Nickel Nanoparticles Immobilized on Magnetic pH-Sensitive Microgel for Catalytic Reduction of Nitriles in Water

Fe3O4 magnetic nanoparticles (MNPs) were modified with (3-aminopropyl) triethoxysilane via the silanization. An ATRP initiating site immobilized onto amine functionalized Fe3O4 MNPs. Surface initiated atom transfer radical polymerization (ATRP) of 4 vinyl pyridine (4VP) was then carried out in the presence of Fe3O4-SiO2-Br nanoparticles, leading to the formation of Fe3O4-SiO2-P4VP hybrid microgels crosslinked with Fe3O4 MNPs. The approach uses polymer microgel as templates for the synthesis of nickel nanoparticles (NiNPs). The tunable properties of synthesized NiNPs@Fe3O4-SiO2- P4VP pH-sensitive microgel were employed in catalytic reduction of aliphatic and aromatic nitriles. Moreover, the catalytic activity of metal nanocomposite has been found that can be modulated by the volume transition of microgel structures with changing pH. Transmission electron microscopy (TEM), x-ray photoelectron spectroscopy (XPS), and x-ray diffraction (XRD), were used to characterize the resultant catalyst