Evaluation of effect of synthesis parameters on the morphology of nano-structures of magnesium oxide coated with carbon

2021 ◽  
Vol 112 (10) ◽  
pp. 817-825
Author(s):  
Glaucea Warmeling Duarte ◽  
Gustavo Lopes Colpani ◽  
Luciano Luiz Silva ◽  
Cíntia Soares ◽  
Márcio Antônio Fiori ◽  
...  
Keyword(s):  
Magnesium Oxide ◽  
Carbon Concentration ◽  
Sol Gel ◽  
Synthesis Temperature ◽  
Magnesium Nitrate ◽  
Molar Ratio ◽  
Small Surface ◽  
Synthesis Parameters ◽  
One Step ◽  
Synthesis Procedure

Abstract In this study, the influence of the synthesis parameters on the microstructural properties of nanoparticles of magnesium oxide coated with carbon was investigated. The nanostructures were produced in a one-step synthesis procedure, following a sol-gel method, and the effects of the molar ratio between magnesium nitrate and glucose, the temperature and the dripping time on the morphology of the nanostructures formed were analyzed. The results indicate that an increase in carbon concentration, synthesis temperature around 60 °C and 4 h of dripping time favor the formation of small agglomerates of nanoparticles with greater carbon coating homogeneity. In general, high synthesis temperatures favor the kinetic aspects of crystallization and produce nanostructures with a larger crystallite size. On the other hand, altering the dripping time was not efficient in changing the morphology of the nanostructures obtained. In addition, increasing the carbon concentration favors the formation of structures with small surface area and pore volume.

Study on Preparation and Hydrophobicity of MTES Derived Silica Sol and Gel

2012 ◽  
Vol 535-537 ◽  
pp. 2563-2566 ◽  
Author(s):  
Yu Ma ◽  
Hye Ryeon Lee ◽  
Toshinori Tsuru
Keyword(s):  
Reaction Rate ◽  
Sol Gel ◽  
Phase Segregation ◽  
Silica Sol ◽  
Molar Ratio ◽  
Modified Silica ◽  
Sol Gel Process ◽  
One Step ◽  
Inorganic Precursors

The synthesis of hydrophobic sol by one-step sol-gel process ammonia catalyzed was investigated. The water molar ratio and catalyst molar ratio were discussed to prevent phase segregation during the hydrolysis and co-condensation of the organic and inorganic precursors. The reactant system with water molar ratio 70 could make the reaction rate of MTES slightly less than that of TEOS, so that the hydrolysis - condensation – gelling reaction with MTES and TEOS as co-precursors could be synchronously. With the increase of the MTES/TEOS molar ratio, the reaction rate of the silica sol preparation decreased, the hydrophobicity of the sol and gel increased as the molar ratio MTES/TEOS change from 0.5~4. But the hydrophobicity of the methyl-modified silica sol and gel prepared with pure MTES in the sol-gel process were slightly lower than that of the methyl-modified silica sol and gel prepared with MTES and TEOS as co-precursors.

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

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.

Synthesis and characterization of magnesium Oxide nanoparticles by sol-gel method

2020 ◽  
Vol 3 (3) ◽  
Author(s):  
Jegadeeswari A ◽  
Nivetha S
Keyword(s):  
Magnesium Oxide ◽  
Sol Gel ◽  
Morphological Characterization ◽  
Magnesium Nitrate ◽  
Oxide Nanoparticles ◽  
Mgo Nanoparticles ◽  
Gel Method ◽  
Sol Gel Method ◽  
Magnesium Oxide Nanoparticles

Magnesium oxide was hygroscopic solid mineral that occurs naturally as periclase.Magnesium oxide had high thermal conductivity; it gets heated when the electricity was passed through it. Magnesia crucible had a stability of 2400°C in air, 1700°C in reducing atmosphere. Magnesium oxide nanoparticles were obtained from the mixture of magnesium nitrate as precursor and sodium hydroxide as precipitating agent by sol-gel method. Finally,the resultant white crystalline powder of MgO was annealed at various temperatures of 80°C, 135°C and 180°C. The analytical studies (XRD, SEM FTIR, EDAX) reveals the morphological characterization of MgO nanoparticles. The Scanning Electron Microscopy (SEM) indicates the structures of MgO nanoparticles. The crystal size of MgO nanoparticles was obtained by X-Ray Diffraction (XRD). The optical properties of the sample were obtained by UV- Visible spectroscopy. Fourier Transform infrared spectroscopy indicates powdered composition of the sample. EDAX indicates elementary composition of the MgO nanoparticles.

One-step Solvothermal Synthesis and Characterization of BaTiO3 Nanoparticles

2005 ◽  
Vol 878 ◽  
Author(s):  
Helen Reveron ◽  
Cyril Aymonier ◽  
Anne Loppinet-Serani ◽  
Mario Maglione ◽  
Catherine Elissalde ◽  
...  
Keyword(s):  
Solvothermal Synthesis ◽  
Flow Reactor ◽  
Molar Ratio ◽  
Continuous Flow Reactor ◽  
Synthesis Parameters ◽  
Powder Characteristics ◽  
One Step ◽  
Reactor Temperature ◽  
Batio3 Nanoparticles

AbstractUsing a continuous-flow reactor, barium titanate (BaTiO3) nanoparticles have been successfully synthesized at temperatures ranging from 150 to 380°C and 16 MPa. Ba-Ti alkoxide solutions were used as precursors and water as reagent. The influence of synthesis parameters on the powder characteristics was investigated. Results showed that the purity, crystallinity and stoichiometry of the as-synthesized BaTiO3 powder depend mainly on the reactor temperature, quantity of water injected into the reactor and the Ba:Ti molar ratio of alkoxide solutions.

Synthesis of Magnesium Oxide Nanoparticles by Sol-Gel Process

2007 ◽  
Vol 558-559 ◽  
pp. 983-986 ◽  
Author(s):  
Rizwan Wahab ◽  
S.G. Ansari ◽  
M.A. Dar ◽  
Young Soon Kim ◽  
Hyung Shik Shin
Keyword(s):  
Magnesium Oxide ◽  
Sol Gel ◽  
Thermo Gravimetric Analysis ◽  
Magnesium Nitrate ◽  
Oxide Nanoparticles ◽  
Gravimetric Analysis ◽  
Magnesium Oxide Nanoparticles ◽  
Good Crystallinity ◽  
Sol Gel Process ◽  
Diffraction Patterns

Cubic shaped Magnesium oxide nanoparticles were successfully synthesized by sol-gel method using magnesium nitrate and sodium hydroxide at room temperature. Hydrated Magnesium oxide nanoparticles were annealed in air at 300 and 500°C. X-ray diffraction patterns indicate that the obtain nanoparticles are in good crystallinity, pure magnesium oxide periclase phase with (200) orientation. Morphological investigation by FESEM reveals that the typical sizes of the grown nanoparticles are in the range of 50-70nm. Powder composition was analyzed by the FTIR spectroscopy and the results confirms that the conversion of brucite phase magnesium hydroxide in to magnesium oxide periclase phase was achieved at 300°C.The Thermo-gravimetric analysis showed the phase transition of the synthesized magnesium oxide nanoparticles occurs at 280-300°C.

Synthesis and Microstructure of Al2O3-SiO2 Nanoparticles by a Sol-Gel Processing

2007 ◽  
Vol 124-126 ◽  
pp. 679-682 ◽  
Author(s):  
Sung Kang ◽  
Byung Ik Kim ◽  
Chang Yeoul Kim ◽  
Jong Kyu Lee ◽  
Dong Sik Bae
Keyword(s):  
Size Range ◽  
Condensation Reaction ◽  
Sol Gel ◽  
Sio2 Nanoparticles ◽  
Molar Ratio ◽  
Synthesis Parameters ◽  
Stirring Rate ◽  
Hydrolysis And Condensation ◽  
Average Size ◽  
Gel Processing

Al2O3-SiO2 nanoparticles have been synthesized by a sol-gel processing. Size and composition of the synthesized particles can be controlled by manipulating the relative rates of the hydrolysis and condensation reaction of precursor. The average size of synthesized Al2O3-SiO2 nanoparticles was about in the size range of 50~100nm. The effects of synthesis parameters, such as the molar ratio of water to precursor, the molar ratio of water to surfactant and stirring rate, are discussed.

scholarly journals Utilization of Lithium Incorporated Mesoporous Silica for Preventing Necrosis and Increase Apoptosis in Different Cancer Cells.

2018 ◽  
Author(s):  
Kamel A. Saleh ◽  
Sharah A. Aldulmani ◽  
Nasser Awwad ◽  
Mohammad Y. Alfaifi ◽  
Mohamed S. Hamdy ◽  
...  
Keyword(s):  
Mesoporous Silica ◽  
Cancer Cells ◽  
Active Sites ◽  
Drug Carrier ◽  
Sol Gel ◽  
Ic50 Value ◽  
One Step ◽  
Synthesis Procedure ◽  
New Compounds ◽  
Mcf 7

There are many molecules used as drug carrier. TUD-1 is a newly synthesized mesoporous silica (SM) molecule possess two important features; consists of mesoporous so it is very suitable to be drug carrier in addition to that it has the ability to induce apoptosis in cancer cells. However, the effect of TUD-1 appears to act as cell death inducer, regardless of whether it is necrosis or apoptosis. Unfortunately, recent studies indicate that a proportion of cells undergo necrosis rather than apoptosis, which limits the use of TUD-1 as a secure treatment. On the other hand, lithium considered as necrosis inhibitor element. Hence, current study based on the idea of production a new Li/TUD-1 by incorporated mesoporous silica (TUD-1 type) with lithium in order to produce a new compound that has the ability to activate apoptosis by mesoporous silica (TUD-1 type) and at the same time can inhibit the activity of necrosis by lithium. Herein, lithium was incorporated in TUD-1 mesoporous silica by using sol-gel technique in one step synthesis procedure. Moreover, lithium was incorporated in TUD-1 with different loading in order to form different active sites such as isolated lithium ions, nanoparticles of Li2O, and bulky crystals of Li2O. The ability of the new compounds to induce apoptosis and prevent necrosis was evaluated on three different types of cancer cell lines which are; liver HepG-2, Breast MCF-7 and colon HCT116. The obtained results show that Li/TUD-1has the ability to control necrosis and thus reduce the side effects of treatments containing silica in the case of lithium has been added to them, especially in chronic cases. This has been demonstrated by the significant increase in the IC50 value and cell viability comparing to control groups. Consequently, the idea is new, so it definitely needs more develop and test with materials that have more apoptotic impact than silica in order to induce apoptosis without induction of necrosis.

Efficient Micromixing for Continuous Biodiesel Production from Jatropha Oil

2018 ◽  
Vol 9 (1) ◽  
pp. 133-139
Author(s):  
Waleed S. Mohammed ◽  
Ahmed H. El-Shazly ◽  
Marwa F. Elkady ◽  
Masahiro Ohshima
Keyword(s):  
Methyl Esters ◽  
Continuous Process ◽  
Sol Gel ◽  
Average Diameter ◽  
Biodiesel Production ◽  
High Mass ◽  
Molar Ratio ◽  
Jatropha Oil ◽  
Energy Deficiency ◽  
Gel Preparation

Introduction: The utilization of biodiesel as an alternative fuel is turning out to be progressively famous these days because of worldwide energy deficiency. The enthusiasm for utilizing Jatropha as a non-edible oil feedstock is quickly developing. The performance of the base catalyzed methanolysis reaction could be improved by a continuous process through a microreactor in view of the high mass transfer coefficient of this technique. Materials & Methods: Nanozirconium tungstovanadate, which was synthetized using sol-gel preparation method, was utilized in a complementary step for biodiesel production process. The prepared material has an average diameter of 0.066 &µm. Results: First, the NaOH catalyzed methanolysis of Jatropha oil was investigated in a continuous microreactor, and the efficient mixing over different mixers and its impact on the biodiesel yield were studied under varied conditions. Second, the effect of adding the nanocatalyst as a second stage was investigated. Conclusion: The maximum percentage of produced methyl esters from Jatropha oil was 98.1% using a methanol/Jatropha oil molar ratio of 11 within 94 s using 1% NaOH at 60 &°C. The same maximum conversion ratio was recorded with the nanocatalyst via only 0.3% NaOH.

scholarly journals Eco-Friendly Colloidal Aqueous Sol-Gel Process for TiO2 Synthesis: The Peptization Method to Obtain Crystalline and Photoactive Materials at Low Temperature

Catalysts ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 768
Author(s):  
Julien G. Mahy ◽  
Louise Lejeune ◽  
Tommy Haynes ◽  
Stéphanie D. Lambert ◽  
Raphael Henrique Marques Marcilli ◽  
...  
Keyword(s):  
Organic Pollutant ◽  
Sol Gel ◽  
Synthesis Method ◽  
Specific Treatment ◽  
High Specific Surface Area ◽  
Crystalline Phases ◽  
Tio2 Photocatalysts ◽  
Tio2 Anatase ◽  
Synthesis Parameters ◽  
Calcination Step

This work reviews an eco-friendly process for producing TiO2 via colloidal aqueous sol–gel synthesis, resulting in crystalline materials without a calcination step. Three types of colloidal aqueous TiO2 are reviewed: the as-synthesized type obtained directly after synthesis, without any specific treatment; the calcined, obtained after a subsequent calcination step; and the hydrothermal, obtained after a specific autoclave treatment. This eco-friendly process is based on the hydrolysis of a Ti precursor in excess of water, followed by the peptization of the precipitated TiO2. Compared to classical TiO2 synthesis, this method results in crystalline TiO2 nanoparticles without any thermal treatment and uses only small amounts of organic chemicals. Depending on the synthesis parameters, the three crystalline phases of TiO2 (anatase, brookite, and rutile) can be obtained. The morphology of the nanoparticles can also be tailored by the synthesis parameters. The most important parameter is the peptizing agent. Indeed, depending on its acidic or basic character and also on its amount, it can modulate the crystallinity and morphology of TiO2. Colloidal aqueous TiO2 photocatalysts are mainly being used in various photocatalytic reactions for organic pollutant degradation. The as-synthesized materials seem to have equivalent photocatalytic efficiency to the photocatalysts post-treated with thermal treatments and the commercial Evonik Aeroxide P25, which is produced by a high-temperature process. Indeed, as-prepared, the TiO2 photocatalysts present a high specific surface area and crystalline phases. Emerging applications are also referenced, such as elaborating catalysts for fuel cells, nanocomposite drug delivery systems, or the inkjet printing of microstructures. Only a few works have explored these new properties, giving a lot of potential avenues for studying this eco-friendly TiO2 synthesis method for innovative implementations.

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