钼酸铁的3D结构：相选择性合成、生长机制及磁性

3D architectures of iron molybdate: phase selective synthesis, growth mechanism, and magnetic properties.

作者信息

Ding Yi, Yu Shu-Hong, Liu Chen, Zang Zheng-An

机构信息

Division of Nanomaterials and Chemistry, Hefei National Laboratory for Physical Sciences at Microscale, School of Chemistry and Materials, University of Science and Technology of China, Hefei 230026, P. R. China.

出版信息

Chemistry. 2007;13(3):746-53. doi: 10.1002/chem.200601426.

DOI:10.1002/chem.200601426

PMID:17154198

Abstract

Monoclinic and orthorhombic Fe(2)(MoO(4))(3) microsized particles with complex 3D architectures have been selectively prepared by a template-free hydrothermal process. The pH value, reaction time, temperature, and molybdenian source have crucial influence on the phase formation, shape evolution, and microstructures. Monoclinic Fe(2)(MoO(4))(3) particles obtained at pH 1 and pH 1.65 display ferromagnetic ordering at 10.4 K and 10.5 K, respectively, and the ferromagnetic component is determined to be 0.0458 mu(B) and 0.0349 mu(B) per Fe-ion at 10 K, respectively. For orthorhombic beta-Fe(2)(MoO(4))(3), antiferromagnetic ordering was observed about 12 K. At higher temperatures, beta-Fe(2)(MoO(4))(3) began to follow the Curie-Weiss law with theta=-70 K. Such 3D architectures of monoclinic and orthorhombic beta-Fe(2)(MoO(4))(3) microparticles with unique shapes and structural characteristics may find applications as catalysts and as well as in other fields.

摘要

通过无模板水热法选择性地制备了具有复杂三维结构的单斜晶系和正交晶系的Fe₂(MoO₄)₃微米级颗粒。pH值、反应时间、温度和钼源对相形成、形状演变和微观结构有至关重要的影响。在pH值为1和1.65时获得的单斜晶系Fe₂(MoO₄)₃颗粒分别在10.4 K和10.5 K时显示出铁磁有序，并且在10 K时，每个铁离子的铁磁分量分别确定为0.0458 μB和0.0349 μB。对于正交晶系的β-Fe₂(MoO₄)₃，在约12 K时观察到反铁磁有序。在较高温度下，β-Fe₂(MoO₄)₃开始遵循居里-外斯定律，θ = -70 K。这种具有独特形状和结构特征的单斜晶系和正交晶系β-Fe₂(MoO₄)₃微粒的三维结构可能会在催化剂以及其他领域得到应用。