Iron Acetylacetonate Research Articles

Single-step synthesis of carbon nanotubes/iron/iron oxide composite films through inert-ambient CVD using ferric acetylacetonate as a precursor

Fe–Fe3O4–CNT composite thin film was obtained by single step chemical vapor deposition process using Fe(acac)3 as the sole precursor. By changing the deposition pressure, the form of carbon deposited could be changed from amorphous to CNTs.

Large-scale fabrication and application of magnetite coated Ag NW-core water-dispersible hybrid nanomaterials.

In this work, we report a large scale synthetic procedure that allows attachment of magnetite nanoparticles onto Ag NWs in situ, which was conducted in a triethylene glycol (TREG) solution with iron acetylacetonate and Ag NWs as starting materials. The as-prepared Ag NW/Fe3O4 NP composites are well characterized by SEM, TEM, XRD, XPS, FT-IR, and VSM techniques. It was found that the mass ratio of iron acetylacetonate to Ag NWs plays a crucial role in controlling the amount of magnetite nanoparticles decorated on the Ag NWs. The resulting Ag NW/Fe3O4 NP composites exhibit superparamagnetic properties at room temperature, and can be well dispersed in aqueous and organic solutions, which is greatly beneficial for their application and functionality. Thus, the as-prepared magnetic silver nanowires show good catalytic activity, using the catalytic reduction of methylene blue (MB) as a model reaction. Furthermore, the Ag NW/Fe3O4 NP composites can be functionalized with polydopamine (Pdop), resorcinol-formaldehyde resin (PFR), and SiO2, respectively, in aqueous/ethanol solution. Meanwhile they can also be coated with polyphosphazene (PZS) in organic solution, resulting in a unique nanocable with well-defined core shell structures. Besides, taking Ag NW/Fe3O4@SiO2 as an example, a hollow magnetic silica nanotube can be obtained with the use of Ag NWs as physical templates and a solution of ammonium and H2O2. These can greatly improve the application of the Ag NW/Fe3O4 NP composites. The as-synthesized above nanocomposites have high potential for applications in the fields of polymers, wastewater treatment, sensors, and biomaterials.

Composition and hydrophilicity control of Mn-doped ferrite (MnxFe3-xO4) nanoparticles induced by polyol differentiation.

Manganese doped ferrite (MnxFe3-xO4) nanoparticles with x = 0.29-0.77 were prepared under solvothermal conditions in the presence solely of a polyol using the trivalent manganese and iron acetylacetonates as precursors. In this facile approach, a variety of polyols such as polyethylene glycol (PEG 8000), tetraethylene glycol (TEG), propylene glycol (PG) and a mixture of TEG and PG (1 : 1) were utilized in a triple role as a solvent, a reducing agent and a surface-functionalizing agent. The composition of the fine cubic-spinel structures was found to be related to the reductive ability of each polyol, while determination of structural characteristics plus the inversion parameter (i = 0.18-0.38) were provided by X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) spectroscopy at both the Fe and Mn K-edges. The saturation magnetization increased up to 80 emu g(-1) when x = 0.35 and i = 0.22. In addition, the as-prepared nanocrystals coated with PEG, PG and PG&TEG showed excellent colloidal stability in water, while the TEG-coated particles were not water dispersible and converted to hydrophilic when were extra PEGylated. Measurements of the (1)H NMR relaxation in water were carried out and the nanoprobes were evaluated as potential contrast agents.

Synthesis and characterization of biodegradable polyurethane for hypopharyngeal tissue engineering.

Biodegradable crosslinked polyurethane (cPU) was synthesized using polyethylene glycol (PEG), L-lactide (L-LA), and hexamethylene diisocyanate (HDI), with iron acetylacetonate (Fe(acac)3) as the catalyst and PEG as the extender. Chemical components of the obtained polymers were characterized by FTIR spectroscopy, 1H NMR spectra, and Gel Permeation Chromatography (GPC). The thermodynamic properties, mechanical behaviors, surface hydrophilicity, degradability, and cytotoxicity were tested via differential scanning calorimetry (DSC), tensile tests, contact angle measurements, and cell culture. The results show that the synthesized cPU possessed good flexibility with quite low glass transition temperature (T g, −22°C) and good wettability. Water uptake measured as high as 229.7 ± 18.7%. These properties make cPU a good candidate material for engineering soft tissues such as the hypopharynx. In vitro and in vivo tests showed that cPU has the ability to support the growth of human hypopharyngeal fibroblasts and angiogenesis was observed around cPU after it was implanted subcutaneously in SD rats.

Hexagonal magnetite nanoprisms: preparation, characterization and cellular uptake.

The capacity of iron oxide nanocrystals to heat tissue when subjected to an alternating magnetic field (AMF hyperthermia) is shape-selective. Although iron oxide nanostructures with numerous shapes have been synthesized to date, hexagonal Fe3O4 prisms of low toxicity remained elusive. Here, we report the use of a dual ligand system permitting feasible reaction conditions to synthesize nearly perfect hexagonal Fe3O4 nanoplatelet structures, with edge length of 45 ± 5 nm and thickness of 5 to 6 nm. Their Specific Absorption Rate (SAR) is >750 W g(Fe)-1. The Fe3O4 hexagons were coated with a dopamine-based ligand to increase dispersibility in aqueous buffers. The Fe3O4 hexagons were only minimally toxic to RAW264.7 cells, which can be utilized in cell-based cancer targeting approaches.

Synthesis, Characterization, and Nanocatalysis Application of Core–Shell Superparamagnetic Nanoparticles of Fe3O4@Pd

There is a wide number of different synthetic methods to obtain magnetite (Fe3O4) superparamagnetic nanoparticles (SPNPs). However, only a few are able to produce very small and well defined SPNPs with narrow size distribution. We report a modification of the metal-complex decomposition in organic media method in which we replace iron(iii) acetylacetonate (Fe(Acac)3) with an iron–urea complex (Fe-Urea) as metal source for the synthesis. With this modification we were able to obtain small particle sizes with a good control in size distribution. The Fe-Urea complex is easy to prepare with excellent yields. Core–shell nanoparticles are then prepared using palladium(ii) acetylacetonate as a Pd source, to obtain a Pd0 shell stabilised by oleylamine. The core–shell superparamagnetic nanoparticles of Fe3O4@Pd-OA are extensively characterized by FT-IR, powder X-ray diffraction, transmission electron microscopy, UV-vis, thermogravimetric analysis/differential scanning calorimetry, and magnetic susceptibility measurements, and tested in a palladium-catalyzed cross-coupling Suzuki–Miyaura reaction with promising results.

Living radical polymerization of vinyl acetate mediated by iron(iii) acetylacetonate in the presence of a reducing agent

The Fe(acac)3-mediated OMRPs of VAc in the presence of a reducing agent were reported.

Synthesis and Application of Magnetic Iron Oxide Nanoparticles as High Efficiency Magnetic Resonance Imaging Contrast Agent

Iron oxide nanoparticles were synthesized by thermal decomposition of iron (III) acetylacetonate (Fe(acac)3) in poly(ethylene glycol) (PEG), which was used as the solvent, reducing agent and modifying agent. X-ray powder diffraction (XRD) analysis indicates that the nanoparticles have magnetite crystal structure. The results of transmission electron microscope (TEM) show that the shapes of iron oxide nanoparticles coated with PEG are equiaxial with uniform morphology. Particles and Zeta potential analyses show that the surface of iron oxide nanoparticles is negatively charged, and their hydrodynamics size dispersed in deionized water is 20 nm. Iron oxide nanoparticles show superparamagnetic behavior at room temperature and high r2/r1 ratio. MTT studies show that PEG-SPIONs have low cytotoxicity. In vivo magnetic resonance imaging reveals their excellent contrast effects of the PEG-SPIONs. This work demonstrates that iron oxide nanoparticles coated with PEG can be excellent T2 MRI contrast agents.

Effect of iron acetylacetonate on the crosslink structure, thermal and flammability properties of novel aromatic diamine-based benzoxazines containing cyano group

Fe(AcAc)3 speeds up the curing reaction of BAPBACP monomer and improves the thermal and flammability properties of the cured resin.

One-pot synthesis of water-soluble superparamagnetic iron oxide nanoparticles and their MRI contrast effects in the mouse brains.

Water-soluble superparamagnetic iron oxide nanoparticles (SPIONs) were synthesized by the thermal decomposition of iron (III) acetylacetonate (Fe(acac)3) in the mixture of poly(ethylene glycol) (PEG) and poly(ethylene imine) (PEI). The average sizes of the SPIONs are in the range of 6-12nm, which could be tuned by adjusting the synthesis temperature and molecular weight of PEI. Benefiting from the coating of hydrophilic PEG and PEI, the resulted SPIONs showed excellent colloidal stability in deionized water and other physiological buffers. The XRD patterns indicate that the obtained SPIONs are magnetite. The PEG/PEI-SPIONs exhibited high r2/r1 ratio. In vivo magnetic resonance imaging (MRI) of the mouse brains after intravenous injection of the SPIONs showed their good contrast effect. Considering the facile fabrication process and excellent imaging performance of the water soluble PEG-SPIONs and PEG/PEI-SPIONs, it is believed that the SPIONs will find great potential in advanced MRI.

Superparamagnetic iron oxide nanoparticles coated with different polymers and their MRI contrast effects in the mouse brains

PEG and PEG/PEI modified superparamagnetic iron oxide nanoparticles (SPIONs) were synthesized by the thermal decomposition of iron (III) acetylacetonate (Fe(acac)3) in poly (ethylene glycol) (PEG) containing poly (ethylene imine) (PEI) (0 or 0.3g). PEG/PEI-SPIONs were coated with Tween 80 (PEG/PEI/Tween 80-SPIONs). Fourier transform infrared spectroscopy (FTIR) analyses indicated that PEG, PEG/PEI and PEG/PEI/Tween 80 were attached to the surfaces of the SPIONs. The PEG-SPIONs, PEG/PEI-SPIONs and PEG/PEI/Tween 80-SPIONs performed excellent colloidal stability in the phosphate buffered saline (PBS), and in deionized water with the mean hydrodynamic sizes of 19.5, 21.0, 24.0nm and the zeta potentials of -5.0, 35.0, 19.0mV, respectively. All the SPIONs showed low cytotoxicity assessed by the MTT assay. In vivo magnetic resonance imaging (MRI) of the Kunming (KM) mouse brains were performed, the PEG-SPIONs, PEG/PEI-SPIONs and PEG/PEI/Tween 80-SPIONs exhibited vascular imaging effects in bulbus olfactorius, frontal cortex, temporal, thalamus and brain stem of the mouse brains after 24h intravenous injection of the nanoparticles. The SPIONs have potentials as MRI contrast agents in the mouse brains.

Thermal and Tensile Behavior of HD-PE Films Containing Iron (III) Acetylacetonate after UV Irradiation

Abstract The thermal, tensile and other properties of high density polyethylene films containing iron (III) acetylacetonate as pro-oxidant additive have been studied after exposure to UV irradiation for up to 300 h. The effect of photooxidation on polyethylene films with and without pro-oxidant was estimated by Fourier transform infrared spectroscopy, X-ray diffraction analysis, Differential scanning calorimeter measurements and the tensile properties. It was observed that UV irradiation had almost no effect on the melting temperature of the different samples. After exposure, the degree of crystallinity increased from 69% to 72% for the initial polyethylene samples without pro-oxidant additive and by 3% for the samples containing iron (III) acetylacetonate. It was found that the increase in the carbonyl index of initial HDPE was not significant even after 60 h exposure to UV irradiation while samples with pro-oxidant suffered substantial degradation still for 35 h. It was observed that the decrease of the tensile strength is more pronounced for the samples with pro-oxidant under irradiation for 60 to 70 h. The films containing pro-oxidant lose ∼90% of its initial elongation at break after 35 h exposure.

Effects of ferrite catalyst concentration and water vapor on growth of vertically aligned carbon nanotube

In this study Fe3O4 nanoparticles were used as catalysts for the growth of vertically aligned carbon nanotubes (VA-CNTs) by chemical vapor deposition (CVD). The effect of catalyst concentration and water vapor during the CVD process on the properties of the VA-CNTs was investigated. Monodisperse Fe3O4 nanoparticles (4.5–9.0 nm diameter) prepared by thermal decomposition of iron acetylacetonate compounds were spin-coated on clean silicon substrates which served as a platform for VA-CNTs growth. The results indicated that the length, density and growth rate of CNTs were strongly affected by the catalyst concentration. CNTs grown at 0.026 g ml−1 Fe3O4 catalyst had greater length, density and growth rates than those obtained at 0.01 and 0.033 g ml−1 Fe3O4 catalyst. Addition of water during the CVD process had drastically improved CNTs growth. The length and growth rate of obtained CNTs were 40 μm and 1.33 μm min−1, respectively. The results provided insights into the role of Fe3O4 catalyst and water vapor during VA-CNTs growth process by CVD method and the obtained information might serve as a starting point for further optimization of VA-CNTs synthesis.

Mangiferin loaded magnetic PCEC microspheres: preparation, characterization and antitumor activity studies in vitro.

Mangiferin is a promising effective chemopreventive agent against various tumors. However, its clinical use is limited by poor water solubility and low bioavailability. In this article, mangiferin loaded magnetic PCEC microspheres (MG-MS) were designed, characterized and the antitumor activity of MG-MS was evaluated in vitro. The magnetic nanoparticles (MNP) were synthesized via the high-temperature reaction of iron acetylacetonate in phenyl ether in the presence of oleic acid and oleylamine. Poly (ε-caprolactone)-poly (ethyleneglycol)-poly (ε-caprolactone) (PCL-PEG-PCL, PCEC) copolymers were formed by ring-opening copolymerization of ε-CL initiated by PEG-diol using Sn(Oct)2 as a catalyst and MG-MS were prepared by solvent diffusion method. MNP, PCEC copolymer, and MG-MS were characterized by GPC, TEM, XRD, FT-IR, 1H-NMP and Malvern Laser Particle Sizer. Meanwhile, the antiproliferative activity in vitro and in vitro release behavior of this microspheres were studied in detail. The results indicate that the obtained magnetic microspheres might have great potential as an effective carrier for mangiferin used in cancer chemotherapy.

Specific Power Absorption of Silica-coated Magnetite Cubes

We have developed silica stabilized ferrimagnetic magnetite nanocubes (MNCs) as effective heat mediators for magnetic hyperthermia. To do that, large hydrophobic magnetite nanoparticles, with a mean size of 79 and 124 nm were synthesized and transferred to water by silica surface modification. The heating ability of these water suspensions was studied by measuring the Specific Power Absorption (SPA) applying an AC magnetic field of amplitude H0 = 45 kA/m and frequency f = 360 kHz. High SPA values were obtained, ranging from 560 to 1160 W/g. The normalization of the SPA values by the inverse of the frequency and squared field amplitude was performed in order to compare our results with these described in literature. The SPA value for our samples, normalized in this way, yielded values of 0.7-1.5 nH m2/kg. Keywords: Iron (III) acetylacetonate, ferromagnetic, magnetic hyperthermia, magnetite nanocubes, silica modification.

Size control synthesis and high coercivity L10-FePt nanoparticles produced by iron (III) acetylacetonate salt

Monodisperse 4.11nm FePt nanoparticles were synthesized via chemical co-reduction of iron (III) acetylacetonate and platinum (II) acetylacetonate by 1,2-hexadecanediol as a reducing agent. Then through the seed mediated growth process smaller sized FePt nanoparticles are used as seeds for the growth of larger sized particles. There is no specific limitation to achieve upper size range by this method. In this work, we have successfully synthesized FePt nanoparticles up to 8.32nm. After annealing these particles become ferromagnetic and their coercivirty increases with increasing particle sizes and reaches a maximum value of 17760Oe for size of 8.32nm.

On synthesis of Fe2SiO4/SiO2 and Fe2O3/SiO2 composites through sol–gel and solid-state reactions

Major processing factors in forming Fe2SiO4/SiO2 and Fe2O3/SiO2 powders via sol–gel synthesis followed by solid-state reactions are investigated. The results clearly indicate that the chemical compositions of the precursors, the ratio of the precursors, the nature of the catalyst used, and the gas atmosphere during solid-state reactions can all affect the outcome of the reaction product(s). The formation of Fe2SiO4/SiO2 is enhanced by using the precursor iron(III) acetylacetonate as the Fe source with the precursor ratio of iron(III) acetylacetonate to tetraethyl orthosilicate being 1:1 and the addition of formic acid. Otherwise, crystalline Fe and Fe3C are formed in place of Fe2SiO4. By altering the gas atmosphere during solid-state reactions from argon to oxygen, the reaction products change from Fe2SiO4/SiO2 to Fe2O3/SiO2. All of the observed phenomena can be rationalized via the degree of mixing of the Fe–O and Si–O domains at the molecular level in the gel network during sol–gel reactions and the presence of a reducing or oxidizing atmosphere during the solid-state reaction.

Bulk AGET ATRP of methyl methacrylate using iron(iii) acetylacetonate as a catalyst

In this work, polymerization of methyl methacrylate (MMA) was successfully conducted by atom transfer radical polymerization with activators generated by electron transfer (AGET ATRP) at 90 °C, using iron(III) acetylacetonate (Fe(acac)3) as a catalyst, ethyl alpha-bromophenylacetate (EBPA) as an initiator, ascorbic acid (AsAc) as a reducing agent and triphenyl phosphine (PPh3) as a ligand. The polymerization kinetics showed that the polymerization rate (the conversion reached up to 98.1% after 60 min) was much higher than that mediated by inorganic iron salts and it was affected by the feed of the iron catalyst. Moreover, the kinetic plots were linear, and the molecular weights of the resulting polymers with molecular weight distribution around 1.2, increased linearly with monomer conversions, indicating good features of “living”/controlled radical polymerizations. The end-functionality of the polymers was confirmed by 1H NMR spectroscopy and a chain extension experiment.

Ultrathin hematite films deposited layer-by-layer on a TiO2 underlayer for efficient water splitting under visible light

Ultrathin hematite (α-Fe2O3) film deposited on a TiO2 underlayer as a photoanode for photoelectrochemical water splitting was described. The TiO2 underlayer was coated on conductive fluorine-doped tin oxide (FTO) glass by spin coating. The hematite films were formed layer-by-layer by repeating the separated two-phase hydrolysis-solvothermal reaction of iron(III) acetylacetonate and aqueous ammonia. A photocurrent density of 0.683 mA cm−2 at +1.5 V vs. RHE (reversible hydrogen electrode) was obtained under visible light (>420 nm, 100 mW cm−2) illumination. The TiO2 underlayer plays an important role in the formation of hematite film, acting as an intermediary to alleviate the dead layer effect and as a support of large surface areas to coat greater amounts of Fe2O3. The as-prepared photoanodes are notably stable and highly efficient for photoelectrochemical water splitting under visible light. This study provides a facile synthesis process for the controlled production of highly active ultrathin hematite film and a simple route for photocurrent enhancement using several photoanodes in tandem.

Supersaturation-controlled shape evolution of α-Fe2O3 nanocrystals and their facet-dependent catalytic and sensing properties.

Surface engineering of crystals at nanoscale level by precisely and rationally exposing specific facets proved to be highly effective in enhancing the performance of inorganic functional nanocrystals. To do so, a comprehensive understanding of the growth mechanism was of great importance. By using hematite (α-Fe2O3) as an example, in this paper we demonstrated high effectiveness of controlling supersaturation of growth monomers in engineering the exposed facets of nanocrystals. Under surfactant-free hydrothermal conditions, a series of morphology evolution of α-Fe2O3 nanocrystals from {012} faceted pseudocubes to {113} faceted hexagonal bipyramids and {001} faceted nanoplates were successfully activated through concentration-, reaction time-, and solvent-dependent hydrolysis of ferric acetylacetonate. High supersaturation was eventually proven to be conducive to the formation of facets with high surface energy. Furthermore, the α-Fe2O3 nanocrystals enclosed with facets of high surface energy exhibited excellent catalytic activity and gas-sensing ability. The present work will deepen our understanding of thermodynamics and kinetic control over the morphology of nanocrystals as well as our understanding of surface-related performance of inorganic functional nanocrystals.