Gruzdev M S, Chervonova U V, Vorobeva V E, Ksenofontov A A, Kolker A M
G. A. Krestov Institute of Solution Chemistry of the Russian Academy of Sciences Ivanovo 153045 Russian Federation
Zavoisky Physical-Technical Institute, FRC Kazan Scientific Center of Russian Academy of Science Kazan 420029 Russian Federation.
RSC Adv. 2019 Jul 22;9(39):22499-22512. doi: 10.1039/c9ra03732b. eCollection 2019 Jul 17.
Poly(propylene imine) dendromesogens (generations from 1 to 4) have been utilized for the synthesis and stabilization of ferrimagnetic FeO nanoparticles. Reduction of Fe(iii) with further oxidation of Fe(ii) results in the formation of highly soluble nanocomposites of iron oxides in a dendrimer, which are stable under a wide range of temperatures. The magnetic iron oxide nanoparticles were investigated by MALDI-ToF MS spectrometry and elemental analysis. To establish the type of mesophase, X-ray measurements were performed at different temperatures. The calculations of X-ray results demonstrate a hexagonal columnar packing of the molecules in the mesophase. Observation of the samples by TEM gives information about the size of the compounds as well as direct evidence of the implementation of FeO nanoparticles into dendrimers. Physical parameters of the magnetic nanoparticles (magnetic moment, effective magnetic anisotropy) have been determined from analyses of the EPR data.
聚（丙烯亚胺）树枝状介晶（1至4代）已被用于合成和稳定亚铁磁性FeO纳米颗粒。Fe(iii)的还原以及Fe(ii)的进一步氧化导致在树枝状大分子中形成高度可溶的铁氧化物纳米复合材料，这些复合材料在很宽的温度范围内都很稳定。通过基质辅助激光解吸电离飞行时间质谱（MALDI-ToF MS）和元素分析对磁性氧化铁纳米颗粒进行了研究。为了确定中间相的类型，在不同温度下进行了X射线测量。X射线结果的计算表明中间相中分子呈六方柱状堆积。通过透射电子显微镜（TEM）对样品进行观察，可获得有关化合物尺寸的信息以及FeO纳米颗粒嵌入树枝状大分子的直接证据。磁性纳米颗粒的物理参数（磁矩、有效磁各向异性）已通过电子顺磁共振（EPR）数据分析确定。
