Optimization of La_0.75Sr_0.25Cr_0.5Mn_0.5O_3-δ-Ce_0.8Sm_0.2O_1.9 compositionally graded anode functional layer

A new type of anode structure, composed of a group of La_0.75Sr_0.25Cr_0.5Mn_0.5O_3-δ-Ce_0.8Sm_0.2O_1.9 (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 Ω cm² to 1.85 Ω cm² at 800°C in H₂ after introducing CGAFL. In addition, the polarization resistance further decreased to 0.30 Ω cm² 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°C. These results indicated that the CGAFL combined with the SDC interlayer may be a potential electrode structure for design optimization.