不同合成条件对CePO_4形貌和晶相的影响（英文）

Influences of Synthesizing Conditions on the CePO_4 Morphology and Phase Form

采用化学沉淀法对合成的CePO4前驱体进行了研究,探讨了不同合成试剂制备的CePO4前驱体随煅烧温度变化晶体的相变情况。TEM和SEM结果显示,H3PO4溶液和CeCl3溶液在室温下合成产物呈针状,而Na3PO4溶液和CeCl3溶液室温下的合成产物为胶状。差热-热重分析(TG-DTA)和XRD实验结果表明,H3PO4溶液和CeCl3溶液合成产物在711.5℃时发生相变,由六方晶相转变为单斜晶相,而Na3PO4和CeCl3的合成产物在231℃时会发生相变,由无定形态转变为单斜晶相。

The synthesis of precursor of cerium phosphate（ CePO4） by the chemical precipitation method was studied. The effects of different reagents and calcining temperatures on the phase form of products were investigated. The analyses using transmission electron microscopy（TEM） and scanning electron microscopy（SEM）,showed that the morphology of preliminary products was needle-like synthesized by H3PO4 and CeCl3and colloidal by Na3PO4 and CeCl3at room temperature. Both results of TG-DTA（the thermal gravimetric and differential thermal analysis）and XRD indicate,that the phase form of precursor of CePO4 synthesized by H3PO4 and CeCl3change from hexagonal phase to monoclinic phase at about 711. 5 ℃ and from amorphous state to monoclinic phase at about 231℃ when the precursor was synthesized by Na3PO4 and CeCl3.