稀土氧化铈复合陶瓷材料具有优异的性能，广泛应用于固体电解质、催化剂、抛光粉、电极等材料。由于氧化铈具有三价和四价不同价态存在形态，在氧化和还原气氛中发生相变，伴随相变产生热效应和体积变化以及组织结构变化，并对其热性能、催化性能、电化学性能等产生影响。因此，系统研究氧化铈相变及其对性能的影响，对拓展氧化铈陶瓷材料的应用领域非常必要。本项目拟选取钐、钆氧化物等掺杂剂，制备掺杂氧化铈复合陶瓷固态电解质材料，采用热分析、XRD、热机械分析、阻抗分析以及电镜等方法和技术研究氧化铈相变规律，确定氧化铈体系的热力学平衡状态和可能的中间相存在条件；测定分析相变过程的热效应、体积变化，探索其对材料性能和电池性能的影响；利用空气、氧气、氢气和氩气等介质改变环境气氛，研究氧化、还原及惰性气氛中掺杂氧化铈电解质的相变规律。获得掺杂氧化铈的物理化学性能与相变的关系，为掺杂氧化铈的应用提供理论和实验基础。

CeO2 composite ceramic has been used as solid electrolyte, catalyst, polishing and electrode materials because of its superiority properties. The phase transformation is carried through because of Ce+3/Ce+4 states in oxidation or reductive atmosphere.The thermal effect, geometric dimension and structure change with the phase transformation of doped CeO2,which result in the changes of thermal properties, catalyst, electrochemical properties. It is an important to research the phase transformation and the ralations of the properties of doped CeO2 with the phase transformation.In this work, CeO2 composite ceramic electrolyte doped with Sm, Ga will be synthesized. The phase transformation of doped CeO2 ceramics in different atmosphere is investigated。The changes of the thermal effect, geometric dimension and structure and properties of samples are measured. The relations of the properties of doped CeO2 composite ceramic electrolyte with doping elements, temperature, atmosphere are studied. The relatonship of the physical chemistry properties of doped CeO2 composite ceramic electrolyte with phase transformation are acquired.