Synthesis of electroactive mesoporous gold–organosilica nanocomposite materials via a sol–gel process with non-surfactant templates and the electroanalysis of ascorbic acid

2013 ◽  
Vol 1 (38) ◽  
pp. 4983 ◽  
Author(s):  
Chang-Jian Weng ◽  
Po-Hsuan Hsu ◽  
Sheng-Chieh Hsu ◽  
Chi-Hao Chang ◽  
Wei-I. Hung ◽  
...  
Keyword(s):  
Ascorbic Acid ◽  
Sol Gel ◽  
Nanocomposite Materials ◽  
Sol Gel Process ◽  
Surfactant Templates

Preparation of Titanium Oxide and Metal Titanates as Powders, Thin Films, and Microspheres by Novel Inorganic Sol-Gel Process

2005 ◽  
Vol 900 ◽  
Author(s):  
A. Deptuła ◽  
Kenneth C Goretta ◽  
Tadeusz Olczak ◽  
Wieslawa Lada ◽  
Andrzej G. Chmielewski ◽  
...  
Keyword(s):  
Thin Films ◽  
Ascorbic Acid ◽  
Nitric Acid ◽  
Titanium Oxide ◽  
Sol Gel ◽  
Solid State Reactions ◽  
X Ray Diffraction ◽  
Metal Hydroxides ◽  
X Ray ◽  
Sol Gel Process

ABSTRACTTitanium oxide and titanates based on Ba, Sr and Ca were prepared from commercial solutions of TiCl4 and HNO3. The main preparation steps for the sols consisted of elimination of chloride anions by distillation with nitric acid and addition of metal hydroxides for the titanates. Resulting sols were gelled and used to (1) prepare irregularly shaped powders by evaporation; (2) produce by a dipping technique thin films on glass, Ag, or Ti substrates; and (3) produce spherical powders (diameters <100 μm) by solvent extraction. Results of thermal and X-ray-diffraction analyses indicated that the temperatures required to form the various compounds were lower than those necessary to form the compounds by conventional solid-state reactions and comparable to those required with use of organometallic based sol-gel methods. Temperatures of formation could be further reduced by addition of ascorbic acid to the sols.

Polyacrylate/silica nanocomposite materials prepared by sol–gel process

2007 ◽  
Vol 43 (10) ◽  
pp. 4169-4177 ◽  
Author(s):  
Jian-Zhong Ma ◽  
Jing Hu ◽  
Zhi-Jie Zhang
Keyword(s):  
Sol Gel ◽  
Nanocomposite Materials ◽  
Sol Gel Process ◽  
Silica Nanocomposite

Synthesis and Electrochemical characterization of LiNi1-yCoyO2 powders obtained by complex sol-gel process

1999 ◽  
Vol 575 ◽  
Author(s):  
F. Croce ◽  
A. D'Epifanio ◽  
A. Deptula ◽  
W. Lada ◽  
A. Ciancia ◽  
...  
Keyword(s):  
Ascorbic Acid ◽  
Solid Solutions ◽  
Electrode Materials ◽  
Thermal Transformation ◽  
Sol Gel ◽  
Lithium Ion ◽  
Cell Voltage ◽  
High Energy ◽  
High Energy Density ◽  
Sol Gel Process

ABSTRACTThe layered oxides, among the wide family of intercalation compounds, have received considerable attention as positive electrode materials in high-energy density lithium and lithium ion batteries. Within this frame LiNiO2 and LiCoO2 oxides and their solid solutions have been extensively studied as they (and the LiMn2O4 spinels) are the only known materials able to intercalate reversibly lithium at high cell voltage (3.5-4 V). Recently, solid solutions such as LiNi1-xCoxO2 have attracted the attention as alternative cathodes to the state of art LiCoO2 in commercial rechargeable Li-ion batteries. Here we have used the Complex Sol-Gel Process (CSGP) to prepare LiNi1-xCoxO2 (x= 0, 0.25, 0.5, 0.75, 1). Starting sols were prepared from Li+-(1-x)Ni2+-xCo2+ acetate aqueous solution in two different routes. According to route-A aqueous ammonia was added to a starting solution containing 0.2M ascorbic acid (ASC) on 1 M total Me. According to route B the starting acetate solutions were first alkalized by ammonia and then the ascorbic acid was added. Regular sols were concentrated to 1/3 of their initial volume and dried slowly up to 170°C. Thermal transformation of the gels to solids was studied by XRD and IR. The electrochemical properties of the compound LiNi0.75Co0.25O2 prepared by the Route-A were evaluated and reported.

scholarly journals Carbonization of solid uranyl-ascorbate gel as an indirect step of uranium carbide synthesis

Nukleonika ◽  
2015 ◽  
Vol 60 (4) ◽  
pp. 921-925 ◽  
Author(s):  
Marcin Brykala ◽  
Marcin Rogowski ◽  
Tadeusz Olczak
Keyword(s):  
Ascorbic Acid ◽  
Sol Gel ◽  
Nitrogen Atmosphere ◽  
Complexing Agent ◽  
X Ray Diffraction ◽  
Crucial Step ◽  
X Ray ◽  
Uranium Carbide ◽  
Vacuum Atmosphere ◽  
Sol Gel Process

Abstract The studies of the synthesis of uranium carbide from uranyl-ascorbate gels using the complex sol-gel process (CSGP) have been carried out. The synthesis of uranyl-ascorbate mixture as liquid sol from uranium trioxide and ascorbic acid and solid gel by extraction of water from sol were carefully examined. Ascorbic acid was used as a complexing agent in complex sol-gel process and as a carbon source. The crucial step to obtain final uranium carbides from the aforementioned substrates is the carbonization process. The thermal behavior of ascorbic acid and uranyl-ascorbate gels in a nitrogen atmosphere in the temperature range of 25-900°C were investigated using TG-DTG. Furthermore, the products of the carbonization of uranyl-ascorbate gels in nitrogen, argon and vacuum atmosphere were identified by X-ray diffraction. TG-DTG was used also as a method for determining of carbon residues in the samples.

Sol-gel process for preparation of YBa2Cu4O8 from acidic acetates/ammonia/ascorbic acid systems

1997 ◽  
Vol 32 (3) ◽  
pp. 319-325 ◽  
Author(s):  
A. Deptula ◽  
W. Lada ◽  
T. Olczak ◽  
K.C. Goretta ◽  
A. Di Bartolomeo ◽  
...  
Keyword(s):  
Ascorbic Acid ◽  
Sol Gel ◽  
Sol Gel Process

On-Line Monolithic Enzyme Reactor Fabricated by Sol-Gel Process for Elimination of Ascorbic Acid While Monitoring Dopamine

2005 ◽  
Vol 17 (3) ◽  
pp. 231-238 ◽  
Author(s):  
Zilin Chen ◽  
Katsuyoshi Hayashi ◽  
Yuzuru Iwasaki ◽  
Ryoji Kurita ◽  
Osamu Niwa ◽  
...  
Keyword(s):  
Ascorbic Acid ◽  
Sol Gel ◽  
Enzyme Reactor ◽  
Sol Gel Process ◽  
On Line

Preparation Of Pt/WO3 Powders and Thin Coatings on Carbon Black and Metal Supports by The Complex Sol-Gel Process (CSGP)

1997 ◽  
Vol 496 ◽  
Author(s):  
A. Deptula ◽  
W. Lada ◽  
T. Olczak ◽  
B. Sartowska ◽  
A. Ciancia ◽  
...  
Keyword(s):  
Ascorbic Acid ◽  
Thermal Treatment ◽  
Carbon Black ◽  
Sol Gel ◽  
Molar Ratio ◽  
Thin Coatings ◽  
Ascorbic Acid Solution ◽  
Sol Gel Process ◽  
Immersion Technique ◽  
Metal Supports

ABSTRACTIn this work the CSGP was applied for preparation of Pt-WOx and its coatings on carbon black, silver and titan substrates. Saturated tungsten sol (0.15M) was prepared by dissolving (NH4)4W5O17 2.5 H2O in ascorbic acid solution. To this solution H2PtCl6 was added to obtain the molar ratio Pt:W=l. After evaporation and heating at 700°C for 2h homogeneous yellow-green powders were obtained. Another part of this solution was diluted with ethanol and after ultrasonic mixing used for preparation of coatings on Ag and Ti substrates by the immersion technique. Gel layers were dried at 200°C for 20h and then calcined at 700°C for 2h. The resulting white colored layers (thickness 10–65μm) were very adherent. Ascorbate aqueous tungsten-platinum sol diluted to 0.03 or 0.06 M ΣMe was used for preparation of Pt-W (10 and 20 %) catalyst by impregnation of carbon black Vulcan XC-72, followed by thermal treatment in air, argon and hydrogen atmospheres.

Novel Sol-Gel Synthesis of LiMn2O4 and LiNixCo1-xO2 Powders

2010 ◽  
Vol 63 ◽  
pp. 14-23 ◽  
Author(s):  
Andrzej Deptula ◽  
Wiesława Łada ◽  
Tadeusz Olczak ◽  
Danuta Wawszczak ◽  
Marcin Brykala ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Ascorbic Acid ◽  
Total Pressure ◽  
Sol Gel ◽  
Heating Rates ◽  
Reduced Pressure ◽  
X Ray ◽  
Sol Gel Process ◽  
Phase Pure ◽  
Sol Gel Synthesis

A modified complex sol-gel process was developed to synthesize LiMn2O4 and LiNixCo1-xO2 powders. Sols were prepared from 1.5 M of Mn2+ or 1 M of xNi2+ and (1-x)Co2+ acetates plus ascorbic acid aqueous solutions by alkalizing them with LiOH and NH4OH. Ascorbic acid was added to prevent precipitation in the precursor solutions. When the sols were concentrated to one-third of their initial volume under reduced pressure and then gelled by drying for 10 days, heat treatment to ≥700 °C was accompanied by foaming, violent self-ignition, and formation of carbonates in the Ni-containing species. Significant improvements to the process and resulting powders were gained by modifying the gelation step. When gelation and drying were carried out under reduced total pressure, subsequent heating produced self-ignition, but no foaming, for all heating rates. The resulting products were determined to be nearly phase pure and carbonate free by thermogravimetric, differential thermal, X-ray, and infrared spectroscopy methods.

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