Effect of Bi2O3 as a Sintering Aid in the Anode for Electrolyte Supported SOFC

Electrolyte-supported solid oxide fuel cells (Es-SOFCs) utilize dense electrolytes and require high sintering temperatures to enhance the interfacial properties between the electrolyte and anode. In this study, we propose the addition of a Bi2O3 sintering aid to the anode to reduce the sintering temperature of the Yttria-stabilized zirconia with 8 mol% (YSZ) electrolyte-based Es-SOFCs. The anodes of the cells consisted of NiO and GDC in a 6:4 weight ratio, with various quantities of Bi2O3. The electrochemical performance of the cells was methodically examined using current-voltage curves and constant current bias. Incorporating Bi2O3 into the anode enhanced its durability by reducing the degradation rate after 240 h of operation. Among these, the full cell with an anode containing 5 mol% Bi2O3 exhibits a better peak power density (PPD) of 0.49 W/cm2 and a PPD degradation rate of 17.6% at 800°C, compared to the cell without Bi2O3, which shows a PPD of 0.47 W/cm2 and a PPD degradation rate of 25.6%. Our results indicate that the addition of Bi2O3 as a sintering aid to an anode is an appropriate method for achieving reliable long-term stability of Es-SOFCs.