Solid-state Reaction Conditions Research Articles

Metal-organic framework cobalt gallate derived high-voltage carbon coated lithium cobalt oxide cathode and porous carbon supported cobalt oxide anode materials for superior lithium-ion storage

Exploring innovative green synthesis strategies for both cathode and anode materials with improved lithium-ion storage capabilities is of great importance in developing advanced lithium-ion batteries. In this work, a metal-organic framework (MOF) typed sample cobalt gallate (Co-GA), prepared by the direct redox coprecipitation reaction using gallic acid (GA) molecules and metallic cobalt (Co) foils in mild hydrothermal condition, is employed as a precursor for engineering electrode materials for lithium-ion batteries with high atomic efficiency and low environmental impact. Taking the advantages of the unique microstructure and chemical composition of MOF materials, the Co-GA precursor can be easily converted to a rod-like porous carbon framework confined cobalt oxide nanoparticle anode material (Co3O4/RPC) and a thin carbon layer coated nanosized lithium cobalt oxide (LiCoO2) cathode material (LCO/C), respectively, by simply changing the solid-state reaction conditions. In half-cells with metallic lithium as counter electrode, the LCO/C cathode delivers a stable reversible capacity of 189.33 mAh·g−1 after 100 cycles at 200 mA·g−1 and 128.61 mAh·g−1 after 800 cycles at 1000 mA·g−1 in the voltage range of 3.0–4.6 V, while the Co3O4/RPC anode shows a high reversible capacity of 1081.33 mAh·g−1 after 100 cycles at 200 mA·g−1 and 901.09 mAh·g−1 after 400 cycles at 1000 mA·g−1. This work provides a new perspective for green engineering of both anodic and cathodic materials with enhanced lithium-ion storage performances derived from MOF-typed precursors.

Thermoluminescence properties of K2GdF5:Tb material irradiated in neutron-gamma fields of 241Am-Be source

This paper presents the thermoluminescence properties of K2GdF5:Tb material irradiated in a reference neutron-gamma field and its possibility to be used in neutron dosimetry. Double fluoride of K2GdF5 doped with 10 at% Tb3+ ions was synthesized under solid-state reaction conditions and irradiated in the reference neutron-gamma field of 241Am-Be source. The thermoluminescence glow curves were measured by the Rexon UL-320 TLD reader connected with the WinRex-320 processing program for obtaining the integrated thermoluminescence signals (counts). The results show that the temperature peaks of the irradiated K2GdF5:Tb material concerning the gamma and neutron fields at the distance of 100 cm from the source are at 230?C and 300?C, respectively. The sensitivity ratios of fast-to-thermal neutron and gamma-to-thermal neutron are 6.3 % and 18.2 %, respectively. The batch homogeneity and reproducibility are less than 30 % and 7.5 %, respectively. The linearity is less than 10 % in the dose range of less than 24 mSv. The detection threshold is less than 0.1 mSv, and the fading is 10.7 % after 90 days of irradiation. These thermoluminescence properties of K2GdF5:Tb material considerably satisfy the requirements to be used in neutron dosimetry.

Solid-state reaction synthesis and characterization of Mn-doped LiFePO4 cathode material

Olivine type LiFePO4 has great advantages for Li-ion batteries due to its non-toxicity, high safety, and good cycle life performance. However, its low-rate capability and low energy density make some challenges for this LiFePO4. Several methods like doping with transition metals were used, and Mn ion was used in this work to improve the overall electrochemical properties. LiMn x Fe1-x PO4 is promising cathode material owing to high voltage, structural and chemical stability. However, the electrochemical performance of these materials depends on phases and structures obtained from synthesis. In this work, the effect of solid-state reaction conditions, including calcination temperature and duration, on morphology, structure, and electrochemical properties of LiMn x Fe1-x PO4 cathode materials with the composition of x = 0.5 was investigated. The morphology, crystallography and local structure of the synthesized materials were examined by field emission scanning electron microscope (FE-SEM), X-ray diffractometer (XRD) and Fourier-transform infrared spectrometer (FTIR), respectively. The surface area was also determined by the Brunauer-Emmett-Teller (BET) model. The effect of calcination temperature and reaction time upon the morphology, structures of the synthesized cathode materials were studied and discussed. The results could be essential for further development and employment of LiMn x Fe1-x PO4 in Li-ion batteries.

GAGG:Ce composite scintillator for X-ray imaging

Abstract The paper deals with the development of X-ray imaging composite detectors based on GAGG:Ce powders bound by the organic polysiloxane matrix. The luminescence intensity was improved through optimization of solid state reaction conditions and Ce concentration in GAGG:Ce. The deviation of light output over the detector square does not exceed ±6%. The spatial resolution of 130 μm was achieved with the optimized GAGG:Ce composite detectors.

Solid-state Chemical Reaction Synthesis and Characterization of Lanthanum Tartrate Nanocrystallites Under Ultrasonication Spectra

Under near room temperature, by using sodium tartrate, lanthanum trichloride, lanthanum acetate, and lanthanum nitrate as reactants, we synthesize the lanthanum tartrate nanocrystals in one step under the condition that the infrared lamp is irradiated and the polyethylene glycol 400 is used as the surfactant, where the synthesis method of nanoparticles by solid phase chemical reaction is used. Deionized water after washing with ethanol washes. Tartaric acid lanthanum crystalline powder is gotten, respectively. Analyze solid products phase using X-ray diffraction (XRD) and electron diffraction; characterize the functional groups structure with infrared spectra, and analyzethe change of functional groups in drugs before and after reaction; observe the size, shape, and size distribution of particlesby transmission electron microscopy(TEM). Testing 3 types of tartaric acid crystal powder of lanthanum are nano-crystallization, solid products are granular and relatively uniform in size, with an average particle diameter of about 40 nm, and the yield rate is approximately 92.3%. Furthermore, during the synthesis, the solid-state reaction conditions including raw materials, matching proportion of reactants, additions of inert substance, addition of trace solvents, surfactants and porphyrization time, etc, all have some influence on the morphology, particle size and size distribution of the final products. During the synthesis of the lanthanum tartrate nanocrystallites, the solid state reaction conditions such as changing reactant, matching proportion of reactant, adding inert substance, joining a little solvent or surface active solvent and grinding at different times may influence morphology, particle size and the size distribution of final products.

Phase relations of Li2O–MnO–P2O5 system and the electrochemical properties of Li1+xMn1−xPO4 compounds

The phase relations of Li2O–MnO–P2O5 ternary system under reducing atmosphere have been systematically investigated by means of X-ray diffraction. Inferior to what we expected, no other new lithium manganese phosphates exist within the Li2O–MnO–P2O5 ternary system under the reducing atmosphere. A high-pressure phase Mn3(PO4)2 with graftonite Fe3(PO4)2-type structure can be easily obtained in the MnO–P2O5 system under the ordinary solid-state reaction conditions in H2/Ar atmosphere and its detail structure is presented. In addition, the solid solubility of Li1+xMn1−xPO4 is determined as −0.05⩽x⩽0.03. The lattice parameters and electrochemical properties of Li1+xMn1−xPO4 with x content are investigated. The electrochemical test results show that excess Li-ion (x>0) or the excess Mn-ion (x<0) in LiMnPO4 has an unfavorable effect on the electrochemical properties caused by the deterioration of the lithium diffusion along the one-dimensional tunnels.

Solid State Chemical Reaction Synthesis and Characterization of Nanocrystalline Cerium Carbonate Rare Earth Compound

Under the conditions of the presence of surfactants and ultrasonication, the use of different cerium salt, respectively, with carbonate under solid state chemistry reactions, the synthesis of nanorare earth metal complexes of cerium carbonate crystals was formed. The solid phase was characterized by powder X-ray diffraction (XRD) and electron diffraction (ED). The particle size, its distribution, and morphology of the prepared nanocrystallite were observed by transmission electron microscopy (TEM). The results show that particle sizes are relatively uniform, the morphology of the crystal is spherical, the average particle diameter is about 60 nm, and the yield rate is approximately 93.2%. Furthermore, during the synthesis, the solid-state reaction conditions including raw materials, matching proportion of reactants, additions of inert substance, addition of trace solvents, surfactants and porphyrization time, etc, all have some influence on the morphology, particle size and size distribution of the final products. During the synthesis of the cerium carbonate nanocrystallites, the solid state reaction conditions such as changing reactant, matching proportion of reactant, adding inert substance, joining a little solvent or surface active solvent and grinding at different times may influence morphology, particle size and the size distribution of final products.

LiMn2O4 rods as cathode materials with high rate capability and good cycling performance in aqueous electrolyte

The aqueous lithium–ion batteries using LiMn2O4 as cathode materials are considered to be one of the most promising stationary power sources for large-scale energy storage devices. In the present work, LiMn2O4 rods were successfully synthesized by using hydrothermal reaction to produce β-MnO2 rods as precursor followed by its solid-state lithiation. The influences of the solid-state reaction conditions on the final products were investigated and the electrochemical performances were tested in Li2SO4 aqueous electrolyte. The results show that LiMn2O4 rods can be obtained at 700 °C for 8 h (Sample A) and at 900 °C for 3 h (Sample B), respectively. Sample A exhibits superior electrochemical performances. The discharge capacities are 92.5, 92.9, 93.5 and 96.8 mAh g−1 at 1000, 500, 200 and 100 mA g−1, respectively. They are nearly constant between the high current density of 1000 and 200 mA g−1, demonstrating its high rate capability. In addition, sample A exhibits good cycling performance with only a total capacity loss of 5.4% after 200 cycles.

Solid State Chemical Reaction Synthesis and Characterization of Nanocrystalline Cerium 8-Quinolinolate

Under the conditions of the presence of surfactants and ultrasonication, the use of different cerium salt, respectively, with 8-quinolinolate under solid state chemical reactions, the synthesis of nanorare earth metal complexes of cerium 8-quinolinolate crystals was formed. The solid phase was characterized by powder X-ray diffraction (XRD) and electron diffraction (ED). The particle size, its distribution, and morphology of the prepared nanocrystallite were observed by transmission electron microscopy (TEM). The results show that particle sizes are relatively uniform, the morphology of the crystal is spherical, the average particle diameter is about 30 nm, and the yield rate is approximately 89.9%. Furthermore, during the synthesis, the solid-state reaction conditions including raw materials, matching proportion of reactants, additions of inert substance, addition of trace solvents, surfactants and porphyrization time, etc, all have some influence on the morphology, particle size and size distribution of the final products. During the synthesis of the cerium 8-quinolinolate nanocrystallites, the solid state reaction conditions such as changing reactant, matching proportion of reactant, adding inert substance, joining a little solvent or surface active solvent and grinding at different times may influence morphology, particle size and the size distribution of final products.

Solid-State Chemical Reaction Synthesis and Characterization of Nanocrystalline CePO&lt;sub&gt;4&lt;/sub&gt; under Ultrasonication Spectra

Under the conditions of the presence of surfactants and ultrasonication, the use of different cerium salt, respectively, with phosphate under solid state chemistry reactions, the synthesis of nano-rare earth metal complexes of CePO4 crystals was formed. The solid phase was characterized by powder X-ray diffraction and electron diffraction. The particle size, its distribution, and morphology of the prepared nanocrystallite were observed by transmission electron microscopy. The results show that particle sizes are relatively uniform, the morphology of the crystal is spherical, the average particle diameter is about 50 nm, and the yield rate is approximately 92.8%. Furthermore, during the synthesis, the solid-state reaction conditions including raw materials, matching proportion of reactants, additions of inert substance, addition of trace solvents, surfactants and porphyrization time, etc, all have some influence on the morphology, particle size and size distribution of the final products. During the synthesis of the nanocrystalline CePO4, the solid state reaction conditions such as changing reactant, matching proportion of reactant, adding inert substance, joining a little solvent or surface active solvent and grinding at different times may influence morphology, particle size and the size distribution of final products.

Solid State Chemical Reaction Synthesis and Characterization of Nanocrystalline Cerium Oxalate under Ultrasonication Spectra

Under the conditions of the presence of surfactants and ultrasonication, the use of different cerium salt, respectively, with oxalic acid under solid state chemistry reactions, the synthesis of nano-rare earth metal complexes of cerium oxalate crystals was formed. The solid phase was characterized by powder X-ray diffraction (XRD) and electron diffraction (ED). The particle size, its distribution, and morphology of the prepared nanocrystallite were observed by transmission electron microscopy (TEM). The results show that particle sizes are relatively uniform, the morphology of the crystal is spherical, the average particle diameter is about 40 nm, and the yield rate is approximately 91.6%. Furthermore, during the synthesis, the solid-state reaction conditions including raw materials, matching proportion of reactants, additions of inert substance, addition of trace solvents, surfactants and porphyrization time, etc, all have some influence on the morphology, particle size and size distribution of the final products. During the synthesis of the cerium oxalate nanocrystallines, the solid state reaction conditions such as changing reactant, matching proportion of reactant, adding inert substance, joining a little solvent or surface active solvent and grinding at different times may influence morphology, particle size and the size distribution of final products.

Texture evolution and its effects on growth of intermetallic compounds formed at eutectic Sn37Pb/Cu interface during solid-state aging

The growth orientation of Cu6Sn5 intermetallic compounds (IMCs) formed at the eutectic Sn37Pb/polycrystalline Cu interface during solid-state aging was investigated. The results indicate that the interfacial Cu6Sn5 grains exhibit textured growth under solid-state conditions, and their preferred orientations are affected by the initial joint preparation conditions. Cu6Sn5 grains in the [0001] direction normal to the interface are stable in solid and molten Sn37Pb solder at 200°C, but are rapidly consumed at 280°C. This effect leads to the formation of different textures in the Cu6Sn5 layer during the solid-state aging treatment of joints formed at 200 and 280°C. In addition, the influence of texture evolution on the growth of interfacial IMCs was evaluated. The results indicate that Sn diffusion is faster along the [0001] direction of the Cu6Sn5 crystal than along an angle of 25–45° to the [0001] direction; therefore, more IMCs are generated at the interface of the joints formed at 200°C than at those formed at 280°C under the same solid-state reaction conditions.

Enhanced luminescence and degradation resistance in Tb modified Yttrium Borate core–nano silica shell phosphor under UV and VUV excitation

Composition variation in optimized solid state reaction conditions has been done to achieve intense green emission in YTb x BO 3 phosphor under UV and VUV (147 nm resonant Xe*, 172 nm Xe 2* excimer band) excitation. Inert interface layer created by fabricating a shell of silica nanoparticles over individual phosphor grain protected the phosphor surface from deterioration and oxidation of luminescent ion (Tb 3+) thus completely arresting phosphor degradation. At optimum Tb content of 20 mol%, integrated photoluminescence intensity of developed YTb x BO 3 phosphor is four times higher than commercial green YBT. With short decay time of 4 ms, YTb x BO 3 core–nano silica shell green emitting phosphor has great application potential in PDP panel and phosphor coated Xe lamps.

Ultrasonication solid state chemical reaction synthesis and characterization of nanocrystalline Zn(Oxin) 2·2H 2O (zinc 8-quinolinolate)

Under near ambient temperature and ultrasonication, nanocrystalline Zn(Oxin) 2·2H 2O (zinc 8-quinolinolate) was synthesized by solid state chemical reaction. The particle size distribution was relatively uniform, the morphology of the mare was ball like particle. The phase, particle size and morphology of the prepared nanocrystalline were characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM) and electron diffraction (ED). The results show that the crystallite product has an average size of about 30 nm. The effects of a series of reaction conditions on the synthesis of Zn(Oxin) 2·2H 2O by solid state reaction were studied. During the synthesis of nanocrystalline Zn(Oxin) 2·2H 2O, the solid state reaction conditions such as changing reactant, matching proportion of reactant, adding inert substance, joining a little solvent or surface active solvent and grinding at different times may influence morphology, particle size and the size distribution of final products.

Enzymatic modification to improve the water-absorbing and gelling properties of psyllium

Psyllium husks were treated with a commercial food-grade polysaccharidase mixture, under solid-state reaction conditions, to improve water-absorbing and gelling properties. The modified psyllium preparations were analyzed and compared to the original psyllium and the control, treated with no enzyme under the same reaction conditions, for their water-absorbing ability, gelling properties, fibre contents, and surface structures. The water-absorbing ability was determined by a gravimetric method, while the gelling property of the modified psyllium was measured using a texture analyzer. The results showed that the solid-state enzymatic modification was able to significantly reduce both water-absorbing and gelling abilities of psyllium. Compared to the control, reductions of 49% in water-absorbing ability, 71% in gel hardness, and 35% in gel adhesiveness were observed for the novel psyllium preparation that was treated with the enzyme mixture at a level of 36 units/g psyllium. The surface structure of the modified psyllium was examined using scanning electron microscopy (SEM). The SEM results showed that the enzymatic modification decreased the total surface area. This may contribute to the reduced water-absorbing ability of the modified psyllium. This study demonstrated the potential of preparing novel psyllium preparations, using a solid-state enzymatic method, for commercial food applications.

Effects of solid-state enzyme treatments on the water-absorbing and gelling properties of psyllium

Psyllium husks were treated with commercial food grade enzymes under solid-state reaction conditions to improve their water-absorbing and gelling properties. The modified psyllium preparations were analyzed and compared to the original psyllium and the control, treated with no enzyme under the same reaction condition, for their water-absorbing ability, gelling capacity, surface structures, and fiber contents. The results showed that the solid-state enzymatic modification was able to reduce both water-absorbing and gelling abilities of psyllium with a slight reduction in soluble fiber content. Scanning electron microscopy measurements showed that the enzymatic modification decreased the total surface area. This may contribute to the reduced water-absorbing ability of the modified psyllium. The solid-state enzymatic procedure requires neither special equipment nor additional steps to remove moisture after inactivating the enzymes and generates no chemical waste. This study demonstrated the potential of preparing novel psyllium preparations with improved gelling and water-absorbing properties using a solid-state enzymatic method for commercial food applications.

Solid-State [4 + 2] Cycloaddition of Fullerene C(60) with Condensed Aromatics Using a High-Speed Vibration Milling Technique.

The solid-state reaction using a high-speed vibration milling (HSVM) technique has been applied to the [4 + 2] cycloaddition of fullerene C(60) with condensed aromatics such as anthracenes, tetracene, pentacene, and naphtho[2,3-a]pyrene. From the reaction with anthracene, [4 + 2] cycloadduct 1 was obtained in better yield than the reaction in solution. Despite such heterogeneous solid-state reaction conditions, an equilibrium state appears to be attained between the reactants (C(60) and anthracene) and products (mono- and bisadducts) since essentially the same product mixture was obtained starting either from the reactants or from the monoadduct after 30 min of the HSVM reaction. The reaction with pentacene gave double C(60) adduct 4 with two C(60) cages attached to a pentacene molecule, which cannot be obtained in the reaction in toluene solution, in addition to symmetrical monoadduct 3. The HSVM treatment of C(60) with 9,10-dimethylanthracene, tetracene, or naphtho[2,3-a]pyrene also gave the corresponding [4 + 2] cycloadducts in fair yields. The redox properties of these adducts were investigated by the use of cyclic voltammetry.

ＢＰＳＣＣＯ系酸化物超電導体の組成比による特性変化

A relationship between X-ray powder diffraction pattern and superconducting characteristics has been systematically investigated with respect to Bi-Pb-Sr-Ca-Cu superconducting oxides. The starting composition ratio was changed to obtain an optimum high-Tc single phase. At a composition ratio of Bi1.85Pb0.35Sr1.9Ca2Cu3.2, a pure high-Tc phase was obtained in the X-ray diffraction pattern and ac susceptibility measurement, although the temperature-resistivity (T-R) characteristics was a mixing of two phases with the low-Tc and high-Tc. On the contrary, at a composition of Bi1.85Pb0.35Sr2.2Ca2 Cux(X=3.3, 3.4), a simple single phase pattern with Tc (end) at 107k was observed in its T-R characteristics, despite the fact that this composition give a mixed phase in its X-ray diffraction and ac susceptibility measurement. The zero resistance transition temperature is more sensitive to Sr molar ratio than to Cu molar ratio. Thus, under the solid-state reaction conditions of the present study, ther molar ratio of Sr play an important role for forming a large quantity of high-Tc crystal phase grain with such thin grain boundaries as to connect the high-Tc phase grains electrically.