Structural dependence of the efficiency of functionalization of silica-coated FeOx magnetic nanoparticles studied by ATR-IR

▶ Propylamino functionalization of magnetic silica-coated FeOx nanoparticles prepared by different methods, including coprecipitation and flame aerosol synthesis, shows different efficiency. ▶ ATR-IR spectroscopy combined with a specific surface reaction allows to determine specifically the chemically available aminopropyl groups on the surface. ▶ Elemental analysis gives an upper bound for the concentration of aminopropyl groups, while ATR-IR additionally provides information about the chemical availability of these groups. ▶ Depending on the structure and surface properties of the silica-coated FeOx nanoparticles results from elemental analysis and ATR-IR measurements can deviate significantly.