Phase evolution and hot corrosion behavior of Yb2O3 and CeO2 co-doping YSZ ceramics under high temperature

The phase instability of 6–8 wt% Y2O3 partially stabilized ZrO2 (YSZ) in high temperature and molten salt corrosion environment seriously limits its application above 1200 °C. In this study, the chemical co-precipitation method prepared Yb2O3 and CeO2 co-doping YSZ (YbCeYSZ) ceramic materials to improve the above issues. It was proposed to improve the defect of high-temperature phase instability of CeO2-doped YSZ materials by adding Yb2O3. The phase stability, thermal insulation properties, and Na2SO4 + V2O5 molten salt corrosion behavior of YbCeYSZ ceramic materials were studied. The results showed that 2.5 mol% Yb2O3-4 mol% CeO2-YSZ material (2.5Yb4CeYSZ) had no monoclinic phase (m-ZrO2) after holding at 1500 °C for 120 h due to forming more defect clusters in the system. Meanwhile, the 2.5Yb4CeYSZ had excellent thermal insulation performance and molten salt corrosion resistance, which was attributed to the strong phonon scattering in the 2.5Yb4CeYSZ material system and the low reactivity between the stabilizer and the corrosive salt.