One-Step Synthesis of Size-Tunable Well-Dispersed Iron Oxide Nanoparticles Without Hot Injection
Yu-Chuan Chang1*, Chin-Lin Pan1, En-Szu Lin2, Xin-Da Guo2, Jen-Kai Cheng2, Syun-Long Ye1, Yih-Jaan Tsai1, Cheng-Jhih Jhang1, Tan-Xuan Wu1, Yaw-Teng Tseng1, Hua-Shu Hsu1, Chun-Rong Lin1
1Department of Applied Physics, National Pingtung University, Pingtung 90003, Taiwan
2Department of Applied Chemistry, National Pingtung University, Pingtung 90003, Taiwan
* presenting author:YU-CHUAN CHANG,
Magnetic iron oxide nanoparticles have attracted an increasing interest in the fields of nanoscience and nanotechnology because of the unique and novel physiochemical properties that may find application in diverse areas, including biomedical imaging, drug delivery, sensing, memory devices, etc. The size-tunable iron oxide nanoparticles (1.3-10.6 nm in diameter) were synthesized via thermal decomposition of iron nitrate with hexadecylamine under atmospheric pressure. The mean crystallite size of the particles could be tuned by simply changing the reaction temperature and reaction time. The samples were characterized with X-ray powder diffraction (XRD), Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), magnetic circular dichroism (MCD), transmission electron microscope (TEM) techniques. The reaction mechanism was proposed, and the relationships between the size and the magnetic properties have been investigated. The temperature- and field-dependent magnetization measurements show that all samples exhibit a superparamagnetic behavior at room temperature. The features in MCD spectrum are assigned to the one-ion d-d transitions in Fe3+ and Fe2+ ions, as well to the intersublattice and intervalence charge transfer transitions. The MCD spectrum rearrangement was revealed with the change of the nanoparticles size.

Keywords: Nanoparticle, Magnetic