Surface-protective assistance of ultrasound in synthesis of superparamagnetic magnetite nanoparticles and in preparation of mono-core magnetite-silica nanocomposites

• Main Authors: Bui, Q. T., Ngo, T. M. H., Tran, T. H.
• Format: Article
• Language: English
• Published: H. : ĐHQGHN 2018
• Subjects: Fe3O4 nanoparticles; Fe3O4@SiO2 nanocomposites; Shock-wave; Ultrasonic assistance; Co-precipitation; Stober method; Crystalline structure-magnetic behaviour relationships
• Online Access: http://repository.vnu.edu.vn/handle/VNU_123/62955; https://doi.org/10.1016/j.jsamd.2018.07.002
• Institution: Vietnam National University, Hanoi

Ultrasound was throughout employed to enhance the co-precipitation process for the synthesis of magnetite nanoparticles (Fe3O4) and the St€ ober approach for the preparation of magnetite-silica nanocomposites (Fe3O4/SiO2). The synthesised magnetite nanoparticles exhibited single-domain nano-crystallites with a uniform spherical morphology, a narrow size distribution (ca. 10 nm), and negligible coercive field (~5 Oe). The prepared magnetite-silica nanocomposites possessed a mono core-shell structure with spherical morphology, biologically coherent size (ca. 100 nm), and discrete mono-domain behaviour. The crystalline structure-magnetic behaviour relationships of the nanomaterials were investigated to imply the presence of a surface protection at nanoscale. The speculation indicated that shock waves took place as the surface-protective role rather than the original mechanical interaction of ultrasound with a larger scope of impact.