Volume 11 Issue 2 ( June )

The coprecipitation technique has successfully created iron oxide (Fe3O4) nanoparticles. The surface of Fe3O4 nanoparticles was then modified with luminescent material, namely carbon dots (CDs). CD was synthesized from dried banana leaves using a simple heating method. Then, the Fe3O4@CDs nanocomposite was synthesized using the hydrothermal method of one-pot and two-pot synthesis. The CD is transparent under visible light and looks blue and green under UV illumination. The photoluminescence properties of CDs and Fe3O4@CDs nanocomposite were characterized using photoluminescence (PL) spectrophotometers. Fe3O4@CD synthesized using a one-pot technique has an emission band that broadens towards longer wavelengths, or "redshift." In contrast, Fe3O4@CDs synthesized using a two-pot technique has a higher luminescent intensity than pure CDs. A transmission electron microscopy (TEM) image shows the core-shell structure of the Fe3O4@CDs nanocomposite. Vibrating sample magnetometry (VSM) results show that the nanocomposite has a saturation magnetization of 22.3 emu/g and a coercivity field of 85.41 Oe. The functional groups in Fe3O4@CDs nanocomposite are Fe-O bonds, indicating the formation of Fe3O4, whereas O-H and C=O bonds indicate the formation of CDs. Based on the optical and magnetic characterization, it can be concluded that this material can be developed for a biomedical application, such as a bioimaging material.

Keywords: Nanocomposites, magnetic materials, biocompatibility, carbon dot