TEMPERATURE AND PREASSURE ASSISTED CUBIC TO RHOMBOHEDRAL PHASE TRANSITION IN Sc_(0.1)Ce_(0.01)ZrO_2 BY MICRO-RAMAN

摘要

It was recently shown that the high temperature cubic Sc_(0.1)Ce_(0.01)ZrO_2 is metastable at room temperature and could be easily transformed to the thermodynamically stable rhombohedral phase upon annealing at 350℃-400℃ after a certain period of time. Such transition, though not drastically important for operation of Intermediate Temperature Solid Oxide Fuel Cell, still might degrade the performance of Sc_(0.1)Ce_(0.01)ZrO_2 electrolyte upon thermal cycling. Therefore, the properties of the cubic and rhombohedral Sc_(0.1)Ce_(0.01)ZrO_2 phases have to be studied. Here, we report the vibration response of cubic and rhombohedral Sc_(0.1)Ce_(0.01)ZrO_2 studied both at room and high-temperatures. Stress and temperature-assisted phase transition from cubic to rhombohedral phase was detected during in-situ Raman spectroscopy experiments. The conditions which promote either the formation of rhombohedral phase or retention of cubic phase upon temperature or stress applications have been determined.