A facile one-pot method to synthesize ultrasmall core-shell superparamagnetic and upconversion nanoparticles

Ultrasmall core-shell Fe3O4@NaYF4:Yb3+/Er3+ nanoparticles with bifunctional properties have been successfully synthesized via one pot thermolysis method using oleylamine as both solvent and stabilizer. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), upconversion (UC) luminescence spectra and the physical properties measurement system (PPMS) were used to characterize the resulting samples. The synthesized samples have uniform morphology with a mean size of 14.5 nm and excellent dispersibility. Moreover, these nanoparticles exhibit superparamagnetic behaviour with saturation magnetization of 8.45 emμ/g and efficient up-conversion emission with a two-photon induced process when excited by a 980 nm laser. These results suggest that the synthesized ultrasmall bifunctional nanoparticles may find many biomedical applications, such as clinical diagnosis and treatment of cancers.

Graphical abstractUltrasmall core-shell Fe3O4@NaYF4:Yb3+/Er3+ nanostructure particles with bifunctional properties have been successfully synthesized via one pot thermolysis method using oleylamine as both solvent and stabilizer.Figure optionsDownload full-size imageDownload high-quality image (80 K)Download as PowerPoint slide