Synthesis and characterization of the Fe3O4@SiO2–[Eu(DBM)3phen]Cl3 luminomagnetic microspheres

In this paper, we report fabrication and characterization of the luminomagnetic microspheres (denoted as Fe3O4@SiO2–[Eu(DBM)3phen]Cl3). The fluorescent magnetic microspheres were synthesized via preparing Eu(DBM)3phen]Cl3@SiO2–NH2 nanoparticles first by combination of the solvent precipitation method and the Stöber method, followed by grafting the fluorescent nanoparticles onto Fe3O4. The morphological, textural, magnetic and photoluminescence properties were well-characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), superconducting quantum interference device (SQUID), and photoluminescence spectra. The experimental results show that the core–shell structured luminomagnetic microspheres with an average size of ca. 570 nm possessed high magnetization saturation value (61.7 emu/g) with a negligible coercivity and strong red emission peak (614 nm) from 5D0–7F2 transition of Eu3+ ions, indicating that they have potential applications for optical imaging and time-resolved fluorescence spectroscopy.

Graphical abstractLuminomagnetic Fe3O4@SiO2–[Eu(DBM)3phen]Cl3 microspheres with high magnetic response and fluorescence property have been synthesized via preparing Eu(DBM)3phen]Cl3@SiO2–NH2 nanoparticles first by combination of the solvent precipitation method and the Stöber method and followed by grafting the fluorescent nanoparticles onto the Fe3O4.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Preparation of the [Eu(DBM)3phen]Cl3@SiO2-NH2 fluorescent nanoparticles. ► Coating of the fluorescent nanoparticles onto Fe3O4. ► Improvement of the thermal stability and fluorescent signal of the Eu complex.► The composite with strong magnetic response and fluorescence properties.