Electrochimica Acta, Vol.152, 155-160, 2015
Optimization of La0.75Sr0.25Cr0.5Mn0.5O3-delta-Ce0.8Sm0.2O1.9 compositionally graded anode functional layer
A new type of anode structure, composed of a group of La0.75Sr0.25Cr0.5Mn0.5O3-delta-Ce0.8Sm0.2O1.9 (LSCM-SDC) compositionally graded anode functional layers (CGAFL) and a porous SDC interlayer adjacent to the electrolyte, was fabricated by screen printing method for intermediate-temperature solid oxide fuel cells (IT-SOFCs). The results of electrochemical impedance spectroscopy (EIS) show that the polarization resistance decreased from 3.49 Omega cm(2) to 1.85 Omega cm(2) at 800 degrees C in H-2 after introducing CGAFL. In addition, the polarization resistance further decreased to 0.30 Omega cm(2) when the CGAFL combined with the SDC interlayer, demonstrating a reduction by factors of 11.6 and 6.2, respectively, compared with the non-graded cell and the CGAFL cell without the SDC interlayer. The single cell displayed that the CGAFL combined with the SDC interlayer increased the maximum power density by factors of 2.9 and 2.1, respectively, at 800 degrees C. These results indicated that the CGAFL combined with the SDC interlayer may be a potential electrode structure for design optimization. (C) 2014 Elsevier Ltd. All rights reserved.
Keywords:Solid oxide fuel cell;Compositionally graded anode;Ceria-based interlayer;Electrochemical impedance spectroscopy;Single cell performance