scholarly journals Influence of type of precursors on the sol-gel synthesis of the LaCoO3 nanoparticles

2014 ◽  
Vol 22 (1) ◽  
pp. 1-12 ◽  
Author(s):  
Nicoleta Cornei ◽  
Simona Feraru ◽  
Ion Bulimestru ◽  
Andrei Victor Sandu ◽  
Carmen Mita
Keyword(s):  
Crystal Structure ◽  
Sol Gel ◽  
Chelating Agent ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Sol Gel Synthesis ◽  
Perovskite Type ◽  
Type Crystal ◽  
Scanning Electron

Abstract Perovskite-type LaCoO3 was prepared by sol-gel method using nitrates / chlorides as precursors and citric acid as chelating agent. Chemical composition was obtained by means of EDX method. The structures of sintered samples were investigated by scanning electron microscopy (SEM), IR and XRD analysis. The results of X-ray diffraction indicated that the LaCoO3nanopowders obtained using nitrate as precursors had a rhombohedral perovskite-type crystal structure (S. G: R-3c), while that obtained using chloride as precursors had a mixture of LaCoO3, LaOCl and Co3O4. The all lanthanum cobaltites exhibit catalytic activity on the decomposition of hydrogen peroxide, ascribed to their higher surface and Co3+ concentration

scholarly journals Effect of Polymers (PEG and PVP) on Sol-Gel Synthesis of Microsized Zinc Oxide

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Thilagavathi Thirugnanam
Keyword(s):  
Sol Gel ◽  
Cost Effective ◽  
X Ray Diffraction ◽  
X Ray ◽  
Structural Modifications ◽  
Phase Pure ◽  
Sol Gel Synthesis ◽  
Polyethylene Glycol 6000 ◽  
Granular Morphology ◽  
Scanning Electron

Fibers irregular and seed-like microcrystalline ZnO were synthesized by using a cost-effective and low temperature aqueous sol-gel method. Various polymers, namely, polyethylene glycol 6000 (PEG 6000) and polyvinyl pyrrolidone (PVP), were used as structure directing agents. The samples were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The X-ray diffraction pattern revealed the formation of phase-pure ZnO micropowders. It is observed that the polymers play an important role in modifying the surface morphology and the size of the crystallites. A compact granular morphology is observed for the ZnO samples without polymer. The samples exhibit microparticles of size 100 nm for PVP and for PEG-mediated growth, whereas microporous corrugated morphology is observed for added PEG-mediated micropowder. FTIR study is used to confirm the structural modifications occurring in the polymers.

The Effect of Water Content on the Formation of TiO2 Nanotubes in Ethylene Glycol

2010 ◽  
Vol 173 ◽  
pp. 102-105 ◽  
Author(s):  
Khairul Arifah Saharudin ◽  
Srimala Sreekantan
Keyword(s):  
Crystal Structure ◽  
Aspect Ratio ◽  
Ethylene Glycol ◽  
Water Content ◽  
Anatase Phase ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Degradation Of Methyl Orange ◽  
Scanning Electron

In this paper, anodization of Ti foil was carried out in ethylene glycol (EG) containing 5 wt% NH4F solution and 0 to 1.5 wt% of water at 50 V for 60 min. The pH of the bath was kept constant at ~pH7. The crystal structure was studied by X-Ray Diffraction (XRD) analysis, and the morphology was observed via field emission scanning electron microscopy (FESEM). TiO2 nanotube with aspect ratio of 100 was obtained in EG containing less than 1wt % water. The nanotubes wall was very smooth. Increasing the water content > 1wt % results in short nanotubes of approximately 6.2μm with aspect ratio of 62. As anodized, nanotubes were amorphous and annealed at 400 °C promote 100 % anatase phase. Photocatalytic activity of the nanotubes produced at different water content was also evaluated by the degradation of methyl orange and the detail of the observation was discussed thoroughly in this paper.

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.

scholarly journals Undoped and Eu3+ Doped Magnesium-Aluminium Layered Double Hydroxides: Peculiarities of Intercalation of Organic Anions and Investigation of Luminescence Properties

Materials ◽  
2019 ◽  
Vol 12 (5) ◽  
pp. 736 ◽  
Author(s):  
Aurelija Smalenskaite ◽  
Lina Pavasaryte ◽  
Thomas Yang ◽  
Aivaras Kareiva
Keyword(s):  
Layered Double Hydroxides ◽  
Organic Anion ◽  
Sol Gel ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Organic Guests ◽  
Double Hydroxides ◽  
Scanning Electron

The Mg3/Al and Mg3/Al0.99Eu0.01 layered double hydroxides (LDHs) were fabricated using a sol-gel chemistry approach and intercalated with different anions through ion exchange procedure. The influence of the origin of organic anion (oxalate, laurate, malonate, succinate, tartrate, benzoate, 1,3,5-benzentricarboxylate (BTC), 4-methylbenzoate (MB), 4-dimethylaminobenzoate (DMB) and 4-biphenylacetonate (BPhAc)) on the evolution of the chemical composition of the inorganic-organic LDHs system has been investigated. The obtained results indicated that the type and arrangement of organic guests between layers of the LDHs influence Eu3+ luminescence in the synthesized different hybrid inorganic–organic matrixes. For the characterization of synthesis products X-ray diffraction (XRD) analysis, infrared (FTIR) spectroscopy, fluorescence spectroscopy (FLS), and scanning electron microscopy (SEM), were used.

scholarly journals Synthesis of lead-based 1212 and 3212 superconductors by an aqueous sol-gel method

2009 ◽  
Vol 7 (3) ◽  
pp. 362-368 ◽  
Author(s):  
Giedre Nenartaviciene ◽  
Ramunas Skaudzius ◽  
Rimantas Raudonis ◽  
Aivaras Kareiva
Keyword(s):  
Sol Gel ◽  
Xrd Analysis ◽  
Structural Features ◽  
Complexing Agents ◽  
X Ray Diffraction ◽  
X Ray ◽  
Resistivity Measurements ◽  
Ceramic Samples ◽  
Xrd Patterns ◽  
Sol Gel Synthesis

AbstractThe aqueous sol-gel synthesis technique for the preparation of (Pb,Sr)Sr2(Y,Ca)Cu2O7±x (Pb-1212) and (Pb2,Cu)Sr2(Y,Ca)Cu2O8±x (Pb-3212) superconductors using two different complexing agents, namely 1,2-ethanediol and tartaric acid was studied. The phase transformations, composition and micro-structural features in the polycrystalline samples were studied by powder X-ray diffraction analysis (XRD), infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). XRD analysis of the ceramic samples obtained by calcination of Pb-Sr-Y-Ca-Cu-O acetate-glycolate precursor gels in air, for 10 hours at 800°C and at 825°C, showed the presence of homogeneous Pb-1212 and Pb-3212 crystallites as major phases. The XRD patterns of the ceramics obtained from Pb-Sr-Y-Ca-Cu-O acetate-tartrate precursor gels, however, showed multiphasic character. The critical temperature of superconductivity (TC (onset)) observed by resistivity measurements were found to be 91 K and 75 K for Pb-1212 and Pb-3212 samples, respectively.

Characterizations and Crystal Structure of Er Ions Doped Titania Nanofibers

2012 ◽  
Vol 468-471 ◽  
pp. 294-297
Author(s):  
Ying Lu ◽  
Jin Zhong Hong ◽  
Chang Lu Shao ◽  
Xin Zhang ◽  
Ming Xing Lv ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Composite Nanofibers ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
X Ray ◽  
Novel Method ◽  
Doped Titania ◽  
Er Doped ◽  
Scanning Electron ◽  
Titania Nanofibers

A simple and novel method to synthesize Er ion doped titania was investigated. In this work, Er-doped titania nanofibers were prepared by the sol-gel method. Characterizations of the nanofibers were done by X-ray diffraction, scanning electron microscopy. The results suggest that crystal structures of Er-doped titania composite nanofibers were changed due to Er ions disturbing.

EFFECT OF EXCESS BISMUTH ON THE SYNTHESIS OF BISMUTH SILICATE (Bi4Si3O12) POLYCRYSTALS

2009 ◽  
Vol 23 (08) ◽  
pp. 2093-2099 ◽  
Author(s):  
J. KAEWKHAO ◽  
N. UDOMKAN ◽  
W. CHEWPRADITKUL ◽  
P. LIMSUWAN
Keyword(s):  
Crystal Structure ◽  
Grain Size ◽  
Electron Microscope ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
Bismuth Silicate ◽  
X Ray ◽  
Structure And Morphology ◽  
Crystallization Morphology ◽  
Scanning Electron

In this study, the effect of bismuth content on the crystal structure and morphology of bismuth silicate ( BSO:Bi 4 Si 3 O 12) polycrystals were investigated with X-ray diffraction (XRD) analysis and scanning electron microscope (SEM). BSO materials have been successfully prepared by the solid-state reaction. The BSO phase was crystallized at 950°C for 12 h. In summary, 10% of excess bismuth was found to be the optimum composition with respect to crystallization, morphology, and grain size.

Study of Sol-Gel Auto-Combustion Method Prepare Ni0.6-xZn0.4MgxFe2O4

2012 ◽  
Vol 463-464 ◽  
pp. 1052-1056
Author(s):  
Ai Xiang Zeng ◽  
Jun Yuan
Keyword(s):  
Crystal Structure ◽  
Zinc Ferrite ◽  
Single Phase ◽  
Sol Gel ◽  
Combustion Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Nickel Zinc ◽  
Auto Combustion ◽  
Scanning Electron

Ni0.6-xZn0.4MgxFe2O4were synthesized by sol-gel auto-combustion method with Zn(NO3.) 2 •6H2O. , Ni(NO3.) )2•6H2O. , Mg(NO3.) )2•6H2O. , Fe(NO3.) )3•9H2O. , COOO2. and NH3•H2O. X-ray diffraction (XRD) analysises show that the sample is single phase and the doping of magnesium makes no difference to nickel-zinc ferrite’s crystal structure; nickel-zinc ferrite has formed after auto-combustion. Scanning electron microscope analysises show that after sintered the sample’s size is more even and the doping of magnesium makes the size smaller and more even too.

Effect of Zinc Substitution on Microstructure and Antibacterial Properties of Cobalt Ferrite Nanopowders Synthesized by Sol-Gel Methods

2012 ◽  
Vol 535-537 ◽  
pp. 436-439 ◽  
Author(s):  
Noppakun Sanpo ◽  
James Wang ◽  
Christopher C. Berndt
Keyword(s):  
Crystal Structure ◽  
Electron Microscopy ◽  
Cobalt Ferrite ◽  
Zinc Concentration ◽  
Antibacterial Property ◽  
Sol Gel ◽  
Antibacterial Properties ◽  
Chelating Agent ◽  
X Ray ◽  
Scanning Electron

Zinc substituted cobalt ferrite nanopowders with the general formula Co(1-x)ZnxFe2O4(with x = 0, 0.3, 0.5, 0.7, and 1) were prepared via the sol-gel route using citric acid as a chelating agent. The influence of zinc concentration on the microstructure, crystal structure and antibacterial property of zinc substituted cobalt ferrite nanopowders has been systematically investigated. The microstructure and elemental composition were characterized using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX), respectively. Phase analysis of cobalt ferrite nanopowders was performed using X-ray diffractometry (XRD). The antibacterial properties of zinc substituted cobalt ferrite nanopowders were investigated. The results indicate that the substitution of zinc influences strongly the microstructure, crystal structure and antibacterial property of the cobalt ferrite nanopowders.

scholarly journals SYNTHESIS AND CHARACTERIZATION OF Fe2O3 NANOPARTICLES USING Averrhoa bilimbi AS BIOMATERIAL CHELATING AGENT FOR NANOFLUIDS APPLICATION

2017 ◽  
Vol 13 (2) ◽  
pp. 133 ◽  
Author(s):  
Arie Hardian ◽  
Alvi Aristia Ramadhiany ◽  
Dani Gustaman Syarif ◽  
Senadi Budiman
Keyword(s):  
Calcination Temperature ◽  
Sol Gel ◽  
Chelating Agent ◽  
Xrd Analysis ◽  
Solid Particles ◽  
X Ray Diffraction ◽  
Calcination Temperatures ◽  
Basic Fluid ◽  
Sol Gel Synthesis

<p>The aim of this work was to determine the effect of calcination temperature on the characteristics of Fe<sub>2</sub>O<sub>3</sub> nanoparticles (NPs) in sol-gel synthesis. The obtained Fe<sub>2</sub>O<sub>3 </sub>NPs was then used as material for preparation of Fe<sub>2</sub>O<sub>3</sub>-water nanofluids. Nanofluids is a mixture between basic fluid like water and 1 - 100 nm solid particles (nanoparticles). Nanoparticles of Fe<sub>2</sub>O<sub>3</sub> have been synthesized from the local mineral Jarosite using sol-gel method by using starfruit (<em>Averrhoa bilimbi</em>) extracts as the chelating agent. The calcination temperature was then varied from 500 ºC to 700 ºC for 5 hours. Based on the X-Ray Diffraction (XRD) analysis, the diffraction pattern of obtained Fe<sub>2</sub>O<sub>3</sub> was relevant with the JCPDS data No. 33-0664 for α-Fe<sub>2</sub>O<sub>3 </sub>with hexagonal crystallite system. The crystallite size (Scherrer’s Equation) of obtained α-Fe<sub>2</sub>O<sub>3</sub> nanoparticles at calcination temperatures of 500 ºC, 600 ºC and 700 ºC was 50 nm, 48 nm and 40 nm, respectively. The Surface Area of Fe<sub>2</sub>O<sub>3</sub> NPs at temperature of 500 ºC, 600 ºC and 700 ºC was 45.45 m<sup>2</sup>/g; 26.91 m<sup>2</sup>/g and 17.51 m<sup>2</sup>/g, respectively. Fe<sub>2</sub>O<sub>3</sub>-water nanofluids was relativly stable with zeta potential of -39.60 mV; -46.37 mV and -41.57 mV, respectively for 500 ºC, 600 ºC and 700 ºC calcination temperature. The viscosity of Fe<sub>2</sub>O<sub>3</sub>-water nanofluids was higher than the viscosity of water. The critical heat flux (CHF) value of water-Fe<sub>2</sub>O<sub>3</sub> nanofluids was higher than the CHF water. The highest CHF value for nanofluids was obtained by using α-Fe<sub>2</sub>O<sub>3</sub> nanoparticles with calcination temperature of 600 ºC which 34.99 % of increment compare to the base fluid (water).</p>

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