Magnetic and Fluorescent Properties of Fe3O4/SiO2/ZnSe Nanocomposites Based on Stabilized Non-Toxic ZnSe Quantum Dots

Abstract

Non-toxic magnetic-fluorescent Fe₃O₄/SiO₂/ZnSe multifunctional nanoparticles were synthesized by a facile chemical route. The nontoxic fluorescent ZnSe quantum dots with -COOH on the surface were assembled around the silica-coated superparamagnetic Fe₃O₄, which were modified with -NH₂ via the chemical bond formed by 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride and N-hydroxysuccinimide between -COOH and -NH₂. The obtained Fe₃O₄/SiO₂/ ZnSe nanocomposites exhibited superparamagnetic behaviour and the saturation magnetization value was 10.76 emu/g from the magnetic spectroscopy. Fluorescent spectroscopy measurements showed that the obtained relative intensity of Fe₃O₄/SiO₂/ZnSe nanocomposites at 400 nm became lower than that of the ZnSe quantum dots.