Synthesis of bismuth-doped yttria-stabilized zirconia electrolyte and study of ionic conductivity

BiYSZ, a Bi3+-doped yttria-stabilized zirconia with 4% molYO1.5, was synthesized using a lamellar liquid crystal template technique. The influence of different doping amounts of Bi3+ on crystal form, morphology and the ionic conductivity has been investigated in detail. In addition, the densification time of BiYSZ has been determined. Analytical techniques such as X-ray diffraction (XRD), Raman spectroscopy and scanning electron microscopy (SEM) have been utilized to characterize the synthesized powders. The results reveal that BiYSZ, with its stable tetragonal phase and spherical nanostructure, benefits from Bi3+ doping in 4% mol YO1.5-stabilized zirconia, leading to enhanced ionic conductivity. Notably, the optimal formulation with 3 mol% Bi3+ and 4 mol% Y3+ in yttria-stabilized zirconia reaches a maximum ionic conductivity of 7.41 × 10−5 S/cm at 500°C. This formulation also reduces the sintering temperature by 100°C compared to 4YSZ and significantly improves conductivity by an order of magnitude.