Performance and DRT analysis of infiltrated functional cathode based on the anode supported SOFCs with long-term stability

Abstract

Designing cathode functional layer (CFL) to accelerate oxygen reduction reaction (ORR) is widely studied. However, the relationship between morphology and ORR kinetic of CFL need to be in-depth studied. Here, a highly efficient and robust La0·6Sr0·4CoO3 (LSC) CFL is prepared into Ce0.9Gd0.1O1.95 (GDC) scaffold in a commercial anode supported half-cell by infiltrating method, which exhibits remarkably enhanced ORR activity, compared with the traditional LSC CFL fabricated by mechanical mixing LSC-GDC. As a proof, the infiltrated LSC CFL based single SOFC delivers a maximum power density of 1.2 W cm−2 at 750 °C and an excellent long-term stability with a voltage attention rate of 0.058%/100 h at 0.5 A cm−2 for 550 h. The distribution of relaxation times (DRT) method is introduced to understand improved electrochemical performances. Optimized porosity, extend three phase boundary and shorted charge transfer path change the rate-determining step in the infiltrated CFL cell.