Synthesis and characterisation of magnetic-fluorescent Fe sub( 3)O sub( 4)iO sub( 2)nS nanocomposites

Bifunctional magnetic-fluorescent Fe sub( 3)O sub( 4)iO sub( 2)nS nanocomposites were synthesised by a chemical deposition method. The Fe sub( 3)O sub( 4) magnetic nanoparticles as the core were obtained by means of a solvothermal reaction with SiO sub( 2) as the shell. ZnS particles were linked to Fe sub( 3)O sub( 4)iO sub( 2) core-shell nanostructures. The morphology and properties of the resultant Fe sub( 3)O sub( 4)iO sub( 2)nS nanocomposites were investigated by X-ray diffraction, field emission scanning electron microscopy, high-resolution transmission electron microscopy, a vibration sample magnetometer and fluorescence microscopy. The results showed that bead-like structures were built from numerous Fe sub( 3)O sub( 4)iO sub( 2)nS microspheres with an average size of 250 nm. The saturation magnetisation (M sub( s)) value of Fe sub( 3)O sub( 4)iO sub( 2)nS nanocomposites was 22.41 emu/g at room temperature. Furthermore, a strong blue light emission was observed from the nanocomposites under UV light irradiation. The combination of magnetic and fluorescent properties may lead to Fe sub( 3)O sub( 4)iO sub( 2)nS nanocomposites having a variety of potential applications in the field of biomedicine, such as bioimaging and cell separation.