Synthesis, Surface Modification and Characterization of Magnetic Fe₃O₄@SiO₂ Core-Shell Nanoparticles

Abstract

The nanoparticles of the magnetic core-shell Fe3O4@SiO2 were produced using a modified Stöber approach and functionalized with (3-amino-propyl) APTES triethoxysilane and ethylene-diamine-tetra-acetic acid (EDTA). Magnetic nano adsorbents exhibit many attractive opportunities for different purposes due to their easy removal and possibility of reusing these nanoparticles. The ligands grafting was chemically stable and did not affect the morphology or substrate structure appreciably. APTES-EDTA microspheres were formed for the removal from aqueous solution solutions of trivalent rare earth elements ions since the REEs have a strong oxygen affinity. The advantages of the SiO2 shell that covers the magnetite nanoparticles include lower specific weight and a larger grafting density compared to other surfaces, improving the resistance to acidic environments. Different techniques have described the particle size, morphology, precise surface area and surface alteration including Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), X-ray powder diffraction (XRD), and vibrating sample magnetometer (VSM). The results show that the Fe3O4 nanoparticles with an average particle size of 15 ± 3 nm were successfully synthesized at pH=11, at 25 °C temperature. Moreover, The nanoparticles prepared for Fe3O4 were coated with amorphous SiO2 and functionalized with amino and carboxylic groups.

Advanced superparamagnetic cross‐linked chitosan‐based biosorbent hydrogel for efficient removal of indigo carmine dye from water: Adsorption isotherms, kinetics, and thermodynamic studies

“…attributed to the stretching of O H bonds in the hydroxyl group that is attached to Fe (Figure S2). 49 The FT-IR spectra of CP-MNPs nanoparticles show peaks at 1095 and 2920 cm À1 , which are associated with stretching vibrations of Si O and C H groups, respectively (Figure S1 A2 ). 50 The results confirmed that the 3-CPTMS were effectively grafted onto the surface of Fe 3 O 4 nanoparticles.…”

Studying the impact of cell age on the yeast growth behaviour ofSaccharomyces pastorianusvar.carlsbergensisby magnetic separation

“…[41,42] The bare iron oxide nanoparticles were then coated with silica to increase their colloidal stability, and amine groups were introduced for later functionalisation with ethylenediaminetetraacetic acid (EDTA), as performed in ref. [43] It should be pointed out that the protocol used was modified to obtain the nanoparticle characteristics (Supplementary information [SI]). To do this, 179 mg of bare iron oxide nanoparticles were resuspended in 100 mL of Millipore water and dispersed by ultrasonication on ice (3 min, 20%, 10 s on, 15 s off, 20 kHz, Branson Ultrasonics).…”

“…IONs are very suitable for such processes, as they are inexpensive and easy to functionalise, and they exhibit superparamagnetic behaviour. [43,57,58] The EDTAfunctionalised IONs, stabilised by a silica-shell, have a primary diameter of 142 ± 28 nm and show a maximum binding capacity of 0.0877 ± 0.0062 g Linker-protein /g Nanoparticle to the His-tag of the linker protein (Figure S6A,C,F). Additional characterisation data of the EDTAfunctionalised iron oxide nanoparticles, such as TEM, FT-IR, DLS, and SQUID, is given in the SI.…”

Production of Ni0.5Co0.5Fe2O4/activated carbon@chitosan magnetic nanobiocomposite as a novel adsorbent of methylene blue in aqueous solutions

“…In general, due to the adsorption's low cost and high efficiency, it is the most proper and effective water treatment method. Various compounds have been used as an adsorbent, e.g., carbon nanotubes 10 , activated carbon 11 , zeolite 12 , metal oxides 13 , chitosan 14 , core–shell nanomaterials 15 , magnetic nanocomposites 16 , silicone 17 , and bilayer hydroxides 18 . Among magnetic composites, cobalt ferrite/montmorillonite 19 and graphene oxide/chitosan 20 were evaluated for the removal of methylene blue.…”