Sol-Gel Synthesis and Characterization of Cubic Bismuth Zinc Niobium Oxide Nanopowders

Bismuth zinc niobium oxide (BZN) was successfully synthesized by a diol-based sol-gel reaction utilizing metal acetate and alkoxide precursors. Thermal analysis of a liquid suspension of precursors suggests that the majority of organic precursors decompose at temperatures up to 150°C, and organic free powders form above 350°C. The experimental results indicate that a homogeneous gel is obtained at about 200°C and then converts to a mixture of intermediate oxides at 350–400°C. Finally, single-phased BZN powders are obtained between 500 and 900°C. The degree of chemical homogeneity as determined by X-ray diffraction and EDS mapping is consistent throughout the samples. Elemental analysis indicates that the atomic ratio of metals closely matches a Bi1.5ZnNb1.5O7composition. Crystallite sizes of the BZN powders calculated from the Scherrer equation are about 33–98 nm for the samples prepared at 500–700°C, respectively. The particle and crystallite sizes increase with increased sintering temperature. The estimated band gap of the BZN nanopowders from optical analysis is about 2.60–2.75 eV at 500-600°C. The observed phase formations and measured results in this study were compared with those of previous reports.

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Sol-gel Synthesis, Magnetic and Structural Characterization of BaFe11.6–2xMxTixO19 (M=Co, Zn, Sn) Compounds.

MRS Proceedings ◽

10.1557/proc-755-dd6.7 ◽

2002 ◽

Vol 755 ◽

Author(s):

G. Mendoza-Suárez ◽

A.F. Fuentes ◽

J.I. Escalante-García ◽

O.E. Ayala-Valenzuela

Keyword(s):

Magnetocrystalline Anisotropy ◽

Sol Gel ◽

Treatment Temperature ◽

X Ray Diffraction ◽

X Ray ◽

Heat Treated ◽

Barium Ferrites ◽

Crystallite Sizes ◽

Sol Gel Synthesis

ABSTRACTSubstituted barium ferrites powders with Ti4+-M2+ (M = Co, Zn, Sn) cationic mixtures were prepared by a sol-gel route. The materials were heat-treated in the range 925–1000 °C and characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM) and vibrating sample magnetometry (VSM). The results showed that the effect of the substitution, x was to lower the coercivity (Hc), owing to the decrease of the magnetocrystalline anisotropy of the magnetoplumbite structure of the BaM. In this regard Sn-Ti substitutions tended to decrease Hc more rapidly than Zn-Ti and Ti-Co substitutions, in that order. Regarding the saturation magnetization (Ms), Zn-Ti mixtures showed slightly better Ms than Ti-Co substitutions; however, the Sn-Ti showed a more marked decrease as x increased. As revealed by SEM, the effect of the heat-treatment temperature was to increase the volume of multi-domain particles, following a Hc decrease due to grain coarsening. Contrarily, as a result of the improved crystallinity of the samples, as observed from the XRD peaks, Ms enhancement was recorded. Crystallite sizes decreased below 100 nm as x increased, although it was also dependent on the cationic mixture. In this respect Sn-Ti substitutions needed higher treatment temperatures to yield materials with adequate crystallinity and phase constitution.

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Sol-gel synthesis and characterization of Ag nanoparticles in ZrO2 thin films

Journal of Materials Research ◽

10.1557/jmr.2009.0314 ◽

2009 ◽

Vol 24 (8) ◽

pp. 2541-2546 ◽

Cited By ~ 7

Author(s):

Eisuke Yokoyama ◽

Hironobu Sakata ◽

Moriaki Wakaki

Keyword(s):

Thin Films ◽

Sol Gel ◽

Composite Films ◽

Dip Coating ◽

Molar Ratio ◽

X Ray Diffraction ◽

Silver Surface ◽

Molar Ratios ◽

Sol Gel Synthesis

ZrO2 thin films containing silver nanoparticles were prepared using the sol-gel method with Ag to Zr molar ratios [Ag]/[Zr] = 0.11, 0.25, 0.43, 0.67, 1.00, 1.50, and 2.33. After dip coating on glass substrate, coated films were annealed at 200 and 300 °C in air. X-ray diffraction peaks corresponding to crystalline Ag were observed, but a specific peak corresponding to ZrO2 was not observed. At the molar ratio [Ag]/[Zr] = 0.25, the particle size of Ag distributed broadly centered at 17 nm for an annealing temperature of 200 °C and at 25 nm for 300 °C. The films annealed in air at 200 °C showed an absorption band centered at 450 nm because of the silver surface plasmon resonance, whereas films heated at 300 °C in air caused a red shift of the absorption to 500 nm. The absorption peak was analyzed using the effective dielectric function of Ag-ZrO2 composite films modeled with the Maxwell-Garnett expression.

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Synthesis and Characterization of Niobium Oxide Nanoparticles, Polyindole and Nb2O5/Polyindole Nanocomposite

Asian Journal of Chemistry ◽

10.14233/ajchem.2020.22397 ◽

2020 ◽

Vol 32 (3) ◽

pp. 653-658

Author(s):

S. Anandhi ◽

D. Keerthika ◽

M. Leo Edward ◽

V. Jaisankar

Keyword(s):

Niobium Oxide ◽

Sol Gel ◽

Degree Of Crystallinity ◽

Oxide Nanoparticles ◽

Spectroscopic Techniques ◽

Crystallite Sizes ◽

Chemical Character ◽

Tga And Dsc ◽

Polymerization Method

In present work, polyindole-Nb2O5 nanocomposite was synthesized and characterized by various analytical methods. Niobium oxide nanoparticles were prepared by sol gel method. Polyindole and Nb2O5 nanocomposites was prepared by chemical polymerization method and the morphology of Nb2O5 nanoparticles, polyindole and the nanocomposite was studied by SEM. The chemical structure of Nb2O5 nanoparticle, polyindole and the nanocomposite was characterized by UV-visible, FTIR and NMR spectroscopic techniques. Elemental composition and chemical character was analyzed by the use of EDAX technique. The X-ray powder diffraction technique was used to determine the degree of crystallinity and crystallite sizes. Thermal analysis such as TGA and DSC showed that the conducting polymers in the nanocomposites were stable even at high temperatures.

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Sol-Gel Synthesis and Characterization of Nanocrystalline Bi4Ti3O12 Powders

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.997.359 ◽

2014 ◽

Vol 997 ◽

pp. 359-362 ◽

Cited By ~ 1

Author(s):

Chun Hong Ma ◽

Xue Lin ◽

Liang Wang ◽

Yong Sheng Yan

Keyword(s):

Phase Inversion ◽

Bismuth Titanate ◽

Sol Gel ◽

Tetrabutyl Titanate ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Sol Gel Synthesis ◽

Source Materials

Nanocrystalline bismuth titanate (Bi4Ti3O12; BTO) powders were successfully prepared by the sol-gel method, using bismuth nitrate (Bi(NO3)3·5H2O) and tetrabutyl titanate (Ti(OC4H9)4) as source materials, acetic anhydride and ethanediol as solvents. The thermal decomposition and phase inversion process of the gel precursors were studied by using differential thermal analysis (DTA). The crystal structures and microstructures of BTO powders were investigated by using x-ray diffraction (XRD), and transmission electron microscope (TEM). The crystallization of amorphous bismuth titanate has been discussed. The effect of sintering temperature on the structure and morphology of BTO was investigated. At 644 oC and above, BTO powder undergoes a phase transformation from tetragonal to orthorhombic. At 900 oC, the purified orthorhombic BTO nanocrystals were obtained.

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Sol-Gel Synthesis and Structural Characterization of Nano-Thiamine Hydrochloride Structure

ISRN Nanotechnology ◽

10.1155/2013/815071 ◽

2013 ◽

Vol 2013 ◽

pp. 1-4 ◽

Cited By ~ 2

Author(s):

Salameh Azimi

Keyword(s):

Sol Gel ◽

Catalyst Support ◽

Morphological Observation ◽

Glassy Matrix ◽

Thiamine Hydrochloride ◽

Water Mixture ◽

X Ray Diffraction ◽

Silica Source ◽

Sol Gel Synthesis

The study presents the synthesis of nano-thiamine hydrochloride structure (NTH) using sol-gel method by hydrolysis of tetraethyl orthosilicate with ethanol and water mixture as silica source and nitric acid as catalyst support in which thiamine hydrochloride nanocrystals were dispersed in the silica glassy matrix. The synthesized nanocomposite was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and differential thermal analysis (DTA). The morphological observation of the SEM results reveals that the nano-thiamine hydrochloride composites are in the range of 5–15 nm in size.

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Efficiency of TiO2 catalyst supported by modified waste fly ash during photodegradation of RR45 dye

Science and Engineering of Composite Materials ◽

10.1515/secm-2019-0017 ◽

2019 ◽

Vol 26 (1) ◽

pp. 292-300 ◽

Cited By ~ 3

Author(s):

Vanja Gilja ◽

Zvonimir Katančić ◽

Ljerka Kratofil Krehula ◽

Vilko Mandić ◽

Zlata Hrnjak-Murgić

Keyword(s):

Fly Ash ◽

Gas Adsorption ◽

Sol Gel ◽

Efficiency Evaluation ◽

X Ray Diffraction ◽

X Ray ◽

Sol Gel Synthesis ◽

Adsorption Desorption

AbstractThe waste fly ash (FA) material was subjected to chemical treatment with HCl at elevated temperature for a different time to modify its porosity. Modified FA particles with highest surface area and pore volume were further used as a support for TiO2 catalyst during FA/TiO2 nanocomposite preparation. The nanocomposite photocatalysts were obtained by in situ sol–gel synthesis of titanium dioxide in the presence of FA particles. To perform accurate characterization of modified FA and FA/TiO2 nanocomposite photocatalysts, gas adsorption-desorption analysis, X-ray diffraction, scanning electron microscopy, UV/Vis and Infrared spectroscopy were used. Efficiency evaluation of the synthesized FA/TiO2 nanocomposites was performed by following the removal of Reactive Red 45 (RR45) azo dye during photocatalytic treatment under the UV-A irradiation. Photocatalysis has been carried out up to five cycles with the same catalysts to investigate their stability and the possible reuse. The FA/TiO2 photocatalyst showed very good photocatalytic activity and stability even after the fifth cycles. The obtained results show that successfully modified waste fly ash can be used as very good TiO2 support.

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Two Steps Synthesis of Quaternary Metal Titanate of Ba2NiTi5O13 and Characterization

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.364.353 ◽

2011 ◽

Vol 364 ◽

pp. 353-358

Author(s):

Yin Chew Ker ◽

Abu Bakar Mohamad

Keyword(s):

Monoclinic Phase ◽

Sol Gel ◽

Thermo Gravimetric Analysis ◽

Gravimetric Analysis ◽

X Ray Diffraction ◽

Thermo Gravimetric ◽

Pure Phase ◽

Average Size ◽

Sol Gel Synthesis

Quaternary metal oxide of Ba2NiTi5O13was synthesized by using two-step sol-gel method. Excess of titanium dioxide obtained from the first step of sol-gel synthesis, were subsequently reacted in second step of sol-gel synthesis in order to produce Ba2NiTi5O13monoclinic phase. Calcination temperature of 900 °C for as long as 8 hours was needed for obtaining pure phase of Ba2NiTi5O13. Homogenous micron sized particles of Ba2NiTi5O13with average size of 0.10 μm and narrow distribution were observed using Scanning Electron Microscopy (SEM). Besides, porous structures can also be seen distributed across the surface of the particles of Ba2NiTi5O13particles. Characterization of monoclinic phase of Ba2NiTi5O13was described based on the investigations of X-Ray Diffraction (XRD), Fourier Transform Infrared (FTIR) and Thermo Gravimetric Analysis (TGA).

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Anomaly in thermal characterization of CaxMg1-xNb2O6 (x =0,0.4,0.6,1) towards LTCC applications

Journal of Research in Physics ◽

10.2478/v10242-012-0009-8 ◽

2012 ◽

Vol 36 (1) ◽

pp. 13-19

Author(s):

Jyotirmayee Satapathy ◽

M.V.Ramana Reddy

Keyword(s):

Thermal Instability ◽

Dielectric Material ◽

Raw Materials ◽

Sol Gel ◽

Thermal Characterization ◽

Extensive Study ◽

X Ray Diffraction ◽

X Ray ◽

Sol Gel Synthesis

Abstract Low temperature co-fired ceramics (LTCC), being the most advantageous technology related to the multilayer substrates for various applications, demands an extensive study of raw materials. In the present work, a series of CaxMg1−xNb2O6 (x =0, 0.4, 0.6, 1.0) were prepared using sol-gel synthesis route and sintered at a temperature of 900°C to study its applicability for LTCC technology. The phase formation has been confirmed using X-ray diffraction. Thermal properties like thermal conductivity and thermal expansion, which are very important aspects as the former defines the heat flow to avoid thermal instability in the layers and the latter provides the dimensional congruency of the dielectric material and the conductors, are studied here over high temperature range up to the firing temperature. Although the values are quite satisfactory from the application point view, the results have showed an anomaly over temperature. The anomalous thermal behavior was further analyzed using TG-DTA.

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

ALCHEMY Jurnal Penelitian Kimia ◽

10.20961/alchemy.13.2.4348.133-146 ◽

2017 ◽

Vol 13 (2) ◽

pp. 133 ◽

Cited By ~ 1

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

The aim of this work was to determine the effect of calcination temperature on the characteristics of Fe2O3 nanoparticles (NPs) in sol-gel synthesis. The obtained Fe2O3 NPs was then used as material for preparation of Fe2O3-water nanofluids. Nanofluids is a mixture between basic fluid like water and 1 - 100 nm solid particles (nanoparticles). Nanoparticles of Fe2O3 have been synthesized from the local mineral Jarosite using sol-gel method by using starfruit (Averrhoa bilimbi) 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 Fe2O3 was relevant with the JCPDS data No. 33-0664 for α-Fe2O3 with hexagonal crystallite system. The crystallite size (Scherrer’s Equation) of obtained α-Fe2O3 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 Fe2O3 NPs at temperature of 500 ºC, 600 ºC and 700 ºC was 45.45 m2/g; 26.91 m2/g and 17.51 m2/g, respectively. Fe2O3-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 Fe2O3-water nanofluids was higher than the viscosity of water. The critical heat flux (CHF) value of water-Fe2O3 nanofluids was higher than the CHF water. The highest CHF value for nanofluids was obtained by using α-Fe2O3 nanoparticles with calcination temperature of 600 ºC which 34.99 % of increment compare to the base fluid (water).

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Sol-gel synthesis and study of neodymium substitution effects in Co-Al-Nd-O system with possible applications as novel inorganic pigments

Open Chemistry ◽

10.2478/s11532-012-0072-8 ◽

2012 ◽

Vol 10 (5) ◽

pp. 1574-1583 ◽

Cited By ~ 1

Author(s):

Dalia Jonynaite ◽

Darius Jasaitis ◽

Rimantas Raudonis ◽

Algirdas Selskis ◽

Remigijus Juskenas ◽

...

Keyword(s):

Sol Gel ◽

Substitution Effects ◽

X Ray Diffraction ◽

X Ray ◽

Force Microscopy ◽

Atomic Force ◽

Sol Gel Process ◽

New Compounds ◽

Sol Gel Synthesis

AbstractIn the present work, the formation of cobalt aluminium spinel (CoAl2O4) as well as novel cobalt neodymium-aluminates with nominal compositions of CoAl1.75Nd0.25O4, CoAl1.5Nd0.5O4 and CoAlNdO4 by an aqueous sol-gel process and the sinterability of the products are investigated. The metal ions, generated by dissolving starting materials of metals in the diluted acetic acid were complexed by 1,2-ethanediol to obtain the precursors for the mixed metal ceramics. The phase purity of the synthesized compounds was characterized by powder X-ray diffraction analysis and infrared spectroscopy. The microstructural evolution and morphological features of the products were studied by scanning electron microscopy and atomic force microscopy, which together with the optical characterization of these new compounds showed that the sol-gel-derived materials could be successfully used as effective cobalt-based ceramic pigments.

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