BaCeO3–BaCe0.8Sm0.2O3 − δ bi-layer electrolyte-based protonic ceramic fuel cell

•BaCeO3 and BaCe0.8Sm0.2O3 − δ powders were synthesized via citric-nitrate method.•BCS and BaCeO3–BCS bi-layer electrolyte-based fuel cells were fabricated.•The insertion of BaCeO3 layer could suppress formation of BaSm2NiO5 impurity.•BaCeO3–BCS bi-layer electrolyte-based fuel cell showed enhanced performance.

In this study, nano-sized BaCeO3 and BaCe0.8Sm0.2O3 − δ (BCS) powders were synthesized via citric-nitrate method. Two types of fuel cell including a BCS single electrolyte or a BaCeO3–BCS bi-layer electrolyte were fabricated using an electrostatic slurry spray deposition and their electrochemical performances were evaluated. Maximum power densities were 228 mW/cm2 and 416 mW/cm2 and the total resistances were 0.699 Ω cm2 and 0.265 Ω cm2 at 700 °C for the BCS single electrolyte and BaCeO3–BCS bi-electrolyte-based single cells, respectively. Also, the short-term stability for the cell with bi-layer electrolyte showed quite stable for ~ 24 h at a constant current loading of 450 mA/cm2 at 700 °C. Also, the performance was not decreased even after one thermal cycling.