PrBa0.5Sr0.5Co2O5+x as cathode material based on LSGM and GDC electrolyte for intermediate-temperature solid oxide fuel cells

Abstract

PrBa0.5Sr0.5Co2O5+x (PBSC) oxides have been evaluated as cathode materials for intermediate-temperature solid oxide fuel cells (IT-SOFCs) with Ce0.9Gd0.1O1.95 (GDC) and La0.9Sr0.1Ga0.8Mg0.2O3−δ (LSGM) as electrolytes. XRD results show that PBSC cathode is chemically compatible with the intermediate-temperature electrolyte materials GDC and LSGM. The maximum electrical conductivity is 1522 S cm−1 at 100 °C and its value is higher than 581 S cm−1 over the whole temperature range investigated. Microstructures show that the contact between PBSC and LSGM is better than that between PBSC and GDC. The area-specific resistances (ASRs) of PBSC cathode on GDC and LSGM electrolytes are 0.048 and 0.027 Ωcm2 at 800 °C, respectively. The electrolyte-supported (thickness of electrolyte is 300 μm) fuel cells generate good performance with the maximum power densities of 617 mW cm−2 on GDC electrolyte and 1021 mW cm−2 on LSGM electrolyte at 800 °C. All results demonstrate that PBSC oxide is a very promising cathode material for application in IT-SOFCs and this cathode based on LSGM electrolyte obtained better performance than on GDC electrolyte.