Improving the ionic conductivity of yttr

This study investigates the enhancement of ionic conductivity in 8 mol% yttria-stabilised zirconia electrolytes through low-temperature annealing processes prior to sintering. The objective was to identify optimal heat treatments that improve conductivity while assessing the detrimental effects of SiO2 presence in the specimens. The methodology involved applying low-temperature anneals at 1200°C for 40 hours followed by sintering at 1500°C. Extensive microstructural analyses were conducted to unravel the underlying mechanisms that contribute to conductivity enhancements. Results indicated that the heat treatment significantly improved ionic conductivity, regardless of SiO2 content, highlighting enhanced formation of coherent grain boundaries and reduced sintering strain as key factors. This research demonstrates that careful selection of heat treatments can lead to substantial improvements in the performance of yttria-stabilised zirconia ceramics in solid oxide fuel cell applications, which can ultimately facilitate the reduction of operating temperatures.