Effects of material fabrication and current collector on the total conductivity of doped barium zirconates

Doped barium zirconates (BaZrO 3 ) are predominantly employed in protonic ceramic fuel cells and electrolysis cells. Electrochemical impedance spectroscopy (EIS) has been utilized to determine the total conductivity ( σ tot ) of these materials. However, significant variations in σ tot of doped BaZrO 3 protonic ceramic electrolytes have been observed depending on materials fabrication processes and current-collecting materials. This study reviews how the fabrication process can influence the microstructure and physical characteristics of the final sintered doped BaZrO 3 electrolytes, consequently their σ tot . Symmetric cells were fabricated using BaZr 0.8 Y 0.2 O 3-δ (BZY20) electrolyte with different current-collecting materials (Pt, Ag, and Ni) as electrodes, and varying σ tot values were measured. The results were analyzed to identify primary and secondary factors contributing to the observed variations. Finally, this study proposes pathways to minimize the discrepancies in σ tot arising from materials fabrications and current-collecting materials. • Discrepancies in the total conductivity ( σ tot ) of doped barium zirconates were identified. • The impact of material fabrication processes on variations in σ tot was reviewed. • The electrical resistivity and contact resistance were identified as primary factors in current-collecting materials, contributing to the discrepancies in σ tot . • The influence of porosity and melting point of current collector was discussed as a minor factor.