La0.8Sr1.2CoO4+δ-CGO composite as cathode on La0.9Sr0.1Ga0.8Mg0.2O3−δ electrolyte for intermediate temperature solid oxide fuel cells

► LSCO4 oxide is chemically compatible with CGO and LSGM electrolyte at 1100 °C. ► A low electrode polarization resistance of 0.21 Ω cm2 is achieved at 750 °C. ► The low ASR exhibits high electrochemical activity at intermediate temperature range. ► The single cell shows a maximum cell power density of 515 mW cm−2 at 750 °C. ► The LSCO4-CGO composite oxides are one of promising cathode candidates for IT-SOFCs.