Effect of Carbon Sources and Synthesis Conditions on the LiFePo4/C Cathode Properties

Abstract The sol-gel synthesis and precipitation from dimethyl sulfoxide (DMSO)-water mixture were used to obtain LiFePO4. Sucrose (sucr), citric acid (CA), phthalic acid (phth), polyvinyl alcohol (PVA), polyvinylpyrrolidone (PVP), polyvinylidene fluoride (PVDF), polyethylene glycol (PEG), polyacrylic acid (PAA) were investigated as carbon precursors. Increasing of the annealing temperature from 600 °» to 800 °» leads to a certain perfection of graphite structure with simultaneous particle size growth. Higher capacities were observed for the materials synthesized at 600 °». The best results for the sol-gel synthesis were obtained when PVDF was used as a source of carbon coating due to the partial fluorination of LiFePO4 (discharge capacity of LiFePO4/ C-PVDF was ~160 and 70 mAh g-1 at 20 mA g-1 and 800 mA g-1 currents, respectively). For nanocrystalline LiFePO4 obtained by precipitation from DMSO-water mixture the best results were obtained when PEG was used as carbon source (discharge capacity LiFePO4/C-PEG was 158 and 77 mAh g-1 at 20 mA g-1 and 800 mA g-1, respectively).

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V2O3/C composite fabricated by carboxylic acid-assisted sol–gel synthesis as anode material for lithium-ion batteries

Journal of Sol-Gel Science and Technology ◽

10.1007/s10971-021-05523-z ◽

2021 ◽

Author(s):

G. S. Zakharova ◽

E. Thauer ◽

A. N. Enyashin ◽

L. F. Deeg ◽

Q. Zhu ◽

...

Keyword(s):

Electrochemical Performance ◽

Lithium Ion Batteries ◽

Sol Gel ◽

Carbon Sources ◽

Lithium Ion ◽

X Ray Diffraction ◽

Electron Microscopies ◽

Transmission Electron ◽

Battery Electrode ◽

Sol Gel Synthesis

AbstractThe potential battery electrode material V2O3/C has been prepared using a sol–gel thermolysis technique, employing vanadyl hydroxide as precursor and different organic acids as both chelating agents and carbon sources. Composition and morphology of resultant materials were characterized by X-ray diffraction, Raman spectroscopy, scanning and transmission electron microscopies, physical sorption, and elemental analysis. Stability and electronic properties of model composites with chemically and physically integrated carbon were studied by means of quantum-chemical calculations. All fabricated composites are hierarchically structured and consist of carbon-covered microparticles assembled of polyhedral V2O3 nanograins with intrusions of amorphous carbon at the grain boundaries. Such V2O3/C phase separation is thermodynamically favored while formation of vanadium (oxy)carbides or heavily doped V2O3 is highly unlikely. When used as anode for lithium-ion batteries, the nanocomposite V2O3/C fabricated with citric acid exhibits superior electrochemical performance with an excellent cycle stability and a specific charge capacity of 335 mAh g−1 in cycle 95 at 100 mA g−1. We also find that the used carbon source has only minor effects on the materials’ electrochemical performance.

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NANOSTRUCTURED SnO2/C COMPOSITE ANODES IN LITHIUM-ION BATTERIES

International Journal of Nanoscience ◽

10.1142/s0219581x03001322 ◽

2003 ◽

Vol 02 (04n05) ◽

pp. 299-306 ◽

Cited By ~ 1

Author(s):

CHIEN-TE HSIEH ◽

JIN-MING CHEN ◽

HSIU-WEN HUANG

Keyword(s):

Lithium Ion Batteries ◽

Discharge Capacity ◽

Coulombic Efficiency ◽

Sol Gel ◽

Lithium Ion ◽

Surface Characteristics ◽

Carbon Surface ◽

Cyclic Voltammograms ◽

Composite Anodes ◽

Sol Gel Synthesis

Nanostructured SnO 2/ C composites used as anode materials were prepared by sol–gel synthesis to explore electrochemical properties in lithium-ion batteries. Surface characteristics of the SnO 2/ C nanocomposite were analyzed by X-ray diffraction (XRD) and transmission electron microscopy (TEM). It was found that nanocrystalline SnO 2/ C with a grain size of 20–50 nm was uniformly dispersed on the carbon surface. After nanocrytalline SnO 2 coated onto carbon, the discharge capacity showed an increase up to 23%, i.e., from 300 to 370 mAh/g at a current density of 0.6 mA/cm2. The nanocomposite anode can achieve a fairly stable discharge capacity and excellent Coulombic efficiency (>99.5%) over 50 cycles. Cyclic voltammograms indicated that the improvements on capacity and cycleability were due to reversible alloying of nanosized Sn and Li on carbon surface.

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Effect of sol–gel synthesis conditions on the physical properties of silica hydrogels

Mendeleev Communications ◽

10.1016/j.mencom.2020.11.041 ◽

2020 ◽

Vol 30 (6) ◽

pp. 812-814

Author(s):

Ekaterina S. Dolinina ◽

Anton S. Kraev ◽

Elena V. Parfenyuk

Keyword(s):

Physical Properties ◽

Sol Gel ◽

Synthesis Conditions ◽

Silica Hydrogels ◽

Sol Gel Synthesis

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Correction: Role of annealing temperature on the sol–gel synthesis of VO2 nanowires with in situ characterization of their metal–insulator transition

RSC Advances ◽

10.1039/c8ra90075b ◽

2018 ◽

Vol 8 (56) ◽

pp. 31984-31984

Author(s):

Y.-R. Jo ◽

S.-H. Myeong ◽

B.-J. Kim

Keyword(s):

Annealing Temperature ◽

Sol Gel ◽

Insulator Transition ◽

In Situ Characterization ◽

Metal Insulator Transition ◽

Metal Insulator ◽

Sol Gel Synthesis

Correction for ‘Role of annealing temperature on the sol–gel synthesis of VO2 nanowires with in situ characterization of their metal–insulator transition’ by Y.-R. Jo et al., RSC Adv., 2018, 8, 5158–5165.

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Effect of the Sol-Gel Synthesis Parameters on the Incorporation of an Anti-inflammatory Drug in a Ceramic Material

MRS Proceedings ◽

10.1557/proc-1007-s08-02 ◽

2007 ◽

Vol 1007 ◽

Author(s):

Aracely Hernandez ◽

Patricia Esquivel-Ferriño ◽

Idalia Gomez ◽

Lucia Cantu

Keyword(s):

Ceramic Material ◽

Sol Gel ◽

Nitrogen Adsorption ◽

Molar Ratio ◽

Inflammatory Drug ◽

Synthesis Conditions ◽

Synthesis Parameters ◽

Anti Inflammatory ◽

Drug Incorporation ◽

Sol Gel Synthesis

ABSTRACTIn the present work, sol-gel method was used to incorporate in a ceramic material a non steroidal anti-inflammatory drug (piroxicam) as model drug. The incorporation of the drug in the SiO2 network was carried out at different sol-gel synthesis parameters, such as pH (3 and 5) and the alkoxide/water ratio (1:6 and 1:8). The biomaterial obtained was analyzed by thermal analysis TGA-DTA, infrared spectroscopy (FTIR), Scanning Electronic Microscopy (SEM) and X-ray diffraction (XRD); specific surface area and porosity were analyzed from nitrogen adsorption isotherm. Better drug incorporation into the material was achieved at the synthesis conditions of pH 5 and 1:6 alkoxide/water molar ratio.

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Synthesis of Silica Nanostructures and Optimization of their Size and Morphology by Use of Changing in Synthesis Conditions

E-Journal of Chemistry ◽

10.1155/2012/109765 ◽

2012 ◽

Vol 9 (2) ◽

pp. 659-668 ◽

Cited By ~ 4

Author(s):

A. Elsagh

Keyword(s):

Drug Delivery Systems ◽

Sol Gel ◽

Molar Ratio ◽

Synthesis Conditions ◽

Acid Type ◽

Silica Nanostructures ◽

Size And Morphology ◽

Sol Gel Synthesis ◽

Optimized Conditions ◽

Cracking Products

The aim of the present research was optimization of practical conditions of the sol-gel synthesis. In so doing, silica particles were synthesized using sol-gel method and their size and morphology were investigated by use of SEM and TEM images. The effect of changing molar ratio of reactive including acids and silica pre-matter on the particles' morphology and size was studied. Also, acid type and silica pre-matter used in reaction was examined and the result product of the reaction were investigated in the presence of several acids and two types of silica pre-matter. The reaction time was studied as a very important factor in products' digestion phase which plays a significant role in determining particles’ size and rate of cracking products. Finally, in optimized conditions 50-80 nm diameter nanostructures were synthesized. These products can be used as drug delivery systems.

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Sol-Gel Synthesis and Structural Characterization of Nano-Thiamine Hydrochloride Structure

ISRN Nanotechnology ◽

10.1155/2013/815071 ◽

2013 ◽

Vol 2013 ◽

pp. 1-4 ◽

Cited By ~ 2

Author(s):

Salameh Azimi

Keyword(s):

Sol Gel ◽

Catalyst Support ◽

Morphological Observation ◽

Glassy Matrix ◽

Thiamine Hydrochloride ◽

Water Mixture ◽

X Ray Diffraction ◽

Silica Source ◽

Sol Gel Synthesis

The study presents the synthesis of nano-thiamine hydrochloride structure (NTH) using sol-gel method by hydrolysis of tetraethyl orthosilicate with ethanol and water mixture as silica source and nitric acid as catalyst support in which thiamine hydrochloride nanocrystals were dispersed in the silica glassy matrix. The synthesized nanocomposite was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and differential thermal analysis (DTA). The morphological observation of the SEM results reveals that the nano-thiamine hydrochloride composites are in the range of 5–15 nm in size.

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Facile Sol-gel Synthesis of Porous Silicas Using Poly(propylene)imine Dendrimers as Templates

Journal of Materials Research ◽

10.1557/jmr.2000.0266 ◽

2000 ◽

Vol 15 (8) ◽

pp. 1842-1848 ◽

Cited By ~ 14

Author(s):

Gustavo Larsen ◽

Edgar Lotero ◽

Manuel Marquez

Keyword(s):

Single Molecule ◽

Sol Gel ◽

Three Dimensional ◽

X Ray Diffraction ◽

Template Removal ◽

Synthesis Conditions ◽

Transmission Electron ◽

Argon Adsorption ◽

Poly Propylene ◽

Sol Gel Synthesis

Commercially available poly(propylene)imine (DAB-Am-32 and DAB-Am-64) dendrimers were used as single-molecule templates to tailor the porosity of silicas via a nonacidic sol-gel method. X-ray diffraction on both the as-prepared (oven-dried at 373 K) and the calcined (833 K) materials revealed that modest contraction took place on template removal and that the cavities created did not achieve three-dimensional ordering under the current synthesis conditions. Transmission electron microscopy of “Pt-stained” samples supported this picture. A modified Horvath–Kawazoe analysis of the argon adsorption isotherms indicated that DAB-Am-64 is a much more effective template than DAB-Am-32. Pyrolysis and oxidation protocols for template removal are also presented.

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Sol-gel synthesis, crystal structure and magnetic properties of nanocrystalline praseodymium orthoferrite

Kondensirovannye sredy i mezhfaznye granitsy = Condensed Matter and Interphases ◽

10.17308/kcmf.2021.23/3429 ◽

2021 ◽

Vol 23 (2) ◽

pp. 196-203

Author(s):

Xuan Vuong Bui ◽

Anh Tien Nguyen

Keyword(s):

Crystal Structure ◽

Magnetic Properties ◽

Single Phase ◽

Crystal Size ◽

Annealing Temperature ◽

Sol Gel ◽

Gel Method ◽

Lattice Volume ◽

Sol Gel Synthesis ◽

Paramagnetic Properties

In this work, nano-sized crystalline praseodymium orthoferrite was successfully synthesized via sol-gel method using water – methanol co-solvent. Single-phase PrFeO3 nanoparticles were formed after annealing the precursors at 650, 750, 850, and 950 °C during 60 min. The crystal size, lattice volume and coercivity (Hc) of nanocrystalline PrFeO3 increase with the annealing temperature. The obtained praseodymium orthoferrite exhibited paramagnetic properties with Hc = 28 – 34 Oe

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Peculiarities of sol-gel synthesis of co-modified by nitrogen and metal ions (Zn2+, Zr4+, Pt2+) semiconductive TiO2 films

Reports of the National Academy of Sciences of Ukraine ◽

10.15407/dopovidi2020.12.067 ◽

2020 ◽

pp. 67-74

Author(s):

О.P. Linnik ◽

◽

N.P. Smirnova ◽

A.М. Eremenko ◽

◽

...

Keyword(s):

Metal Ions ◽

Sol Gel ◽

Complex Compounds ◽

Chemical Compositions ◽

Reaction Products ◽

Synthesis Conditions ◽

No Formation ◽

Titania Films ◽

Sol Gel Synthesis ◽

Urea Decomposition

According to the XPS investigation of titania films co-modified by nitro gen and metal ions obtained via sol-gel method, the formation of common bonds between elements occurs due to the presence of metal ions. The mechanism of urea thermolysis is changed as a result of the ability of metal ions to form the complex compounds with urea molecules under the reported synthesis conditions that, in turn, depends on the nature of metal ions, leading to the different chemical compositions of materials’ surface. The XPS data show that nitrogen atoms are surrounded by nonmetal ones on the surface of the films modi fied by Zn2+ or Zr4+ ions. It is suggested that no formation of the complexes between Ті, Zn, or Zr atoms with urea occurs due to its protonation through an oxygen atom leading to the formation of O,N-containing reaction products. In the case of Pt2+ doping, the substitutional nitrogen incorporation in the titania lattice, as well as the formation of N-containing fragments, have been detected. The chemical nature of Pt ions allows them to interact with urea molecules through an N atom of the amino group. As a result, the transformation of urea molecules in the complexes occurs at higher temperatures concurrently with the titania crystallization that is recognized as a catalyst for the intermediates of the urea decomposition leading to the formation of common bonds between N and Ti atoms.

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