature solid oxide fuel cells (IT-SOFCs). The effects of A-site cation deficiency on the thermal expansion coefficient, electrical conductivity, electrochemical properties, and thermal stability are investigated in detail. ((PL)(2-x)NCA and the Ce0.8Sm0.2O1.9(SDC) electrolyte are chemically compatible at 1000 degrees C for 5 h. The average thermal expansion coefficient (TEC) values of (PL)(2-x)NCA range from 14.1 x 10(-6)K(-1) to 14.5 x 10(-6) K-1 for temperatures between 30 and 1000 degrees C, which is close to that of conventional SOFC electrolyte materials. The (PL)(2-x)NCA samples were unstable after heating to 700 and 800 degrees C for 72 h in air. The (PL)(1.9)NCA cathode had a minimum area specific resistance (ASR) of 0.033 Omega cm(2) at 800 degrees C. When (PL)(2.)(0)NCA was used as the cathode material in electrolyte-supported single cells, the single cell reached a maximum power density of 527 mW cm(-2) at 800 degrees C using an SDC electrolyte. (C) 2019 Elsevier B.V. All rights reserved.