Cerium oxalate hydrate particles were synthesized by precipitation technique under external magnetic field with respective intensities of 0, 0.1, 0.3, and 0.6 T. The particle morphologies were investigated by scanning electron microscopy (SEM) and transmission electron microscope (TEM). Results show that external magnetic field has a great influence on the growth behavior of cerium oxalate hydrate particles. Rod-like and plate-like cerium oxalate hydrate particles with smaller size are formed without the applying of external magnetic field. However, the extremely big rod-like particles with the average size of 12.47 μm were prepared under external magnetic field of 0.6 T. The increasing magnetic field intensity makes the grain grow quickly. Thermogravimetric analysis supports the presence of 8.5 H2O molecules associated with cerium oxalate. Further, the growth mechanism of cerium oxalate hydrate under external magnetic field was briefly discussed.

中文翻译：

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外磁场沉淀法合成草酸铈水合物

在分别为 0、0.1、0.3 和 0.6 T 的外部磁场下通过沉淀技术合成草酸铈水合物颗粒。通过扫描电子显微镜 (SEM) 和透射电子显微镜 (TEM) 研究颗粒形貌。结果表明，外磁场对草酸铈水合物颗粒的生长行为有很大影响。在不施加外磁场的情况下，可以形成更小的棒状和板状草酸铈水合物颗粒。然而，在0.6 T的外磁场下制备了平均尺寸为12.47 μm的极大棒状颗粒。磁场强度的增加使晶粒快速长大。热重分析支持与草酸铈相关的 8.5 个 H2O 分子的存在。