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FeCl3 is Bismuth triodide structured and crystallizes in the trigonal R-3 space group. The structure is two-dimensional and consists of three FeCl3 sheets oriented in the (0, 0, 1) direction. Fe3+ is bonded to six equivalent Cl1- atoms to form edge-sharing FeCl6 octahedra. All Fe–Cl bond lengths are 2.27 Å. Cl1- is bonded in a water-like geometry to two equivalent Fe3+ atoms.
FeCl3 crystallizes in the triclinic P1 space group. The structure is one-dimensional and consists of one FeCl3 ribbon oriented in the (1, 0, 0) direction. there are two inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to five Cl1- atoms to form corner-sharing FeCl5 trigonal bipyramids. There are a spread of Fe–Cl bond distances ranging from 2.13–2.30 Å. In the second Fe3+ site, Fe3+ is bonded in a distorted see-saw-like geometry to four Cl1- atoms. There are a spread of Fe–Cl bond distances ranging from 2.10–2.21 Å. There are six inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one Fe3+ atom. In the second Cl1- site, Cl1- is bonded in an L-shaped geometry to two Fe3+ atoms. In the third Cl1- site, Cl1- is bonded in a single-bond geometry to one Fe3+ atom. In the fourth Cl1- site, Cl1- is bonded in a single-bond geometry to one Fe3+ atom. In the fifth Cl1- site, Cl1- is bonded in an L-shaped geometry to two Fe3+ atoms. In the sixth Cl1- site, Cl1- is bonded in a bent 120 degrees geometry to two equivalent Fe3+ atoms.
FeCl3 crystallizes in the triclinic P1 space group. The structure is one-dimensional and consists of two FeCl3 ribbons oriented in the (1, 0, 0) direction. Fe3+ is bonded to four Cl1- atoms to form corner-sharing FeCl4 tetrahedra. There are a spread of Fe–Cl bond distances ranging from 2.14–2.36 Å. There are three inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one Fe3+ atom. In the second Cl1- site, Cl1- is bonded in a water-like geometry to two equivalent Fe3+ atoms. In the third Cl1- site, Cl1- is bonded in a single-bond geometry to one Fe3+ atom.
FeCl3 is Aluminum trichloride-like structured and crystallizes in the trigonal P-3 space group. The structure is two-dimensional and consists of twelve FeCl3 sheets oriented in the (0, 0, 1) direction. Fe3+ is bonded to six Cl1- atoms to form edge-sharing FeCl6 octahedra. There are three shorter (2.40 Å) and three longer (2.41 Å) Fe–Cl bond lengths. There are two inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in an L-shaped geometry to two equivalent Fe3+ atoms. In the second Cl1- site, Cl1- is bonded in an L-shaped geometry to two equivalent Fe3+ atoms.
Carbon materials containing iron alloy, iron metal, iron oxide or iron halide were fabricated. Typical samples of these metals were estimated to contain 1 iron atom per 3.5 to 5 carbon atoms. Those carbon materials containing iron alloy, iron metal, and/or Fe3O4 were magnetic. The kinetics of the fabrication process were studied by exposing graphite fluoride (CF(0.68)) to FeCl3 over a 280 to 420 C temperature range. Between 280 and 295 C, FeCl3 quickly entered the structure of CF(0.68), broke the carbon-fluorine bonds, and within 10 to 30 min, completely converted it to carbon made up of graphite planes between which particles of crystalline FeF3 and noncrystalline FeCl3 were located. Longer reaction times (e.g., 28 hr) or higher reaction temperatures (e.g., 420 C) produced materials containing graphite, a FeCl3-graphite intercalation compound, FeCl2(center dot)4H2O, and FeCl2(center dot)2H2O. These products were further heat treated to produce iron-containing carbon materials. When the heating temperature was kept in the 750 to 850 C range, and the oxygen supply was kept at the optimum level, the iron halides in the carbon structure were converted to iron oxides. Raising the heat to temperatures higher than 900 C reduced such iron oxides to iron metal. The kinetics of these reactions were used to suggest processes for fabricating carbon materials containing iron alloy. Such processes were then tested experimentally. In one of the successful trial runs, commercially purchased CF(0.7) powder was used as the reactant, and NiO was added during the final heating to 1200 C as a source of both nickel and oxygen. The product thus obtained was magnetic and was confirmed to be a nickel-iron alloy in carbon.
(FeCl3)2N2 crystallizes in the hexagonal P6_3/mmc space group. The structure is one-dimensional and consists of two ammonia molecules and one FeCl3 ribbon oriented in the (0, 0, 1) direction. In the FeCl3 ribbon, Fe2+ is bonded to six equivalent Cl1- atoms to form face-sharing FeCl6 octahedra. All Fe–Cl bond lengths are 2.25 Å. Cl1- is bonded in a distorted L-shaped geometry to two equivalent Fe2+ atoms.
Biobased foams have the potential to serve as eco-friendly alternatives to petroleum-based foams, provided they achieve comparable thermomechanical and physical properties. We propose a facile approach to fabricate eco-friendly cellulose nanofibril (CNF)-reinforced thermomechanical pulp (TMP) fiber-based foams via an oven-drying process with thermal conductivity as low as 0.036 W/(m·K) at a 34.4 kg/m3 density. Acrodur®, iron chloride (FeCl3), and cationic polyacrylamide (CPAM) were used to improve the foam properties. Acrodur® did not have any significant effect on the foamability and density of the foams. Mechanical, thermal, cushioning, and water absorption properties of the foams were dependent on the density and interactions of the additives with the fibers. Due to their high density, foams with CPAM and FeCl3 at a 1% additive dosage had significantly higher compressive properties at the expense of slightly higher thermal conductivity. There was slight increase in compressive properties with the addition of Acrodur®. All additives improved the water stability of the foams, rendering them stable even after 24 h of water absorption.
Carbon fibers containing ferromagnetically-ordered iron or other transition metals could be used in a variety of lightweight magnetic composites. Intercalation of bulk graphite with CoCl2 or FeCl3, followed by reduction with butyl lithium, did indeed produce magnetic samples; however, the observed room temperature permeabilities (mu) were less than 2 G/Oe. Magnetic data are presented on carbon fibers containing large amounts of elemental iron, which were prepared by a new method. In this method Amoco P-75 fibers were intercalated with Br2 and I2 followed by fluorination, forming CF(0.75). This product was then intercalated with FeCl3. Subsequent heat treatments in oxidizing and reducing atmospheres converted most of the iron to the pure alpha phase. Room temperature permeabilities as large as 40 G/Oe are observed.
Sodium fluoride (NaF) has been found to be an activation agent in exfoliating a hexagonal boron nitride (hBN) platelet, using solvent free method. The procedure was carried out by enhancing the intercalation of ferric chloride (FeCl3) in an intermediate step, up to 330 °C, followed by removal of the by-product at room temperature. In this research, five additional common salts including lithium fluoride, potassium fluoride, lithium chloride, sodium chloride, and potassium chloride, were examined and compared to NaF for their effectiveness in producing the most exfoliation of a commercially available sub-micron-size hBN. It was found that, all fluoride and chloride salts significantly activated the intercalation of FeCl3 into this hBN. Analyses and characterization from X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy and Raman spectroscoy revealed NaCl to be one of most effective agents without further heat treatment and the least expensive salt in the intercalating reaction and exfoliation process. The synthetic route of this solvent free method is straightforward with 89% yield and above which can be produced on a large scale.
Fe-modified biochars (FeBC) are effective antimony (Sb) removal materials; however, the removal mechanisms require further investigation. In this study, aqueous Sb(III) and Sb(V) removal by FeBC (300, 600, and 900 °C) was evaluated, with the adsorption mechanisms investigated using X-ray absorption spectroscopy (XAS). Screening results (based on removal efficiencies) using different types of FeBC indicated the 900 °C FeCl3- modified biochar (FeCl3BC900) achieved the best Sb(III/V) removal performance. The kinetics of the Sb(III/V) removal process were best fitted by a pseudo-second-order model. Additionally, the isothermal results were described by Langmuir and Redlich-Peterson models. Aqueous analysis and X-ray absorption near-edge structure data fitting indicated Sb(III) was oxidized to Sb(V) in the Sb(III)-spiked system, and the oxidation extent increased with increasing pyrolysis temperature. The oxidation process rapidly occurred in both the solution and biochar. No Sb(V) was reduced to Sb(III) in the Sb(V)-spiked system. The XAS results of the isothermal experiment indicated the oxidation capacity of FeCl3BC900 was limited for high initial Sb(III) concentrations. The SbFe1 and Sb-Fe2 bonding distances were 3.05–3.10 and 3.47–3.54 Å, respectively, indicating inner-sphere complexes were formed during the Sb(III/V) removal processes. The Sb(III/V) removal mechanisms included electrostatic adsorption, inner-sphere complexes, and coprecipitation. Oxidation was also involved in Sb(III) removal.
Low-cost and efficient oxygen reduction reaction (ORR)/oxygen evolution reaction (OER) bifunctional electrocatalysts are vital for the applications of rechargeable Zn-air batteries (ZABs). Given the high catalytic activity of single-atom catalysts (SACs), preparing SACs on a large scale for ZABs is desirable but remains challenging. Herein, in situ formation of single-atom Fe-N-C catalysts on plate wood-based porous carbon is achieved via a facile Lewis acid pretreatment and carbonization process. Lewis acid FeCl3 pretreatment on the cell wall of wood not only produces abundant microchannels but also successfully introduces atomically dispersed Fe-N active species into the hierarchical structure. Such uniformly dispersive SACs on the hierarchical structure enhance the ORR/OER performance and durability. A ZAB using the catalyst in the cathode shows a high power density (70.2 mW cm -2 , at quasi solid state) and long-term stability. This work provides a new path for the large-scale preparation of high-performance SACs.
Spiral spin liquids are correlated paramagnetic states with degenerate propagation vectors forming a continuous ring or surface in reciprocal space. On the honeycomb lattice, spiral spin liquids present a novel route to realize emergent fracton excitations, quantum spin liquids, and topological spin textures, yet experimental realizations remain elusive. Here, using neutron scattering, we show that a spiral spin liquid is realized in the van der Waals honeycomb magnet FeCl3. A continuous ring of scattering is directly observed, which indicates the emergence of an approximate U(1) symmetry in momentum space. Our work demonstrates that spiral spin liquids can be achieved in two-dimensional systems and provides a promising platform to study the fracton physics in spiral spin liquids.
FeCl3(NS)4 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four 1,3,5,7,2,4,6,8-tetrathiatetrazocane molecules and four iron trichloride molecules.
FeCl3(NS)4 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four 1,3,5,7,2,4,6,8-tetrathiatetrazocane molecules and four iron trichloride molecules.
Experimental anion permselective membranes were prepared and tested for their suitability as cell separators in a chemical redox power storage system being developed at NASA-Lewis Research Center. The goals of long-term (1000 hr) oxidative and thermal stability at 80 C in FeCl3 and CrCl3 electrolytes were met by most of the weak base and strong base amino exchange groups considered in the program. Good stability is exhibited by several of the membrane substrate resins. These are 'styrene' divinylbenzene copolymer and PVC film. At least four membrane systems produce strong flexible films with electrochemical properties (resistivity, cation transfer) superior to those of the 103QZL, the most promising commercial membrane. The physical and chemical properties of the resins are listed.
Potentiostatic determinations in various mixtures of FeCl2-FeCl3 with excess HCl show rest potentials that are 0.1 V less electropositive than the theoretical values from the formulated ratios of FeII to FeIII (probably as a result of complexing). The standard rate constant sub s. ranges between 0.0001 and 0.000 cm/sec. Tafel slopes b of roughly 0.12V per decade indicate single-electron exchange kinetics. No significant trend in either b or sub s was attributed to mixture composition. The higher sub s. values occurred with and edge-on pyrolytic graphite that had undergone a permanent surface change.
Results are reported for measurements of the widths and shifts of the overlapping helium-broadened profiles of the Fe I absorption lines at 3719.94 and 3722.56 A, which were performed in a ballistic piston compressor using a saturated solution of FeCl3 in ethanol. It is found that at 4000 K, the 3719.94-A line has a gamma/n (FWHM) value of approximately 5.2 billionths rad/sec per cu cm, the blue shift of this line corresponds to a beta/n value of about 0.49 billionth rad/sec per cu cm, and the 3722.56-A line has the same values. These results are compared with previous experimental determinations and with theoretical calculations of neutral-line broadening for the Fe I lines. The significance of these measurements with respect to the solar spectrum and cool DG white dwarfs is discussed.
Based on considerations of principles and experimental data, the interference of sulfate ions in poteniometric titration of EDTA with FeCl3 was confirmed. The method of back complexometric titration of molybdenum of Nonova and Gasheva was improved by replacing hydrazine sulfate with hydrazine hydrochloride for reduction of Mo(VI) to Mo(V). The method can be used for one to tenths of mg of molybdenum with 0.04 mg standard deviation. The specific method of determination of molybdenum in molybdenite concentrates is presented.