Synthesis and luminescent properties of monodisperse core–shell structured SiO2@Lu2O3:Eu3 + microspheres

• SiO2@Lu2O3:Eu3 + core–shell microspheres were prepared via a mild solvothermal method.
• SiO2@Lu2O3:Eu3 + core–shell microspheres are monodisperse, uniform and submicron scale.
• The obtained core–shell microspheres exhibit excellent red-luminescent properties.

Highly monodispersed SiO2@Lu2O3:Eu3 + core–shell microspheres were successfully synthesized by coating the Lu2O3:Eu3 + nanoparticles onto the surface of non-aggregated spherical SiO2 particles via a simple solvothermal method, followed by a subsequent calcination process. The as-prepared phosphors were characterized by X-ray diffraction (XRD), Fourier transform infrared spectrum (FT-IR), thermal analysis (TGA-DSC), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectrometry (EDS), selected area electron diffraction (SAED), high resolution transmission electron microscopy (HRTEM), and photoluminescence spectra (PL). The as-obtained core–shell microspheres show strong red emission corresponding to the 5D0 → 7F2 transition of the Eu3 + ions under ultraviolet (UV) excitation, which may have potential applications in light-emitting phosphors, field emission displays, advanced flat panel displays and biological labeling.

This picture is the illustration for the formation process of the SiO2@Lu2O3:Eu3 + composite microspheres. Well-dispersed and uniform silica cores were used as template, and then a continuous europium-doped lutetium oxide precursor shells were homogeneously coated over the silica spheres template. At last, SiO2@Lu2O3:Eu3 + composite microspheres were obtained by calcinating the corresponding precursors at 800 °C for 2 h in air.Figure optionsDownload as PowerPoint slide