scholarly journals The Effect of Precursors Concentration on the Structure and Micromagnetic Properties of Ultrafine Iron Oxides Obtained by Sol-Gel Route

2016 ◽  
Vol 3 (1) ◽  
pp. 38-45
Author(s):  
V. Kotsyubynsky ◽  
A. Hrubiak ◽  
L. Mohnatska ◽  
M. Gasyuk ◽  
V. Moklyak
Keyword(s):  
Phase Composition ◽  
Composite Materials ◽  
Ir Spectroscopy ◽  
Sol Gel ◽  
Iron Nitrate ◽  
Colloidal Solutions ◽  
X Ray Diffraction ◽  
Magnetic Microstructure ◽  
Iron Citrate ◽  
X Ray

Nanodispersed composite materials -Fe2O3/-Fe2O3 were obtained by thermaldecomposition of iron citrate xerogel hydrate synthesized by iron nitrate and citrate acid solutionswith different colloidal solutions of Fe(NO3)39H2O and С6Н8О7 Н2О for different molar ratiobetween precursors. The influence of the precursors molar concentration and calcinationtemperature on the material phase composition, crystalline and magnetic microstructure, surfacecondition was studied. Methods of X-ray diffraction, Mössbauer spectroscopy, electron microscopyand IR - spectroscopy were used.

Synthesis, structure and thermal expansion of the phosphates M0.5+x M′x Zr2−x (PO4)3 (M, M′–metals in oxidation state +2)

2017 ◽  
Vol 89 (4) ◽  
pp. 523-533 ◽  
Author(s):  
Elena Asabina ◽  
Vladimir Pet’kov ◽  
Pavel Mayorov ◽  
Dmitriy Lavrenov ◽  
Igor Schelokov ◽  
...  
Keyword(s):  
Thermal Expansion ◽  
Thermal Treatment ◽  
Ir Spectroscopy ◽  
Microprobe Analysis ◽  
Electron Microprobe Analysis ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
X Ray ◽  
Structural Types ◽  
The Difference

AbstractThe phosphates M0.5+x M′x Zr2−x (PO4)3 (M–Ca, Mn, Co, Sr, Cd, Ba, Pb; M′–Mg, Mn, Co) were synthesized by sol-gel method with the following thermal treatment of reaction mixtures. X-ray diffraction, IR spectroscopy and electron microprobe analysis showed that the obtained phosphates crystallized in Sc2(WO4)3 (SW) and NaZr2(PO4)3 (NZP) structural types. Both types of crystal structures are based on a framework comprised of octahedra and tetrahedra, the difference between them is fragments orientation. Thermal expansion of the phosphates was studied in the temperature range 20–800°C. Some compounds were found to belong to low-expanding materials (αav ~2·10−6°C−1).

Biomorphic SiC Prepared from Carbonized Millet by Sol-Gel and Carbothermal Reduction Processing

2010 ◽  
Vol 152-153 ◽  
pp. 1683-1686
Author(s):  
Qing Wang ◽  
Ya Hui Zhang
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Silicon Carbide ◽  
Phase Composition ◽  
Carbothermal Reduction ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
X Ray ◽  
Carbon Template ◽  
Scanning Electron

Biomorphic silicon carbide (bioSiC) was prepared by high temperature pyrolysis and sol-gel and carbothermal reduction processing at 1600 oC. The morphology and microstructure of carbon-silica composites and purified bioSiC samples were characterized by scanning electron microscopy. The phase composition of the resulting sample was analyzed by X-ray diffraction. The results suggest that the bioSiC mainly consists of cubic ß-SiC, and principally replicates the shape and microstructure of the carbon template.

Biomorphic TiO2 Ceramics Prepared from Cotton Stalk

2012 ◽  
Vol 602-604 ◽  
pp. 526-529
Author(s):  
Qing Wang ◽  
Lin Zhang ◽  
Ya Hui Zhang
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Phase Composition ◽  
High Temperature ◽  
Sol Gel ◽  
Cotton Stalk ◽  
X Ray Diffraction ◽  
X Ray ◽  
Carbon Template ◽  
Scanning Electron

Biomorphic TiO2 was prepared by high temperature pyrolysis and a modified sol-gel route. The morphology and microstructure of TiO2 samples were characterized by scanning electron microscopy. The phase composition of the resulting sample was analyzed by X-ray diffraction. The results suggest that the biomorphic TiO2 mainly consists of rutile TiO2, and replicates the shape and part microstructure of the carbon template.

Preparation and Characterization of N Doped TiO2/ Sepiolite Composite Materials

2011 ◽  
Vol 284-286 ◽  
pp. 597-600
Author(s):  
Dai Mei Chen ◽  
Hai Peng Ji ◽  
Jian Xin Wang ◽  
Jian Chen ◽  
Xin Long Luan ◽  
...  
Keyword(s):  
Composite Materials ◽  
Photoelectron Spectroscopy ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
X Ray ◽  
Nitrogen Doped ◽  
Nitrogen Contents ◽  
Scanning Electron ◽  
Oxygen Atoms

Nitrogen doped TiO2/sepiolite composite materials (N-TiO2/sep) with different nitrogen contents were prepared by a sol-gel method and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), respectively. XRD and SEM results showed that anatase-TiO2nanoparticles were distributed homogenously on the surface of sepiolite. XPS revealed that N atoms could incorporate into the lattice of anatase TiO2substituting the oxygen atoms sites of oxygen atoms.

Morphology and Phase Composition of Sol-Gel Derived Aluminum Borate Nanowhiskers

2015 ◽  
Vol 659 ◽  
pp. 121-126 ◽  
Author(s):  
Pat Sooksaen
Keyword(s):  
Fourier Transform ◽  
Phase Composition ◽  
Sol Gel ◽  
Molar Ratio ◽  
Aluminum Borate ◽  
X Ray Diffraction ◽  
X Ray ◽  
Higher Temperature ◽  
Sol Gel Synthesis ◽  
Scanning Electron

Aluminium borate nanowhiskers with varying aspect ratio were synthesized via sol–gel synthesis. The morphology of aluminum borate (Al4B2O9 and Al18B4O33) nanowhiskers could be controlled by varying the aluminum to boron (Al:B) molar ratio in the sol–gel derived precursors. Sintering temperatures (850 and 1100°C) and sintering times (4 and 32 hours) also affected the phase composition and size of the nanowhiskers. Citric acid was also added in the sol–gel derived precursors as a surface stabilizer for obtaining uniform finely dispersed nanostructures. Fine nanowhiskers were obtained by the calcination at 850°C, whereas higher temperature of 1100°C led to thicker and longer nanowhiskers and became rod-like crystals. The morphology and phase composition were investigated by field emission scanning electron microscope and X-ray diffraction. Chemical bond vibrations in the synthesized nanowhiskers were investigated by Fourier-transform infrared spectroscopy.

IMPROVED MAGNETIC PROPERTIES OF Sm COMBINING Co OR/AND Zn SUBSTITUTED BARIUM M-TYPE HEXAFERRITES

2012 ◽  
Vol 26 (26) ◽  
pp. 1250141 ◽  
Author(s):  
Y. B. HAN ◽  
J. SHA ◽  
L. N. SUN ◽  
Q. TANG ◽  
Q. LU ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Phase Composition ◽  
Magnetocrystalline Anisotropy ◽  
Sol Gel ◽  
Combustion Process ◽  
X Ray Diffraction ◽  
X Ray ◽  
Barium Hexaferrites ◽  
Auto Combustion ◽  
Magnetic Dilution

Sm (Co or/and Zn) substituted nanocrystalline barium hexaferrites were synthesized by the sol–gel auto-combustion process, then X-ray diffraction (XRD) and vibrating sample magnetometer (VSM) were used to characterize and discuss the phase composition and the magnetic properties of the as-prepared barium hexaferrites. All results showed that the phase composition and magnetic properties were closely related to the doping elements and x. Owing to hyperfine field, canting spin, magnetic dilution and impurity phases, the saturation magnetization (Ms) of all samples increased firstly, and then decreased. Considering the crystallization, the magnetocrystalline anisotropy and the ions occupancy, the doping elements and x critically affected the coercivity (Hc). Compared the magnetic properties of all the samples, it is concluded that Zn 2+ and Co 2+ influenced each other and Zn 2+ occupied 4f2 sites prior to Co 2+, which led to the increase of Ms and the decrease of Hc.

Preparation of Al2O3/MgO Nano-Composite Particles for Bio-Applications

2020 ◽  
Vol 38 (4A) ◽  
pp. 586-593
Author(s):  
Hayder A. Sallal ◽  
Alla A. Abdul-Hameed ◽  
Farhad. M. Othman
Keyword(s):  
Composite Materials ◽  
Sol Gel ◽  
Particle Size Analysis ◽  
Size Analysis ◽  
Composite Particles ◽  
X Ray Diffraction ◽  
Nano Composite ◽  
X Ray ◽  
Electron Microscopy Analysis ◽  
Microscopy Analysis

This study describes the preparation and study of the properties of Nano composite particles prepared in a sol-gel method which consists of two materials (Αl2Ο3-MgΟ). The powder was evaluated by x-ray diffraction analysis, scanning electron microscopy analysis (SEM), particle size analysis, and energy dispersive x-ray analysis (EDX) and antibacterial test. The evaluation results of the nanocomposite particles shows a good distribution of the chemical composition between aluminum oxide and magnesium oxide, smoothness in particles  size where it reached to (54.9, 59.8) nm at calcination in (550 0C and 850 0C) respectively, formation of different shapes of nanoparticles and different  phases of the Αl2Ο3 particles (kappa and gamma) and nanopowder have well antibacterial action, Therefore, this reflects the efficiency of the proposed method to manufacture the nanocomposite powder and the possibility of using this powder as a strengthening material for the composite materials and using these composite materials in bio applications, especially in the fabrication of artificial limbs.

Study of the Hydrophobic Properties of the Surface of an Enamel Material

2014 ◽  
Vol 789 ◽  
pp. 178-182 ◽  
Author(s):  
Li Yun Chen ◽  
Qian Qian Fang ◽  
Wei Zhong Jiang ◽  
Xiao Ping Liao ◽  
Jia Yi Ye ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Contact Angle ◽  
Composite Materials ◽  
Sol Gel ◽  
Enamel Surface ◽  
X Ray Diffraction ◽  
Hydrophobic Properties ◽  
X Ray ◽  
Scanning Electron

The hydrophobic properties of the surface of an enamel material are reported in this paper. By using a sol-gel method and with tetraethoxysilane as the precursor which is combined with dimethyldichlorosilane (DDS), the films composed of DDS-SiO2nanoparticle composite materials were prepared on an enamel surface, with the droplet’s contact angle increased, and the properties of the enamel surface changed from hydrophilic to hydrophobic. The properties were tested, the hydrophobic mechanism was studied based on the investigation of the microstructure and the crystal structures of the film by scanning electron microscopy, X-ray diffraction and infrared spectrum analysis.

Effects of Solvent on the Phase Composition and Microstructure of ZrSiO4 Film

2015 ◽  
Vol 1104 ◽  
pp. 119-124
Author(s):  
Fang Cao ◽  
Ting Chen ◽  
Wei Hui Jiang ◽  
Jian Min Liu ◽  
Jian Rui Zha ◽  
...  
Keyword(s):  
Phase Composition ◽  
Sol Gel ◽  
Dimethyl Formamide ◽  
X Ray Diffraction ◽  
Zirconium Tetrachloride ◽  
High Quality ◽  
Great Stability ◽  
X Ray ◽  
Zirconium Silicate ◽  
Scanning Electron

Zirconium silicate thin film was prepared via a novel non-hydrolytic sol-gel (NHSG) process at low temperature using zirconium tetrachloride (ZrCl4) and tetraethoxysilane (TEOS) as precursors. The phase composition and the microstructure of samples were characterized by X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM), respectively. The results demonstrate that pure ZrSiO4 film can be synthesized by using ethanol and isopropanol as solvent rather than dimethyl formamide (DMF) and dimethyl nylon acid (DBE) which cause impurity ZrO2. However, only ethanol can achieved smooth and dense ZrSiO4 film. The viscosity results suggest that the sol with ethanol has great stability. With a pulling rate of 1.0 mm s-1, a high quality ZrSiO4 film was prepared after drying at 50 oC for 2 h and calcination at 850 °C with a heating rate of 1.0 °C min-1.

Morphology, Structure and Corrosion Resistance of Nano-Enamel Coating Changed on Ti-6Al-4V Alloy

2017 ◽  
Vol 893 ◽  
pp. 309-312
Author(s):  
Yu Lin Li ◽  
Zhe Rui Huang ◽  
Qing Dong Zhong ◽  
Chen Xiao ◽  
Hui Li ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Phase Composition ◽  
Mild Steel ◽  
Potentiodynamic Polarization ◽  
Enamel Coating ◽  
Open Circuit Potential ◽  
Sol Gel ◽  
Open Circuit ◽  
X Ray Diffraction ◽  
X Ray

Using a sol-gel method and impregnation technology to produce nanoenamel coating on polished Ti-6Al-4V alloy. The morphology, structure and phase composition of nanoenamel coatings modified on mild steel were identified with X-ray diffraction (XRD), scanning electro microscopy (SEM) and tested by some electrochemical methods, such as open circuit potential and potentiodynamic polarization testing [1]. All of these method can select the samples which perform the best corrosion resisitance.

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