Surface decoration of Pr1.7Sr0.3Ni0.7Cu0.3O4+δ Ruddlesdene-Popper perovskite cathode with BaPrO3-δ nanoparticles by Ba doping for protonic ceramic fuel cells

The sluggish oxygen reduction reaction (ORR) at the cathode is a key step in protonic ceramic fuel cells. In this work, Pr 1.7 Sr 0.3 Ni 0.7 Cu 0.3 O 4+δ cathode with a Ruddlesden-Popper (RP) structure is modified with the doping of Ba, and BaPrO 3-δ nanoparticles are formed on the surface of the cathode. The addition of Ba improves the oxygen vacancy concentration and the electrical conductivity of the cathode, and the cathode with the nominal composition of Pr 1.7 Ba 0.15 Sr 0.3 Ni 0.7 Cu 0.3 O 4+δ shows the highest activity for the ORR process. The cathode shows the lowest polarization resistance of 0.055 Ω cm 2 at 700 °C. The hydration ability of the cathode is also enhanced with Ba. The maximum power density of a protonic ceramic fuel cell with Pr 1.7 Sr 0.3 Ni 0.7 Cu 0.3 O 4+δ cathode increases from 877 to 1262 mW cm −2 at 700 °C after the doping of Ba in the cathode. The cell also shows a promising durability.