Pure Iron Oxide Nanoparticles Research Articles

Analysis and characterization of opto-electronic properties of iron oxide (Fe2O3) with transition metals (Co, Ni) for the use in the photodetector application

There are several uses for ultraviolet photodetectors, including in the scientific, military, and industrial sectors. In this sense, UV photodetectors must have high responsiveness, be insensitive to visible light, and be inexpensive to produce. For this purpose, we report the development of Co and Ni based iron oxide nanoparticles via the cost effective low temperature sol–gel auto-combustion process. XRD study approves the cubic crystal structure of iron oxide (Fe2O3) with predominant orientation along (311) direction. A sharp and strong peak is obtained at 583 cm−1 and 594 cm−1 for both samples in FT-IR spectra assigned to metal oxide Fe–O network system which approves the formation of iron oxide. Raman spectroscopy analysis reveals the presence of two A1g and five Eg phonon modes in the case of both samples. Absorption study exhibits the strong absorption peaks for the iron oxide sample doped with cobalt and nickel, while poor absorption was noticed from the pure iron oxide nanoparticles. The large and low energy band gap values are found to be 2.77 eV and 1.68 eV for pure Fe2O3 and cobalt and nickel doped Fe2O3 nanoparticles, respectively. Stone and cloud-like shape morphology was observed from SEM analysis. The EDX spectra reveal the presence of essential elements, like Fe and O in the case of pure iron oxide while Fe, O, Co and Ni in the case of transition metals doped iron oxide nanoparticles. The photoluminescence (PL) spectroscopy technique was recorded the luminescent properties which reveals the decrease in PL intensity that confirms the decline in electron–hole recombination. Therefore, I–V characterization analysis reveals that electrical conductivity increases with the addition of metals due to decrease in electron–hole recombination with the co-doping of metals. These modified opto-electronic properties of the developed Fe2O3 by metals co-doping make it suitable candidate for the use in photodetector application.

Rare-Earth Doped Iron Oxide Nanostructures for Cancer Theranostics: Magnetic Hyperthermia and Magnetic Resonance Imaging.

Superparamagnetic iron oxide nanoparticles (SPIONs) have been extensively investigated during the last couple of decades because of their potential applications across various disciplines ranging from spintronics to nanotheranostics. However, pure iron oxide nanoparticles cannot meet the requirement for practical applications. Doping is considered as one of the most prominent and simplest techniques to achieve optimized multifunctional properties in nanomaterials. Doped iron oxides, particularly, rare-earth (RE) doped nanostructures have shown much-improved performance for a wide range of biomedical applications, including magnetic hyperthermia and magnetic resonance imaging (MRI), compared to pure iron oxide. Extensive investigations have revealed that bigger-sized RE ions possessing high magnetic moment and strong spin-orbit coupling can serve as promising dopants to significantly regulate the properties of iron oxides for advanced biomedical applications. This review provides a detailed investigation on the role of RE ions as primary dopants for engineering the structural and magnetic properties of Fe3 O4 nanoparticles to carefully introspect and correlate their impact on cancer theranostics with a special focus on magnetic hyperthermia and MRI. In addition, prospects for achieving high-performance magnetic hyperthermia and MRI are thoroughly discussed. Finally, suggestions on future work in these two areas are also proposed.

Microstructural evaluation of iron oxide nanoparticles at different calcination temperature by Scherrer, Williamson-Hall, Size-Strain Plot and Halder-Wagner methods

ABSTRACT Ferric nitrate Fe(NO3)3 ⋅9H2O as a precursor and Ethylene Glycol as a solvent were used to prepare iron oxide nanoparticle via sol gel method. X-ray diffraction (XRD) study of IONPs at different calcination temperatures to determine the size of the crystallite was performed using various methods of calculation: Scherrer, Williamson-Hall (W-H), Halder-Wagner (H-W) and Size-Strain plot (SSP). The Scherrer and H-W methods reveal that the crystallite size decreases in the presence of a single phase (γ-Fe2O3) at lower temperature, as the contribution of other-phase (α-Fe2O3) increases size varies, but again decreases as the material converts to a single phase, while with temperature, the Size-Strain Plot and Halder-Wagner Method show increased crystallite size. FE-SEM and HR-TEM investigations confirm that the synthesized IONPs are spherical. EDX spectra and FTIR analyses have shown that synthesized particles are pure iron oxide nanoparticles. The average particle size calculated using different models below than 20 nm.

Synthesis and Characterization of a Novel Bio-Magnetically Recoverable Palladium Nanocomposite for the Photocatalytic applications

A novel immobilized sparteine palladium (II) complex on the bio α-Fe2O3 nanoparticles was synthesized (Pd-Sparteine- α -Fe2O3). XPS, FT-IR, and ICP were used to determine compositional information. High thermostability and magnetic properties of it were proved by TGA and VSM, respectively. The size and morphology of this heterogeneous catalyst were investigated using SEM and TEM. Photoluminescence spectrum, BET, DRS and EDAX of this novel nanocomposite were evaluated for further investigations. The synthesized magnetic nanohybrid was successfully exploited as a new recyclable heterogeneous photocatalyst in the degradation of 2,4- dichlorophenol under visible light irradiation. It exhibited better photocatalytic efficiency of Pd-Sparteine-α-Fe2O3 was much higher than that of pure iron oxide nanoparticles. High yield and low reaction time of this catalyst were indicated that Pd-Sparteine-α -Fe2O3 could be a promising catalyst for direct photocatalyst applications.

A novel synthesis and characterization of polyhedral shaped amorphous iron oxide nanoparticles from incense sticks ash waste

This research study has investigated the potential applicability of incense sticks ash (ISA), a waste material, in synthesizing highly pure iron oxide nanoparticles (IONPs). Synthesis of IONPs from ISA involved five major steps: burning of incense sticks to collect ISA, recovery of ferrous fractions from wet slurry by magnetic separation method, acidic treatment of ferrous fractions under sonication, formation of IONPs by co-precipitation method by using NaOH, calcination of the obtained powder in a muffle furnace. The IONPs synthesized from ISA extracted ferrous particles have two different types of particles, small circular disk shaped of size 60–200 nm in diameter, while larger rectangular particles whose diameter was 150–600 nm by length. The formation of large particles is due to the agglomeration of several small IONPs. The synthesized nanoparticles were amorphous and polyhedral in shape. These IONPs were characterized by Particle size analyzer (PSA), X-ray powder diffraction (XRD), Transmission Electron Microscopy (TEM), Field emission-scanning electron microscopy (FESEM), Electron diffraction spectroscopy (EDS), Atomic Force Microscopy (AFM) and Fourier-transform infrared spectroscopy (FTIR). The FTIR spectra revealed the characteristic bands at 452 and 565 cm−1 which is attributed to Fe–O bonds of IONPs, while the XRD diffractogram supported the amorphous nature of IONPs by showing a broad peak at 2θ, 36.090. The average particle size and polydispersity index (PDI) revealed by PSA was 734.9 nm and 0.357respectively. Since the size given by PSA is in hydrodynamic radius so there is large average size of the particles. The polyhedral shape was confirmed by the microscopic techniques while the presence of Fe and O peaks only by EDS confirmed the purity of the synthesized IONPs. The result obtained in the mentioned method proves that ISA waste can be utilized to synthesize highly pure IONPs by an economical and eco-friendly approach. The current method also focuses on the reduction of solid waste and water pollution arising due to the ISA disposal in water bodies. In, future, ISA may be used as substitute source material for all the ferrous and ferrous based industries (steel). Moreover, based on the purity, in subsequent time it could be used in magnetic resonance imaging (MRI), drug delivery, and as an adsorbents for the environmental clean-up.

Surface modification of super paramagnetic iron oxide nanoparticles via milk casein for potential use in biomedical areas

Super paramagnetic iron oxide nanoparticles (SPIONs) have proved that they have tremendous potential to use in various biomedical applications. But the surface of pure iron oxide nanoparticles so fast oxidized, that is a major drawback for biomedical applications. Covered SPIONs have good surface activity. Therefore, the first goal was to synthesize the naked SPIONs. Then we modified with 3-Aminopropyltriethoxysilane (APTES) and trichlorotriazine (TCT). Several techniques measurements were used for characterization the size and special features of naked SPIONs and TCT modified SPIONs. These results show that the SPIONs were synthesized. After that the SPIONs are coated with casein and indicate that there is an interaction between them. Moreover, we have investigated magnetic properties and anticancer effects of casein-coated SPIONs. Therefore, we showed casein could be used to increase the biocompatibility of the surface of SPIONs. At the end, we show that bonding of dipyridamole (DIP) to the surface of casein-coated SPIONs have good magnetite properties for targeted drug delivery. We find that the release of DIP by casein-coated SPIONs-DIP was sensitive to pH. Both release curves in pH 5.5 and 7.4 showed the release of DIP by β-casein coated SPIONs-DIP better than α-casein coated SPIONs-DIP. The cell culture studies of the casein-coated SPIONs-DIP provide good anticancer effects against both breast and prostate cancer cell lines. Here, we propose a simple and inexpensive chemical method for preparation of highly biocompatible core–shell SPIONs and binding of drug for using in targeted drug delivery system. Communicated by Ramaswamy H. Sarma

Multifunctional iron oxide-carbon hybrid nanoparticles for targeted fluorescent/MR dual-modal imaging and detection of breast cancer cells

An efficient method for the highly sensitive and specific detection of cancer cells is crucial for the early diagnosis of cancer. In this work, we propose a one-pot approach to fabricating magnetic-fluorescent iron oxide-carbon hybrid nanomaterials (MCNP) with excellent stable, high quantum yield and excellent magnetic properties for breast cancer cells recognition and detection via magnetic resonance and multicolour fluorescence imaging. MCNPs were efficiently synthesised via one-pot, multi-component reactions of FeCl3, FeCl2•4H2O, citric acid and ethylenediamine in diethylene glycol. The MCNPs showed strong excitation wavelength-dependent fluorescence in the blue-red region with a high quantum yield of 58.4%, and they presented higher stability and T2 relaxivity than pure iron oxide nanoparticles. After conjugating with CD44 monoclonal antibodies, the fabricated targeting nanoprobe, MCNPs-CD44, demonstrated a specific fluorescence/MRI dual imaging contrast effect in 4T1 breast cancer cells. Biological transmission electron microscope imaging showed a significant preferential uptake of the nanoparticle conjugates by the 4T1 cells. By taking advantage of the high binding affinity and specificity of the CD44 antibodies to the overexpressed CD44 on the cancer cell surface, the developed MCNPs-CD44 probe distinguished 4T1 breast cancer cells from normal cells and detected as low as a few hundred cancer cells, thus indicating the potential application of multifunctional nanocomposites in the MR diagnosis and fluorescence positioning of breast cancer at cellular-level resolution.

Assessing the hyperthermic properties of magnetic heterostructures: the case of gold-iron oxide composites.

Gold-iron oxide composites were obtained by in situ reduction of an Au(III) precursor by an organic reductant (either potassium citrate or tiopronin) in a dispersion of preformed iron oxide ultrasmall magnetic (USM) nanoparticles. X-ray diffraction, transmission electron microscopy, chemical analysis and mid-infrared spectroscopy show the successful deposition of gold domains on the preformed magnetic nanoparticles, and the occurrence of either citrate or tiopronin as surface coating. The potential of the USM@Au nanoheterostructures as heat mediators for therapy through magnetic fluid hyperthermia was determined by calorimetric measurements under sample irradiation by an alternating magnetic field with intensity and frequency within the safe values for biomedical use. The USM@Au composites showed to be active heat mediators for magnetic fluid hyperthermia, leading to a rapid increase in temperature under exposure to an alternating magnetic field even under the very mild experimental conditions adopted, and their potential was assessed by determining their specific absorption rate (SAR) and compared with the pure iron oxide nanoparticles. Calorimetric investigation of the synthesized nanostructures enabled us to point out the effect of different experimental conditions on the SAR value, which is to date the parameter used for the assessment of the hyperthermic efficiency.

Microwave-assisted one-step hydrothermal synthesis of pure iron oxide nanoparticles: magnetite, maghemite and hematite

A simple, rapid, one-step synthesis way of pure iron oxide nanoparticles: magnetite (Fe3O4), maghemite (γ-Fe2O3) and hematite (α-Fe2O3) was investigated. Nanoparticles were prepared by microwave synthesis, from ethanol/water solutions of chloride salts of iron (FeCl2 and FeCl3) in the presence of sodium hydroxide NaOH. X-ray powder diffraction (XRD), Transmission Electron Microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS) were used to characterize these nanoparticles.