OPTIMIZING PARAMETERS IN SYNTHESIS OF LiF NANOPOWDERS VIA SOL–GEL METHOD

NANO ◽  
2011 ◽  
Vol 06 (06) ◽  
pp. 575-581 ◽  
Author(s):  
FAEZEH NIKANJAM ◽  
RASOUL SARRAF-MAMOORY ◽  
NASTARAN RIAHI-NOORI
Keyword(s):  
Lithium Fluoride ◽  
Sol Gel ◽  
Decomposition Temperature ◽  
Organic Additive ◽  
Ion Concentration ◽  
Optimum Conditions ◽  
Gel Method ◽  
Sol Gel Method ◽  
Li Ion ◽  
Gel Processing

Lithium fluoride (LiF) nanopowders were prepared by trifluoroacetate-based sol–gel processing. In this work, lithium acetate dehydrate ( LiAc ⋅ 2H2O ) and trifluoroacetic acid (TFA) was used as lithium and fluorine sources. The thermal behavior of initial gel was examined using differential thermal analysis (DTA). Effects of solvent (glacial acetic acid, absolute ethanol, and ethylene glycol), Li+ concentration (0.5, 1, and 2 mol/l) and decomposition temperature (200, 250, and 300°C) on synthesis of LiF nanopowders by sol–gel method were investigated. The results of LPSA, FE-SEM, and XRD showed that the growth of particles and aggregation can be controlled by changing above parameters. However, it is indicated that optimum conditions are; solvent as ethanol, Li ion concentration (0.5 mol/l), and decomposition temperature (300°C), respectively. Also, the addition of oleic acid as an organic additive made the final LiF particles finer and about 70–90 nm.

Iron-Zircon Pigments Prepared by Non-Hydrolytic Sol-Gel Method at Low Temperature

2011 ◽  
Vol 412 ◽  
pp. 223-226 ◽  
Author(s):  
Wei Hui Jiang ◽  
Yan Hui Yang ◽  
Qing Xia Zhu ◽  
Jian Min Liu
Keyword(s):  
Crystal Structure ◽  
Low Temperature ◽  
Ferric Chloride ◽  
Lithium Fluoride ◽  
Sol Gel ◽  
Zircon Crystal ◽  
Molar Ratio ◽  
Gel Method ◽  
Sol Gel Method ◽  
Anhydrous Ferric Chloride

ron-zircon pigment has been synthesized by non-hydrolytic sol-gel method using zirconium chloride and tetraethoxysilane as precursors, anhydrous ferric chloride as colorant, lithium fluoride as mineralizer and anhydrous ethanol as solvent. Iron-zircon pigment has been characterized by means of DTA-TG, XRD, Colorimeter and TEM. The results show that only a small fraction of iron is incorporated in the zircon crystal structure while the remaining iron cations are trapped within the zircon matrix. The iron-zircon with the red value (a*) of 20.64 can be synthesized at 700°C with the optimum Fe/Zr molar ratio of 0.2.

Synthesis of LiNi0.5Mn1.5O4 Nano- and Micropolyhedra via Sol–Gel Method and Their Application for Li-Ion Batteries

2013 ◽  
Vol 2 (1) ◽  
pp. 68-72 ◽  
Author(s):  
Wei Liu ◽  
Jun Liu ◽  
Yanling Wan ◽  
Shaomin Ji ◽  
Yichun Zhou
Keyword(s):  
Sol Gel ◽  
Li Ion Batteries ◽  
Gel Method ◽  
Sol Gel Method ◽  
Li Ion

FACILE SOL–GEL SYNTHESIS OF Li[Li0.2Mn0.56Ni0.16Co0.08]O2 AS IMPROVED CATHODE MATERIAL FOR LITHIUM-ION BATTERIES

2013 ◽  
Vol 01 (04) ◽  
pp. 1340015
Author(s):  
WENJUAN HAO ◽  
HAN CHEN ◽  
YANHONG WANG ◽  
HANHUI ZHAN ◽  
QIANGQIANG TAN ◽  
...  
Keyword(s):  
Cathode Materials ◽  
Sol Gel ◽  
Specific Capacity ◽  
Lithium Ion ◽  
Electrochemical Performances ◽  
Acetate Tetrahydrate ◽  
Li Ion Batteries ◽  
Gel Method ◽  
Sol Gel Method ◽  
Li Ion

Li [ Li 0.2 Mn 0.56 Ni 0.16 Co 0.08] O 2 cathode materials for Li -ion batteries were synthesized by a facile sol–gel method followed by calcination at various temperatures (700°C, 800°C and 900°C). Lithium acetate dihydrate, manganese (II) acetate tetrahydrate, nickel (II) acetate tetrahydrate and cobalt (II) acetate tetrahydrate are employed as the metal precursors, and citric acid monohydrate as the chelating agent. For the obtained Li [ Li 0.2 Mn 0.56 Ni 0.16 Co 0.08] O 2 materials, the metal components existed in the form of Mn 4+, Ni 2+ and Co 3+, and their molar ratio was in good agreement with 0.56 : 0.16 : 0.08. The calcination temperature played an important role in the particle size, crystallinity and further electrochemical properties of the cathode materials. The Li [ Li 0.2 Mn 0.56 Ni 0.16 Co 0.08] O 2 material calcined at 800°C for 6 h showed the best electrochemical performances. Its discharge specific capacities cycled at 0.1 C, 0.5 C, 1 C and 2 C rates were 266.0 mAh g−1, 243.1 mAh g−1, 218.2 mAh g−1 and 192.9 mAh g−1, respectively. When recovered to 0.1 C rate, the discharge specific capacity was 260.2 mAh g−1 and the capacity loss is only 2.2%. This work demonstrates that the sol–gel method is a facile route to prepare high performance Li [ Li 0.2 Mn 0.56 Ni 0.16 Co 0.08] O 2 cathode materials for Li -ion batteries.

Li+ ion diffusion in LiMn2O4 thin film prepared by PVP sol–gel method

2006 ◽  
Vol 157 (1) ◽  
pp. 471-476 ◽  
Author(s):  
Young Ho Rho ◽  
Kaoru Dokko ◽  
Kiyoshi Kanamura
Keyword(s):  
Thin Film ◽  
Sol Gel ◽  
Ion Diffusion ◽  
Gel Method ◽  
Sol Gel Method ◽  
Li Ion

Sol-gel processing of varistor powders

1992 ◽  
Vol 7 (3) ◽  
pp. 546-548 ◽  
Author(s):  
Gert Hohenberger ◽  
Gerhard Tomandl
Keyword(s):  
Grain Boundaries ◽  
Mixed Oxide ◽  
Sol Gel ◽  
Homogeneous Distribution ◽  
Electrical Behavior ◽  
Gel Method ◽  
Sol Gel Method ◽  
Zno Varistor ◽  
Gel Processing ◽  
Source Materials

A new sol-gel method for the preparation of ZnO varistor powders, using inexpensive source materials such as acetates and nitrates, is described. It yields powders with a more homogeneous distribution of dopants compared to the commercially used mixed oxide technique. Varistor ceramics made from sol-gel powders can be sintered at lower temperatures and show improved electrical behavior. This is a consequence of formation of more varistor-active grain boundaries within the ceramics.

scholarly journals Li Conductivity of Nanocrystalline Li4Ti5O12 Prepared by a Sol-Gel Method and High-Energy Ball Milling

2009 ◽  
Vol 289-292 ◽  
pp. 565-570 ◽  
Author(s):  
W. Iwaniak ◽  
J. Fritzsche ◽  
M. Zukalová ◽  
R. Winter ◽  
Martin Wilkening ◽  
...  
Keyword(s):  
Particle Size ◽  
Crystallite Size ◽  
Sol Gel ◽  
High Energy ◽  
Average Particle ◽  
Li Ion Batteries ◽  
Gel Method ◽  
Sol Gel Method ◽  
Li Ion ◽  
20 Nm

Spinel-type structured Li4+xTi5O12 (0 6 x 6 3 ) is actually one of the most promising anode materials for Li ion batteries. In its nanostructured form it is already used in some commercially available Li ion batteries. As was recently shown by our group (Wilkening et al., Phys. Chem. Chem. Phys. 9 (2007) 1239), Li diffusivity in microcrystalline Li4+xTi5O12 with x = 0 is rather slow. In the present contribution the Li conductivity in nanocrystalline samples of the electronic insulator Li4Ti5O12 prepared by different routes is investigated using impedance spectroscopy. The mean crystallite size of the samples is about 20 nm. The ionic conductivity of nanocrystalline Li4Ti5O12 obtained by mechanical treatment is higher by about two orders of magnitude compared to that found for a material which was prepared following a sol-gel method. The latter resembles the behaviour of the microcrystalline sample with an average particle size in the μm range rather than that of a nanocrystalline ball milled one with a mean crystallite size of about than 20 nm. The larger conductivity of the ball milled sample is ascribed to a much higher defect density generated when the particle size is reduced mechanically.

Preparation and magnetic performance of Co 0.8 Fe 2.2 O 4 by a sol–gel method using cathode materials of spent Li-ion batteries

2016 ◽  
Vol 42 (1) ◽  
pp. 1897-1902 ◽  
Author(s):  
Li Yang ◽  
Guoxi Xi ◽  
Tianjun Lou ◽  
Xinsheng Wang ◽  
Jingjing Wang ◽  
...  
Keyword(s):  
Cathode Materials ◽  
Sol Gel ◽  
Li Ion Batteries ◽  
Gel Method ◽  
Sol Gel Method ◽  
Magnetic Performance ◽  
Li Ion
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