Synthesis of LiFePO4 Cathode Materials by a Chemical Method

2011 ◽  
Vol 197-198 ◽  
pp. 1049-1052
Author(s):  
Yuan Sun ◽  
Xiu Juan Zhao ◽  
Guo Jun Li ◽  
Rui Ming Ren

The olivine-type LiFePO4powder was prepared by a chemical method using the synthesized FePO41.78H2O, LiOH, citric acid and PEG as raw materials. The synthesized FePO41.78H2O precursor powder was obtained by co-precipitation method. LiFePO4powder was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and thermo-gravimetric analysis (TGA)/differential scanning calorimetry (DSC). The results showed that the calcined LiFePO4was in a single phase when fabricated by using the synthesized FePO41.78H2O powder at pH of 3.5 in argon atmosphere.

2015 ◽  
Vol 1112 ◽  
pp. 489-492
Author(s):  
Ali Mufid ◽  
M. Zainuri

This research aims to form particles of hematite (α-Fe2O3) with a basis of mineral iron ore Fe3O4 from Tanah Laut. Magnetite Fe3O4 was synthesized using co-precipitation method. Further characterization using X-ray fluorescence (XRF) to obtain the percentage of the elements, obtained an iron content of 98.51%. Then characterized using thermo-gravimetric analysis and differential scanning calorimetry (TGA-DSC) to determine the calcination temperature, that at a temperature of 445 °C mass decreased by 0.369% due to increase in temperature. Further Characterization of X-ray diffraction (XRD) to determine the phases formed at the calcination temperature variation of 400 °C, 445 °C, 500 °C and 600 °C with a holding time of 5 hours to form a single phase α-Fe2O3 hematite. Testing with a particle size analyzer (PSA) to determine the particle size distribution, where test results indicate that the α-Fe2O3 phase of each having a particle size of 269.7 nm, 332.2 nm, 357.9 nm, 412.2 nm. The best quantity is shown at a temperature of 500 °C to form the hematite phase. This result is used as the calcination procedure to obtain a source of Fe ions in the manufacture of Lithium Ferro Phosphate.


2011 ◽  
Vol 675-677 ◽  
pp. 57-60
Author(s):  
Yuan Sun ◽  
Xiu Juan Zhao ◽  
Rui Ming Ren

The olivine-type LiFePO4 powder was prepared by a chemical method using the synthesized FePO4⋅2H2O, LiOH and glucose as raw materials. The synthesized FePO4⋅2H2O powder was obtained by co-precipitation method. FePO4⋅2H2O and LiFePO4 powders were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results showed the synthesized FePO4⋅2H2O powder at pH of 2.05 was in a single phase and nearly spherical in shape. Using the synthesized powders to prepared LiFePO4 at 600 °C in vacuum for 2 h was nearly spherical in shape and whose size was in the range of 0.1-0.5μm.


2014 ◽  
Vol 852 ◽  
pp. 304-308
Author(s):  
Guo Liang Dai ◽  
Hong Xiao ◽  
Shi Feng Zhu ◽  
Mei Wu Shi

Electron beam irradiation cross-linking of polyvinyl alcohol (PVA) films with the presence of N, N'- methylene bisacrylamide (MBA) were studied, improving the thermal stability. The films unirradiated and irradiated were characterized by ATR-FTIR spectroscopy, X-ray diffraction, differential scanning calorimetry and thermo gravimetric analysis. The PVA films with the presence of MBA would crosslink after irradiation. The crystallinity increased firstly and then decreased as a function of irradiation dose, while the melting temperature decreased with increasing the dose. Beside, the T30%, T50%, T90% and Tmax temperature of degradation increased as the irradiation dose increased.


Author(s):  
X. S. Gama

In deciding the workable layout of any network an appropriate technology plays a major role and can improve accuracy and flexibility efficiently, if chosen and implemented in best possible way. The growth in the infrared applications has created a need for knowledge of its optical characteristics in the spectral region for the purpose of designing. Very little work is previously reported in natural oil doped PVA membranes. In this work, a simple attempt is made synthesize and characterize the wintergreen oil and basil oil doped PVA membranes. In investigation, basil oil and wintergreen oil doped PVA membranes were prepared and is made to characterize. The resulting membranes were characterized by Fourier transform infrared spectroscopy (FTIR), wide-angle X-ray diffraction (WXAD), thermo-gravimetric analysis (TGA) and differential scanning Calorimetry (DSC).


Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1712
Author(s):  
Appusamy Muthukrishnaraj ◽  
Salma Ahmed Al-Zahrani ◽  
Ahmed Al Otaibi ◽  
Semmedu Selvaraj Kalaivani ◽  
Ayyar Manikandan ◽  
...  

Towards the utilization of Cu2O nanomaterial for the degradation of industrial dye pollutants such as methylene blue and methyl orange, the graphene-incorporated Cu2O nanocomposites (GCC) were developed via a precipitation method. Using Hummers method, the grapheme oxide (GO) was initially synthesized. The varying weight percentages (1–4 wt %) of GO was incorporated along with the precipitation of Cu2O catalyst. Various characterization techniques such as Fourier-transform infra-red (FT-IR), X-ray diffraction (XRD), UV–visible diffused reflectance (UV-DRS), Raman spectroscopy, thermo gravimetric analysis (TGA), energy-dispersive X-ray analysis (EDX), and electro chemical impedance (EIS) were followed for characterization. The cabbage-like morphology of the developed Cu2O and its composites were ascertained from field-emission scanning electron microscopy (FESEM) and high-resolution transmission electron microscopy (HR-TEM). In addition, the growth mechanism was also proposed. The results infer that 2 wt % GO-incorporated Cu2O composites shows the highest value of degradation efficiency (97.9% and 96.1%) for MB and MO at 160 and 220 min, respectively. Further, its catalytic performance over visible region (red shift) was also enhanced to an appreciable extent, when compared with that of other samples.


2016 ◽  
Vol 30 (32n33) ◽  
pp. 1650347
Author(s):  
Amarjeet ◽  
Vinod Kumar

[Formula: see text] ([Formula: see text] = 0.1, 0.3 and 0.5) nanoparticles were prepared by chemical co-precipitation method. The developed nanoparticles were characterized for structural properties by powder X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) techniques. Peak position in the X-ray diffraction pattern confirmed the single spinel phase of the developed particles. Infrared (IR) spectroscopy in mid-IR range showed the presence of characteristic absorption bands corresponding to octahedral and tetrahedral bonds in the spinel structure of prepared samples. Thermo-gravimetric analysis (TGA) measurements showed a considerable weight loss in the developed samples above 700[Formula: see text]C. Frequency dependence of the electrical properties of the developed material pellets was studied in the frequency range of 1 kHz–5 MHz. Temperature dependence of the dielectric constant of [Formula: see text] was studied at different temperatures, i.e. at 425, 450 and 475 K, in the frequency range of 1 kHz–5 MHz. It was found that the electrical conductivity decreases with increasing Cu[Formula: see text] ion content while it increases with the increase in temperature.


2019 ◽  
Vol 807 ◽  
pp. 50-56
Author(s):  
Yun Long Zhou ◽  
Zhi Biao Hu ◽  
Li Mei Wu ◽  
Jiao Hao Wu

Using hydrated manganese sulfate and general type graphene (GR) as raw materials, Mn3O4/GR composite has been successfully prepared by the liquid phase chemical co-precipitation method at room temperature. X-ray diffraction (XRD) was used to investigate the phase structure of Mn3O4powder and Mn3O4/GR composite; The electrochemical performances of the samples were elucidated by cyclic voltammetry and galvanostatic charge-discharge test in 0.5 mol/L Na2SO4electrolyte. The results show that the Mn3O4/GR composite possesses graphene phase and good reversibility; the composite also displays a specific capacitance of 318.8 F/g at a current density of 1 A/g.


e-Polymers ◽  
2006 ◽  
Vol 6 (1) ◽  
Author(s):  
J. L. Feng ◽  
C. Y. Yue ◽  
K. S. Chian

AbstractThis project aims to develop and characterize a series of bismaleimide (BMI) polymers based on maleic anhydride and aliphatic-ether diamines. The effects of varying the chain length of aliphatic-ether diamines on the resultant bismaleimide systems were evaluated so that their suitability for microelectronics applications could be evaluated. The synthetic reaction and properties of the bismaleimide materials were investigated using Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), Thermo- Gravimetric Analysis (TGA), Dielectric Thermal Analysis (DEA) and rheometry. Results showed that thermal, dielectric and rheological properties were all affected by the main chain length of BMI. The magnitude of the dielectric constant at 100 kHz increases with the increasing chain length. The curing peak temperature, curing heat and degradation temperature of BMI, all decrease with the increasing chain length.


2015 ◽  
Vol 05 (03) ◽  
pp. 1550018 ◽  
Author(s):  
P. Thomas ◽  
B. S. Dakshayini ◽  
H. S. Kushwaha ◽  
Rahul Vaish

Composites of poly(methyl methacrylate) (PMMA) and [Formula: see text] (STMO) were fabricated via melt mixing followed by hot pressing technique. These were characterized using X-ray diffraction (XRD), thermo gravimetric analysis (TGA), differential scanning calorimetry (DSC), thermo mechanical analysis (TMA) and impedance analyser for their structural, thermal and dielectric properties. The coefficient of thermal expansion (CTE) was measured between 40°C and 100°C for pure PMMA is 115.2 ppm/°C, which was decreased to 78.58 ppm/°C when the STMO content was increased to 50 wt.% in PMMA. There was no difference in the glass transition ([Formula: see text]) temperature of the PMMA polymer and their composites. However, the FTIR analysis indicated possible interaction between the PMMA and STMO. The density and the hardness were increased as the STMO content increased in the PMMA matrix. Permittivity was found to be as high as 30.9 at 100 Hz for the PMMA+STMO-50 wt.% composites, indicating the possibility of using these materials for capacitor applications. The thermal stability of polymer was enhanced by incorporation of STMO fillers.


2019 ◽  
Vol 92 ◽  
pp. 11006 ◽  
Author(s):  
Domenico De Sarno ◽  
Enza Vitale ◽  
Dimitri Deneele ◽  
Marco Valerio Nicotera ◽  
Raffaele Papa ◽  
...  

One of the main problems encountered in civil engineering is the management of large amounts of excavated soil, especially when the mechanical properties of this soil are not suitable for its reuse as a construction material. However, the excavated soil could represent a resource if appropriately improved. A suitable solution is the addition of cement and foam to produce lightweight cemented soils (LWCS). In this paper, an insight into the influence of foam on chemo-mineralogical and microstructural features of soil-cement-water system is presented. Time dependent mineralogical and microstructural changes have been monitored by means of X-Ray Diffraction, Thermo-gravimetric analysis and Mercury Intrusion Porosimetry. The present study shows that addition of foam does not alter the chemo-physical evolution of the soil-cement-water system. Large voids are present in the samples as footprint of air bubbles upon mixing, thus increasing porosity. Macroscopic behaviour of treated samples has been investigated by direct shear and oedometric tests. Chemo-physical evolution induced by cement addition is the major responsible for mechanical improvement showed by treated samples. Porosity of samples induced by foam addition plays a key role in the mechanical response of LWCS, inducing a transition of stress-strain behaviour from brittle and dilative to ductile and contractive as a function of increasing foam content.


Sign in / Sign up

Export Citation Format

Share Document