DIFFERENT MORPHOLOGIES OFTiO2NANOSTRUCTURES IN ACIDIC AND BASIC SOL–GEL METHOD

NANO ◽  
2010 ◽  
Vol 05 (05) ◽  
pp. 279-285 ◽  
Author(s):  
M. H. IMANIEH ◽  
Y. VAHIDSHAD ◽  
P. NOURPOUR ◽  
S. SHAKESI ◽  
K. SHABANI
Keyword(s):  
Ph Value ◽  
Sol Gel ◽  
Simple Method ◽  
Gel Method ◽  
Sol Gel Method ◽  
New Process ◽  
Nanocrystalline Titanium ◽  
Acidic Conditions ◽  
Nanocrystalline Titanium Dioxide ◽  
First Time

In this research, nanocrystalline titanium dioxide (TiO2) particles were prepared by a modified alkoxide technique under basic and acidic conditions at room temperatures. A simple method for preparing different morphology of TiO2has been developed. The reaction condition was used to control the crystalline size, phase and morphology of the TiO2nanostructures. In this process by adjusting the Rw(water to precursor ratio) and pH value the hydrolysis and condensation reactions were controlled. This led to the development of a new process to produce TiO2nanorod (for the first time by sol–gel method) at high pH value (basic) while the water content was sufficient whereas at low pH value (acidic) nanosphere TiO2were obtained. The powders were characterized by DTA, XRD, FE-SEM and UV–vis techniques and their physical properties were compared.

Synthesis, crystal structure and photoluminescence properties of Eu2+-activated RbCaGd(PO4)2 phosphors

RSC Advances ◽  
2016 ◽  
Vol 6 (14) ◽  
pp. 11211-11217 ◽  
Author(s):  
Xue Chen ◽  
Qidi Wang ◽  
Fengzhu Lv ◽  
Paul K. Chu ◽  
Yihe Zhang
Keyword(s):  
Crystal Structure ◽  
Sol Gel ◽  
Dipole Interaction ◽  
Concentration Quenching ◽  
Photoluminescence Properties ◽  
Gel Method ◽  
Sol Gel Method ◽  
First Time

RbCaGd(PO4)2:Eu2+ was prepared by the Pechini-type sol–gel method. The crystal structure was determined in the first time. The dipole–dipole interaction plays a major role in the mechanism of concentration quenching of Eu2+ in this phosphor.

The Research on ODS Iron Powder by Sol-Gel Method

2012 ◽  
Vol 476-478 ◽  
pp. 1146-1149 ◽  
Author(s):  
Xiao Yu ◽  
Zhi Meng Guo ◽  
Jun Jie Hao ◽  
Wei Wei Yang
Keyword(s):  
Mechanical Alloying ◽  
Iron Powder ◽  
Ferritic Steel ◽  
Ph Value ◽  
Sol Gel ◽  
Oxide Dispersion Strengthened ◽  
Steel Powder ◽  
Raw Material ◽  
Gel Method ◽  
Sol Gel Method

Oxide dispersion strengthened (ODS) ferritic steel which contains Y2O3 dispersion is one of the most promising candidates for fast neutron reactor cladding materials due to its excellent swelling resistance to neutron and superior creep resistance in high temperature. There are many ways to prepare ODS ferritic steel and the most commonly used method is mechanical alloying. However, ODS ferritic steel produced by the method of mechanical alloying is poor in the plasticity and impact property. Moreover, the anisotropies of structure and properties are obvious in the follow-up processing. In this paper, in order to reduce the cost, iron powder is used as raw material instead of ferritic steel powder. The complexing sol-gel method is adopted to prepare ODS iron-powder. There are many advantages of the sol-gel method such as the small size of disperse phase and the high uniformity. Besides, it is easy to control the conditions of reaction such as the water content, the bath temperature and the PH value. The gel-coated iron powder can be prepared under the appropriate environmental conditions. Then, we can obtain iron powder with Y2O3 dispersion after heating and reducing the gel-coated iron powder. By the spark plasma sintering(SPS), the ODS iron powder can be densified and we can observe the microstructure and test the performance. The results reveal the Y2O3 dispersion of ODS iron-powder by sol-gel method is uniform and the mechanical property is excellent.

scholarly journals Photocatalytic degradation of methylene blue under natural sunlight using iron titanate nanoparticles prepared by a modified sol–gel method

2020 ◽  
Vol 7 (9) ◽  
pp. 200708
Author(s):  
Z. Z. Vasiljevic ◽  
M. P. Dojcinovic ◽  
J. D. Vujancevic ◽  
I. Jankovic-Castvan ◽  
M. Ognjanovic ◽  
...  
Keyword(s):  
Methylene Blue ◽  
Photocatalytic Degradation ◽  
Sol Gel ◽  
Oh Radicals ◽  
Simple Method ◽  
Gel Method ◽  
Natural Sunlight ◽  
Sol Gel Method ◽  
Light Region ◽  
Iron Titanate

The aim of this work was to synthesize semiconducting oxide nanoparticles using a simple method with low production cost to be applied in natural sunlight for photocatalytic degradation of pollutants in waste water. Iron titanate (Fe 2 TiO 5 ) nanoparticles with an orthorhombic structure were successfully synthesized using a modified sol–gel method and calcination at 750°C. The as-prepared Fe 2 TiO 5 nanoparticles exhibited a moderate specific surface area. The mesoporous Fe 2 TiO 5 nanoparticles possessed strong absorption in the visible-light region and the band gap was estimated to be around 2.16 eV. The photocatalytic activity was evaluated by the degradation of methylene blue under natural sunlight. The effect of parameters such as the amount of catalyst, initial concentration of the dye and pH of the dye solution on the removal efficiency of methylene blue was investigated. Fe 2 TiO 5 showed high degradation efficiency in a strong alkaline medium that can be the result of the facilitated formation of OH radicals due to an increased concentration of hydroxyl ions.

Preparation of Tungsten-Doped VO2 (M) Nanoparticles through Sol-Gel Method and Hydrothermal Synthesis

2014 ◽  
Vol 881-883 ◽  
pp. 960-963 ◽  
Author(s):  
Ji Qi ◽  
Bin Zhao ◽  
Naisen Yu ◽  
Chen Niu ◽  
Guan Gran Sun
Keyword(s):  
Phase Transition ◽  
Vanadium Dioxide ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Gel Method ◽  
X Ray ◽  
Sol Gel Method ◽  
New Process ◽  
Scanning Electron

A new process was developed for synthesizing tungsten-doped vanadium dioxide VO2(M) from ammonium metavanadate. The process includes obtaining V2O5by pyrolysing NH4VO3, doping tungsten in V2O5by sol-gel method, and reducing V2O5to VO2(M) with hydrazine by hydrothermal method. X-ray diffraction (XRD), scanning electron microscopy (SEM) and differential scanning calorimetry (DSC) were applied to characterizing the product. The experimental results indicated that tungsten doped VO2(M) nanoparticles were successfully synthesized. The product VO2(M) presents mainly rod-like and block-like morphology. The phase transition temperature decreases with tungsten doped amount increasing, the phase transition takes place over the range from 36.23°C to 62.16°C and the largest enthalpy of the phase transition is 16.24J/g.

scholarly journals Effect of pH and annealing temperature on the structural and magnetic properties of cerium-substituted yttrium iron garnet powders produced by the sol-gel method

2016 ◽  
Vol 34 (2) ◽  
pp. 362-367 ◽  
Author(s):  
I. Yarici ◽  
M. Erol ◽  
E. Celik ◽  
Y. Ozturk
Keyword(s):  
Magnetic Properties ◽  
Yttrium Iron Garnet ◽  
Annealing Temperature ◽  
Ph Value ◽  
Sol Gel ◽  
Chelating Agent ◽  
Yttrium Iron ◽  
Gel Method ◽  
Sol Gel Method ◽  
Iron Garnet

AbstractCerium substituted yttrium iron garnet (Ce0.2Y2.8Fe5O12; Ce-YIG) nanoparticles were produced via the sol-gel method from solutions of Ce-, Y- and Fe-based precursors, a solvent and a chelating agent. The solutions were dried at 200°C and heat treated at temperatures between 800 °C and 1400°C for 3 h in air. The effects of pH and annealing temperature on the structure, phase formation, magnetic properties and crystallite size were investigated. A cubic YIG phase was obtained for the sample annealed at 1400 °C. The presented results showed that the pH value of the starting solution affects the crystal size and consequently, the saturation magnetization.

Preparation of Superhydrophilic Polyethersulfone by Sol-Gel Method

2013 ◽  
Vol 785-786 ◽  
pp. 1547-1550
Author(s):  
Guang Fen Li ◽  
Jin Chao Zhang ◽  
Xu Dong Sun
Keyword(s):  
Photoelectron Spectroscopy ◽  
Sol Gel ◽  
Contact Angle Measurement ◽  
Angle Measurement ◽  
Sem Images ◽  
Simple Method ◽  
Gel Method ◽  
Sol Gel Method ◽  
Atomic Force ◽  
Infrared Spectral

Here a simple method was developed to fabricate hydrophilic Polyethersulphone film via a sol-gel process. The correspondent hydrophilicity was evaluated by infrared spectral analysis, X-ray photoelectron spectroscopy, the contact angle measurement, atomic force microscope and scanning electron microscope analysis, respectively. Both FTIR and XPS analysis indicated that the film surfaces have a relatively dense sol layer, which favors to become hydrophilic. AFM analysis demonstrated that the higher hydrophilicity was mainly attributed to the surface roughness, while SEM images show that the micro/nanometer crater-like protrusions appears on the film surfaces, whereas the spongy structures & the finger-like structures appear in cortex and intermediate layer respectively. This leads to the hydrophilic film forming after film being treated by sol-gel method.

Synthesis of Pure Hydroxyapatite (Ca10(PO4)6(OH)2) by the Sol–Gel Method and the Antibiotic Loaded in the Presence of Natural Polymer for the Application of Drug Delivery

2018 ◽  
Vol 24 (8) ◽  
pp. 5523-5526 ◽  
Author(s):  
B Shalini ◽  
A. Ruban Kumar ◽  
A. Mary Saral
Keyword(s):  
Ph Value ◽  
Drug Loading ◽  
Sol Gel ◽  
Calcium Nitrate ◽  
Average Crystallite Size ◽  
Ammonia Solution ◽  
Calcium Nitrate Tetrahydrate ◽  
Gel Method ◽  
Sol Gel Method ◽  
Nitrate Tetrahydrate

Hydroxyapatite (HAp) is the most widely accepted biomaterial for the repair and reconstruction of bone tissue defects. The current study is based on HAp was synthesized using sol–gel method. The drug was loaded in presence and absence of gelatin with pure HAp. Precursors like calcium nitrate tetrahydrate and diammonium hydrogen orthophosphate were used and ammonia solution was added to maintain the pH value at 10.5 throughout the reaction. The synthesized HAp, drug loaded HAp and drug loaded HAp with gelatin were characterized using PXRD, FTIR, SEM, Drug loading, drug release studies. Results shows that the average crystallite size of the prepared HAp and drug loaded HAp with gelatin are 30 to 60 nm and 100 to 300 nm respectively was calculated using PXRD and morphology of pure HAp and drug loaded HAp with polymer was found using SEM. Drug loading and release percentage was calculated.

scholarly journals The Influence of the Compositions of Reactants on the Luminescence Intensity of Zn2SiO4: Mn Synthesized by Sol-Gel Method Using Hydrochloric Acid 

2021 ◽  
Vol 31 (1) ◽  
pp. 1-5
Keyword(s):  
Hydrochloric Acid ◽  
Luminescence Intensity ◽  
Ph Value ◽  
Phase 1 ◽  
Sol Gel ◽  
Molar Ratio ◽  
Rhombohedral Structure ◽  
Spherical Form ◽  
Gel Method ◽  
Sol Gel Method

The green emitting phosphor based on manganese activated zinc silicate was successfully synthesized by the sol – gel method using hydrochloric acid. The suitable molar ratio of the initial components is Zn(CH3COO)2: MnSO4: TEOS = 1.98: 0.02: 1 corresponding to the product formula Zn1.98Mn0,02SiO4. The suitable pH value for the gelation is 3, ratio of water phase: ethanol phase = 1:1 and the product when calcining the obtained gel at 10000C for 60 minutes has highest luminescence intensity. The synthesized phosphor consists of Zn2SiO4 with rhombohedral structure and emits a green light at the 525 nm wavelength when excited by the 325 nm UV radiation. The produced sample has spherical form with the particles size being 100 nm.

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