Composite electrolyte used for low temperature SOFCs to work at 390°C

Abstract

A combination of yttria stabilized zirconia (YSZ) and Ba(NO3)2 commercial powders was used as electrolytes in the construction of symmetrical SOFC. As X-ray diffraction pattern and Raman spectra revealed, the YSZ-Ba(NO3)2 electrolyte in situ converted into YSZ and yttrium-doped barium zirconate (BZY) composite at 450°C in hydrogen atmosphere. The power maximum (Pmax) of YSZ-BZY based fuel cell can reach 634.06 mW cm-2 at 450°C. Notly, the Pmax can evenly maintain at 300 mW cm-2 as the operational temperature reduced to 390°C. The outstanding cell performance at low temperature indicate the excellent ion conductivity of the composite electrolyte. The promising ion conductivity is originated from the proton conduction of BZY, the oxygen conductivity of YSZ, and the enhanced ion conduction through interface transport. Our work demonstrates that the developed YSZ-BZY electrolyte holds enormous potential for LT-SOFCs.