Design and Fabrication of Protonic Ceramic Fuel Cells Based on BaZr_0.8Y_0.2O_3−δ |BaZr_0.1Ce_0.7Y_0.1Yb_0.1O_3−δ Bilayer Electrolyte

Abstract

Reducing electronic leakage is important for improving the performance of protonic ceramic fuel cells (PCFCs) because it can considerably decrease power efficiency. In this work, we explore the efficacy of bilayer electrolytes using BaZr0.8Y0.2O3−δ (BZY) and BaZr0.1Ce0.7Y0.1Yb0.1O3−δ (BZCYYb) as the anode and cathode-side electrolytes, respectively. Theoretical calculations were used to guide the design and experimental fabrication of highly efficient cells. Computational results showed that higher efficiencies were achieved when a thin BZY layer was applied to a thicker BZCYYb layer. This configuration served as a barrier, effectively preventing electronic leakage. Subsequently, a BZY|BZCYYb cell was fabricated and tested using I-V and electrochemical impedance measurements. The results were compared with those of single-layer BZY and BZCYYb cells. The bilayer electrolyte exhibited higher open-circuit voltages, suggesting a reduction in the leakage current. Moreover, the bilayer cell exhibited the lowest ohmic resistance and highest power densities. Thus, bilayer electrolytes have the potential to improve the performance and efficiency of PCFCs.