Biosynthesis of Magnetite Nanoparticles by Green Chemistry Method with Lemon Waste Extract

L. Verástegui, R. Estrada, F. Vázquez, N. Elizondo
Universidad Autónoma De Nuevo León,
United States

Keywords: biosynthesis, magnetite nanoparticles, green chemistry method and lemon waste extract

Summary:

Magnetite (Fe3O4) nanoparticles are very interesting due to its magnetic properties, catalytic, anticorrosive coatings, drug delivery, bimolecular separation, magnetic resonance imaging, cancer diagnosis and treatment, between others. By this, an effective and simple method for synthesis of magnetite (Fe3O4) nanoparticles from ferric chloride (FeCl3) and ferrous sulfate (FeSO4) in the presence of lemon waste extract from ambient temperature to 100 degrees Celsius and atmospheric pressure. Various methods for biosynthesis of magnetite nanoparticles were developed such as micro-emulsion method, thermal decomposition of organic iron precursors in organic solvents, sol-gel method, solvothermal method, hydrothermal synthesis, electrochemical synthesis, ultrasonic chemical co-precipitation. These methods have many disadvantages due to separation and purification of nanoparticles from the oil, surfactant, organic solvents, co-surfactant. We carried out the synthesis of magnetite nanoparticles by co-precipitation of Fe3+ and Fe2+ ions without using toxic organic solvents and surfactants. The effect of extract amount in the reaction mechanism and particle size was studied. The synthesized magnetite nanoparticles were characterized by UV spectrophotometer, X-ray diffraction (XRD), scanning electron (SEM) and transmission electron microscopy (TEM). TEM showed that the synthesized magnetite nanoparticles are highly crystalline and well-monodisperse with a very narrow distribution of 5 nm of average diameter. The biosynthesized magnetite nanoparticles can be easily dispersed in aqueous media. This method provides an effective route to prepare magnetite nanoparticles at low temperature. Lemon waste extract acts as reducing, dispersing and stabilizing agent, which prevents the agglomeration of magnetite nanoparticles (Fe3O4) formed during synthesis. XRD, TEM and SEM data showed that the size and shape of the Fe3O4 nanoparticles depend by the amount of lemon waste extract and the concentration of Fe3+ and Fe2+. Magnetite (Fe3O4) nanoparticles synthesized by this green method were examined by the morphology (size and shape) of Magnetite NPs are used to determined using TEM or high-resolution transmission electron microscopy (HRTEM) for both the equipment we found their energy dispersive X-ray spectroscopy (EDX) analysis. The samples were prepared by drop casting of magnetite Nps solution onto a lacey carbon TEM grid. X-ray diffractometer, XRD-MiniFlex (Rigaku, Japan) equipped with Cu Kα radiation source. All XRD data were collected under the experimental conditions in the angular range 3o ≤ 2θ ≤ 60o. UV Spectra magnetite nanoparticles were obtained in the range of wavelength from 300 to 800 nm in an UV spectrometer Thermo scientific. This green method in the present study offers several important advantageous features. First, Fe3O4 nanoparticles are synthetized easily by different amounts of lemon waste extract. Second, the biosynthesis method is environmentally friendly and economical, because it involves inexpensive and non-toxic materials. Therefore this green chemistry method is economic, ecological and easily for the nanofabrication.