A cobalt-free Sm0.5Sr0.5Fe0.8Cu0.2O3−δ-Ce0.8Sm0.2O2−δ composite cathode for proton-conducting solid oxide fuel cells

▶ The quad-layer single cells of NiO-BZCYYb/NiO-BZCYYb/BZCYYb/SSFCu-SDC show an excellent power density of 505 mW cm−2 at 700 °C. ▶ A low electrode polarization resistance of 0.138 Ω cm2 is achieved at 700 °C, which exhibits high electrochemical activity for operation at intermediate temperature range. ▶ The XRD spectrum of the SSFCu-SDC composite cathode indicates an excellent chemical compatibility between SSFCu and SDC at temperatures up to 1100 °C. ▶ Adding Ce0.8Sm0.2O2−δ (SDC) electrolyte which is widely used for SOFCs based on SDC oxide ion conductors, into SSFCu cathode to prepare the composite cathode for H-SOFCs. Preliminary results demonstrate that the cobalt-free SSFCu-SDC composite is a promising cathode material for H-SOFCs.