Preparation And Characterization Of NiFe₂O₄ And Polymer/NiFe₂O₄ Magnetic Nanocomposite Materials

In this article, NiFe₂O₄ and organic polymer/NiFe₂O₄ magnetic nanocomposite were systematically studied. NiFe₂O₄ magnetic nanomaterial was successfully prepared by solvothermal method, biological template method, template-assisted solvothermal method; Polythiophene/NiFe₂O₄?PTh/NiFe₂O₄?, Polyaniline/NiFe₂O₄?PANI/NiFe₂O₄?, Polyfurfural/NiFe₂O₄?FD/NiFe₂O₄?, Polyethylene glycol/NiFe₂O₄?PG/NiFe₂O₄? magnetic nanocomposites were synthesized by a novel one-step solvothermal method. Preparation method, structure, morphology characterization and magnetic of the as-prepared samples were investigated in detail.Nowadays, NiFe₂O₄ was prepared basically by some traditional methods, such as co-precipitation, sol-gel and solvothermal method. In general, the synthesis of polyer/ferrite nanocomposite needs two steps, firstly synthesizing inorganic ferrite and then in-situ polymerizing between polymer monomer and as-prepared inorganic ferrite. The process also needed some precipitation agent, initiator and surface modification agent. Therefore, the complex preparation process, high cost, and unfriendly-environment limited its large-scale application. According to the above problems, NiFe₂O₄ magnetic nanomaterials with different morphology were prepared by three methods using Fe?NO₃?₃·9H₂O and Ni?NO₃?₂·6H₂O as Fe and Ni sources without adding precipitation agent and initiator. At the same time, organic polymer/NiFe₂O₄ magnetic nanocomposite was prepared by one-step solvothermal method using nitrates used to prepared inorganic materials and corresponding polymer monomer as raw materials without adding precipitation agent, initiator and surface modification agent. The prominent advantages of this preparation processes of NiFe₂O₄ and organic polymer/NiFe₂O₄ magnetic nanocomposite are of simpleness,low cost, free pollution from the source and friendly-environment. And the prepared materials have excellent performance.This paper is consists of two aspects:1. NiFe₂O₄ was prepared by three methods: solvothermal method ? template method and template-assisted solvothermal method from Fe?NO₃?₃·9H₂O and Ni?NO₃?₂·6H₂O used as Fe and Ni sources without adding any other alkaline reagent.The effect of solvent, solvothermal temperature, solvothermal time and template on the preparation, material structure, morphology and magnetic property was investigated. The sample was characterized by XRD, TEM, SEM, VSM techniques.The results showed that NiFe₂O₄ would be prepared by the above three methods.NiFe₂O₄ magnetic nanomaterial was prepared by template method and template-assisted solvothermal method, its hollow structure mimic the shape of the cotton fiber. The structure, morphology and magnetic property changed with method changing.2. A series of composite nanomaterials: PTh/NiFe₂O₄, PANI/NiFe₂O₄,FD/NiFe₂O₄ and PG/NiFe₂O₄ had been one-step synthesized by a novel solvothermal method without adding any other alkaline reagent, initiator, surface modification agent and characterized by XDR, IR, TEM, TG, VSM techniques.The results indicted that we have successfully synthesized the above composite materials with superparamagnetism via a modified one-step solvothermal method.Polymers and NiFe₂O₄ were.combined with chemical bonds in the composite materials. The polymers could effectively prevented the aggregation of nanoparticles and controlled the materials crystallite size with different amount.Meanwhile, different high-polymer composites with NiFe₂O₄ have different effect on magnetic materials composition, crystallinity and magnetic properties.