Fabrication of bifunctional core-shell Fe3O4 particles coated with ultrathin phosphor layer
1 Department of Physics and Astronomy, Seoul National University, Seoul 151-747, Republic of Korea
2 Department of Nanomaterials Engineering, Pusan National University, Miryang 627-706, Republic of Korea
Nanoscale Research Letters 2013, 8:357 doi:10.1186/1556-276X-8-357Published: 21 August 2013
Bifunctional monodispersed Fe3O4 particles coated with an ultrathin Y2O3:Tb3+ shell layer were fabricated using a facile urea-based homogeneous precipitation method. The obtained composite particles were characterized by powder X-ray diffraction, transmission electron microscopy (TEM), quantum design vibrating sample magnetometry, and photoluminescence (PL) spectroscopy. TEM revealed uniform spherical core-shell-structured composites ranging in size from 306 to 330 nm with a shell thickness of approximately 25 nm. PL spectroscopy confirmed that the synthesized composites displayed a strong eye-visible green light emission. Magnetic measurements indicated that the composite particles obtained also exhibited strong superparamagnetic behavior at room temperature. Therefore, the inner Fe3O4 core and outer Y2O3:Tb3+ shell layer endow the composites with both robust magnetic properties and strong eye-visible luminescent properties. These composite materials have potential use in magnetic targeting and bioseparation, simultaneously coupled with luminescent imaging.