6047-25-2Relevant articles and documents
Concerning the cation distribution in MnFe2O4 synthesized through the thermal decomposition of oxalates
Gabal,Ata-Allah
, p. 995 - 1003 (2004)
A single phase manganese ferrite powder have been synthesized through the thermal decomposition reaction of MnC2O4·2H 2O-FeC2O4·2H2O (1:2 mole ratio) mixture in air. DTA-TG, XRD, Mo?ssbauer spectroscopy, FT-IR and SEM techniques were used to investigate the effect of calcination temperature on the mixture. Firing of the mixture in the range 300-500 °C produce ultra-fine particles of α-Fe2O3 having paramagnetic properties. XRD, Mo?ssbauer spectroscopy as well as SEM experiments showed the progressive increase in the particle size of α-Fe2O 3 up to 500 °C. DTA study reveals an exothermic phase transition at 550 °C attributed to the formation of a Fe2O 3-Mn2O3 solid solution which persists to appear up to 1000 °C. At 1100 °C, the single phase MnFe 2O4 with a cubic structure predominated. The Mo?ssbauer effect spectrum of the produced ferrite exhibits normal Zeeman split sextets due to Fe3+ions at tetrahedral (A) and octahedral (B) sites. The obtained cation distribution from Mo?ssbauer spectroscopy is (Fe0.92Mn0.08)[Fe1.08Mn0.92]O 4.
Biomimetic control of iron oxide and hydroxide phases in the iron oxalate system
Molinier, Michel,Price, Daniel J.,Wood, Paul T.,Powell, Annie K.
, p. 4061 - 4068 (1997)
The syntheses of mineral phases of iron formed under hydrolytic conditions have been studied using ambient and hydrothermal methods in the presence and absence of the oxalate (ox) template. A systematic survey of experimental parameters revealed how the oxolate template can influence crystal morphology, iron oxidation state and the nature of the phase formed. In addition to observing biomimetic control over crystal morphology of magnetite, two iron(II) hydrolytic oxalate phases were observed, humboldtine, FeII(ox)(H2O)2, and the new phase, FeII2(ox)(OH)2, which was identified by single-crystal X-ray diffraction.
Cation-substituted LiFePO4 prepared from the FeSO4·7H2O waste slag as a potential Li battery cathode material
Wu, Ling,Wang, Zhixing,Li, Xinhai,Guo, Huajun,Li, Lingjun,Wang, Xiaojuan,Zheng, Junchao
, p. 278 - 284 (2010)
The purpose of this study is to utilize the huge FeSO4·7H2O waste slag produced by the titanium dioxide industry. FeC2O4·2H2O precursors are synthesized at various pH values by using the waste slag and H2C2O4·2H2O as raw materials, and without any purifying process. ICP analysis confirms that the impurity content of FeC2O4·2H2O increases with the pH value. Crystalline cation-substituted LiFePO4 are prepared from the FeC2O4·2H2O precursors. The cation dopants do not obviously change the structure of LiFePO4, and all the samples are single olivine-type phase and well crystallized. The lattice parameters of LiFePO4 decrease with the increased dopants contents. The dopants limit the size of LiFePO4 nanocrystals, LiFePO4 particles agglomeration and, consequently, improve the electrochemical performance of LiFePO4. The cation-substituted LiFePO4 prepared from the waste slag show much better electrochemical properties than the pure LiFePO4 at high current rates. The optimal pH value for synthesizing FeC2O4·2H2O from the waste slag is about 1.0, with 96.6% iron recovery. The cation-substituted LiFePO4 prepared from this precursor exhibits the best electrochemical properties, which delivers a capacity of 152, 142 and 126 mAh g-1 at 1C, 2C and 5C rate, respectively, and shows excellent cycling performance.
Polymorphism and variable structural dimensionality in the iron(III) phosphate oxalate system: A new polymorph of 3D [Fe2(HPO 4)2(C2O4)(H2O) 2]·2H2O and the layered ma
Lethbridge, Zoe A. D.,Clarkson, Guy J.,Turner, Scott S.,Walton, Richard I.
, p. 9176 - 9182 (2009)
Two new iron (III) phosphate oxalates have been isolated under hydrothermal conditions as phase-pure samples and their crystal structures determined from single crystal X-ray diffraction. [Fe2(HPO4) 2(C2O4
The low temperature synthesis of metal oxides by novel hydrazine method
Rane,Uskaikar,Pednekar,Mhalsikar
, p. 627 - 638 (2007)
The hydroxide, oxalate and citrate precursors of the metal oxides such as γ-Fe2O3, (MnZn)Fe2O4, Cu(K)Fe2O4, BaTiO3, La(Sr)MnO3, La(Sr)AlO3, La/Gd(Ca/Ba/Sr)C
X-ray diffraction and Mossbauer studies of the (Fe1-xNix)4N compounds (0 ≤ x ≤ 0.5)
Li,Yang,Xue,Zhou
, p. 221 - 224 (1995)
X-ray diffraction and Mossbauer spectroscopy studies on the γ-Fe4N type (Fe1-xNix)4N compounds (0 ≤ x ≤ 0.5) were performed. The lattice constants decrease with increasing x. Compared with Fe1-xNisub
Large-scale fabrication of porous carbon-decorated iron oxide microcuboids from Fe-MOF as high-performance anode materials for lithium-ion batteries
Li, Minchan,Wang, Wenxi,Yang, Mingyang,Lv, Fucong,Cao, Lujie,Tang, Yougen,Sun, Rong,Lu, Zhouguang
, p. 7356 - 7362 (2015)
A facile, cost-effective and environmentally friendly route has been developed to synthesise porous carbon-decorated iron oxides on a large scale via annealing iron metal-organic framework (MOF) precursors. The as-prepared C-Fe3O4 particles exhibit microcuboid-like morphologies that are actually composed of ultrafine nanoparticles and show a greatly enhanced lithium storage performance with high specific capacity, excellent cycling stability and good rate capability. The C-Fe3O4 electrodes demonstrate a high reversible capacity of 975 mA h g-1 after 50 cycles at a current density of 100 mA g-1 and a remarkable rate performance, with capacities of 1124, 1042, 886 and 695 mA h g-1 at current densities of 100, 200, 500 and 1000 mA g-1, respectively. The satisfactory electrochemical performance was attributed to the hierarchical architecture, which benefitted from the synergistic effects of the high conductivity of the carbon matrix, the cuboid-like secondary particles on the microscale, and the ultrafine primary nanoparticles on the nanoscale. This low-cost and simple method provides the possibility to prepare anode materials on a large scale and hence may have great potential applications in energy storage and conversion. This journal is
Na2Fe(C2O4)F2: A New Iron-Based Polyoxyanion Cathode for Li/Na Ion Batteries
Yao, Wenjiao,Sougrati, Moulay-Tahar,Hoang, Khang,Hui, Jianing,Lightfoot, Philip,Armstrong, A. Robert
, p. 2167 - 2172 (2017)
A new mixed anion compound, Na2Fe(C2O4)F2, has been prepared by hydrothermal synthesis. The crystal structure exhibits infinite chains of corner-linked FeII-centered octahedra, with coordination composed of both oxalate and fluoride ligands. This compound exhibits promising reversible lithium and sodium insertion. On extended cycling, Na2Fe(C2O4)F2 is capable of reversibly inserting 0.67 Li+ or 0.56 Na+ per formula unit up to 50 cycles at the average discharge voltages of 3.3 and 3.0 V, respectively. This represents arguably the best performance as a prospective cathode material so far observed among oxalates and is comparable to many known iron phosphate-based cathode materials.
Local magnetic moments in the (Fe1-xNix)4N (0 ≤ x ≤ 0.6) compounds
Yang, Jinbo,Xue, Desheng,Li, Fashen
, p. 2781 - 2785 (1997)
Moessbauer and magnetic measurements have been performed on the single-phase γ′-Fe4N and (Fe1-xNix)4N compounds. The local magnetic moments of iron and nickel atoms are evaluated by combining hyperfine fields an
Structure characterization of several oxalate-bridged transition-metal coordination polymers
Yu, Jie-Hui,Hou, Qin,Bi, Ming-Hui,Lü, Zheng-Liang,Zhang, Xiao,Qu, Xue-Jian,Lu, Jing,Xu, Ji-Qing
, p. 69 - 73 (2006)
Four oxalate-bridged transition-metal supramolecular compounds [Co2(im)4(ox)2] 1, [Co(im)2(ox)] 2, [Mn(2,2′-bpy)(ox)] 3 and [Fe(H2O)2(ox)] 4 (im, imidazole; ox, oxalate; bpy, bipyridine) we
