利用高压原位拉曼光谱技术研究了非静水条件对CeO2纳米八面体高压结构相变的重压影响。研究表明: 在非静水条件下(无传压介质), 当压力达到26 GPa时, CeO2纳米八面体发生由立方萤石型结构到正交α-PbCl2型结构的可逆结构相变, 相变压力低于相应的体材料(30 GPa)。相反, 在准静水压条件下, CeO2纳米八面体的相变压力为33 GPa, 高于其体材料。研究表明, 实验条件对CeO2纳米八面体结构稳定性具有重要影响。

The effect of nonhydrostatic conditions on high pressure phase transition on CeO2 nano-octahedrons were studied using in situ high-pressure Raman spectroscopy. Under non-hydrostatic conditions (with no pressure medium) the CeO2 nano-octahedrons underwent a reversible phase transition from fluorite phase to α-PbCl2 phase at 26 GPa, which is lower than the bulk counterpart. In contrast, the CeO2 nano-octahedrons under hydrostatic conditions are shown to be more stable than the bulk. The transition pressure from cubic to orthorhombic phase is approximately 3 GPa higher than bulk materials. These results show that experimental conditions have an important effect on the structural stability of CeO2 nano-octahedrons.