Preparation of magnetic fluorochromate hybrid nanomaterials with triphenylphosphine surface modified iron oxide nanoparticles and their characterization

• Fe3O4 magnetic nanoparticles were synthesized with hydrothermal method.
• Fe3O4@SiO2 were prepared through a modified Stober method.
• Fe3O4@SiO2 was functionalized with triphenylphosphonium reagent.
• Target hybrid nanomaterial was synthesized by immobilization of fluorochromate anion.

In this study, a new magnetic hybrid nanomaterial Fe3O4@SiO2@PPh3@[CrO3F]− is instituted. Firstly, magnetic Fe3O4 nanoparticles have been synthesized by hydrothermal method. Next, the produced magnetic nanoparticles were covered with a silica shell via modified Stöber method. Then, the core–shell magnetic nanoparticles system Fe3O4@SiO2 functionalization was combined by utilizing (3-chloropropyl)trimethoxysilane and triphenylphosphine, to give the cationic part for immobilization of the anionic part of the Cr(VI) catalysts including [CrO3F]−. The structure of the catalyst after immobilization was investigated by using elemental analysis, X-ray fluorescence (XRF), X-ray diffraction (XRD), Fourier transform infrared (FT-IR), and solid state UV–vis. The particle size and morphology were identified by scanning electron microscope (SEM) and XRD. Magnetization properties of nanoparticles were confirmed by vibrating sample magnetometer (VSM).