Preparation and Characteristics of Core–Shell Structure Eu(DBM)3Phen@SiO2 Micro-Sphere

Sphere-shape Eu(DBM)3Phen@SiO2 nanoparticles were fabricated by employing a modified alkaline catalyzed hydrolysis and precipitation method. The silica coated on the particles surface was obtained by means of hydrolysis and condensation of tetraethyl orthosilicate (TEOS). In this study, the particles morphology was analyzed by scanning electron microscopy (SEM) and the surface composition of samples was characterized by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR). It is confirmed that the SiO2 shell has been coated on the rare earth complexes successfully. Moreover, the near-infrared photoluminescence emission analysis on the nanoparticles showed that the SiO2 shell would increase the luminescence intensity of Eu(DBM)3Phen. This is primarily due to the reason that SiO2 shell with chemical inertness can effectively reduce the ion Eu3+ non-radiation transition probabilities, as well as the probability of rare earth luminescence quenching caused by the external medium.