Sol-Gel Synthesis of the Double Perovskite Sr2FeMoO6 by Microwave Technique

The effect of microwave radiation on the hydrothermal synthesis of the double perovskite Sr2FeMoO6 has been studied based on a comparison of the particle size and structural characteristics of products from both methods. A temperature, pressure, and pH condition screening was performed, and the most representative results of these are herein presented and discussed. Radiation of microwaves in the hydrothermal synthesis method led to a decrease in crystallite size, which is an effect from the reaction temperature. The particle size ranged from 378 to 318 nm when pH was 4.5 and pressure was kept under 40 bars. According to X-ray diffraction (XRD) results coupled with the size-strain plot method, the product obtained by both synthesis methods (with and without microwave radiation) have similar crystal purity. The Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectroscopy (EDS) techniques showed that the morphology and the distribution of metal ions are uniform. The Curie temperature obtained by thermogravimetric analysis indicates that, in the presence of microwaves, the value was higher with respect to traditional synthesis from 335 K to 342.5 K. Consequently, microwave radiation enhances the diffusion and nucleation process of ionic precursors during the synthesis, which promotes a uniform heating in the reaction mixture leading to a reduction in the particle size, but keeping good crystallinity of the double perovskite. Precursor phases and the final purity of the Sr2FeMoO6 powder can be controlled via hydrothermal microwave heating on the first stages of the Sol-Gel method.

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Review on the Synthesis Methods of Nano-Tungsten Oxide Dihydrate Colloid

MATEC Web of Conferences ◽

10.1051/matecconf/202133503008 ◽

2021 ◽

Vol 335 ◽

pp. 03008

Author(s):

Khizar Mushtaq ◽

Pui May Chou ◽

Chin Wei Lai

Keyword(s):

Particle Size ◽

Tungsten Oxide ◽

Sol Gel ◽

Synthesis Method ◽

Transition Element ◽

Cost Effective ◽

Processing Parameters ◽

Synthesis Methods ◽

Cost Effective Method ◽

Future Work

Tungsten being a transition element, forms oxide compounds of various oxidation states that enables it to form nanocolloids of tungsten oxide dihydrate. Multiple methods have been used in recent years to synthesize nano tungsten oxide dihydrate, including sol-gel synthesis, electrochemical deposition, hydrothermal synthesis and anodization. However, a universally accepted synthesis method for this material is not offered. The most appropriate method and its corresponding processing parameters for the synthesis of nano tungsten oxide dihydrate colloids were presented in the present study. The objective of the present study was to investigate the effect of processing parameters, i.e. applied voltage, temperature and anodizing duration on the particle size of nanocolloids. It is found that anodization is the easiest, efficient, and cost-effective method to synthesize the colloidal solution of nano tungsten oxide dihydrate. Conducting the synthesis at room temperature at a voltage of 50 V for 60 minutes yields the product with particle size of 40 – 60 nm, which can be used in wide array of applications. This paper also highlights the research gaps for future work and gives recommendations to extend this study particularly for the industrial application of tungsten oxide.

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Synthesis of Hydroxyapatite and ZnO Nanoparticles via Different Routes and its Comparative Analysis

Material Science Research India ◽

10.13005/msri/130102 ◽

2016 ◽

Vol 13 (1) ◽

pp. 07-13 ◽

Cited By ~ 2

Author(s):

P. Mahapatra ◽

Shreya Kumari ◽

Simran Simran ◽

Shruti Sharma ◽

K. Gaurav ◽

...

Keyword(s):

Particle Size ◽

Acetic Acid ◽

Comparative Analysis ◽

Sol Gel ◽

Synthesis Methods ◽

X Ray Diffraction ◽

X Ray ◽

Wurtzite Crystal Structure ◽

Egg Shells ◽

Removal Of Metal Ions

Hydroxyapatite (HAp) was prepared from egg shells by various routes using hexane and acetic acid followed by heat treatment. HAp has a wide application in water treatment by removal of metal ions. XRD of the samples showed use of acetic acid followed by high temperature sintering leads to formation crystalline phases of HAp. Strong evidence of CaCO3 in calcite phase was obtained in other samples. Zinc oxide nanoparticles have also been synthesized by different methods such as sol-gel, co- precipitate and green synthesis. The effect of different synthesis methods were investigated using X-Ray Diffraction (XRD). The structural properties of nanoparticles including particle size were calculated from XRD data. The XRD reveals that the prepared ZnO samples were highly crystalline, having wurtzite crystal structure. The comparative analysis shows variations in particle size with different synthesis methods.

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The Influence of Surfactants on Crystallization of Nanocrystalline HZSM-5 Zeolite

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.423-426.117 ◽

2013 ◽

Vol 423-426 ◽

pp. 117-120

Author(s):

Jun Fang Wei ◽

Fang Zhu ◽

Xiao Yan Zhang

Keyword(s):

Particle Size ◽

Hydrothermal Synthesis ◽

Anionic Surfactant ◽

Average Particle Size ◽

Synthesis Method ◽

Average Particle ◽

X Ray Diffraction ◽

Scanning Electronic Microscopy ◽

Electronic Microscopy ◽

X Ray

With addition of surfactants, a nanocrystalline HZSM-5 zeolite was prepared by hydrothermal synthesis method. X-ray diffraction (XRD) characterization results showed that surfactants can constraint the crystallization of HZSM-5. Scanning electronic microscopy (SEM) characterization revealed that nanocrystalline HZSM-5 with more regular morphology and smaller particle size can be prepared with suitable surfactants as additives. The HZSM-5 particles were 200-800 nm in size and constructed by primary HZSM-5 nanocrystals of 3050 nm. The average particle size will grow up to 800 nm with a cationic surfactant, and decrease to 200 nm with a anionic surfactant.

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DETERMINATION OF THE SIZES OF PARTICLES OF SUPERCONDUCTING CUPRATE Y3Ba5Cu8OX BY MEANS OF DIFFERENT METHODS

Technology Transfer fundamental principles and innovative technical solutions ◽

10.21303/2585-6847.2020.001504 ◽

2020 ◽

Vol 4 ◽

pp. 10-13

Author(s):

Anastasiia Bolotnikova

Keyword(s):

Particle Size ◽

Size Structure ◽

Solid Phase ◽

Sol Gel ◽

Synthesis Method ◽

Precipitation Method ◽

Phase Method ◽

Synthesis Methods ◽

Scherrer Formula ◽

Co Precipitation

The superconducting cuprate Y3Ba5Cu8Ox was obtained with the help of sol-gel technology (sample C), co-precipitation of hydroxocarbonates (sample B) and solid-phase synthesis methods (A). Based on the results of scanning electron microscopy and methods based on the analysis of X-ray diffraction data: the Williamson-Hall construction and the Scherrer formula, features of the microstructure of the synthesized samples are established. The smallest particle size has a sample that has been synthesized by the sol-gel method. The tendency to aggregation and sedimentation for this sample is the smallest. The sample obtained by the co-precipitation method has larger grains and a higher tendency to aggregate. The size of the microparticles and the tendency to aggregate for the sample synthesized by the solid-phase method are greatest. The morphology of particles was studied using three methods: SEM, Scherrer and Williamson-Hall formulas and the following results were found: particle size depends on the synthesis method, but a relatively narrow size distribution within one synthesis method remains, the value of crystal lattice microdeformation for samples increases in a line: C sample– A sample– B sample. Thus, the work was carried out for determining the size, structure and morphology of superconducting phases. It expands knowledge in the field of research of superconducting compounds

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Effect of Synthesis Method on the Nanostructures of Magnesium Oxide (MgO) and their Band Gap Energies

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.545.153 ◽

2012 ◽

Vol 545 ◽

pp. 153-156 ◽

Cited By ~ 2

Author(s):

Nor Fadilah Chayed ◽

Nurhanna Badar ◽

Rusdi Roshidah ◽

Norashikin Kamarudin ◽

Norlida Kamarulzaman

Keyword(s):

Electron Microscopy ◽

Band Gap ◽

Magnesium Oxide ◽

Sol Gel ◽

Synthesis Method ◽

Nir Spectroscopy ◽

Synthesis Methods ◽

X Ray Diffraction ◽

X Ray ◽

Scanning Electron

Magnesium oxide (MgO) is a metal oxide which has many applications in industry and can be synthesized by many different synthesis methods. In this study, MgO was synthesized by using two different methods which were sol-gel and solid-state reaction methods. Both samples were annealed at 800 oC for 24 hours and characterized by using X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). The band gap energies for both samples were determined by using UV-Vis NIR Spectroscopy. The band gap values of the samples are evaluated from the data. It was found that the band gap energies of the MgO using different synthesis route were not the same.

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Aqueous Sol-Gel Synthesis of Different Iron Ferrites: From 3D to 2D

Materials ◽

10.3390/ma14061554 ◽

2021 ◽

Vol 14 (6) ◽

pp. 1554

Author(s):

Justinas Januskevicius ◽

Zivile Stankeviciute ◽

Dalis Baltrunas ◽

Kęstutis Mažeika ◽

Aldona Beganskiene ◽

...

Keyword(s):

Magnetic Measurements ◽

Substrate Surface ◽

Sol Gel ◽

Synthesis Method ◽

Xrd Analysis ◽

Dip Coating ◽

Yttrium Iron ◽

Iron Garnet ◽

Dip Coating Technique ◽

Sol Gel Synthesis

In this study, an aqueous sol-gel synthesis method and subsequent dip-coating technique were applied for the preparation of yttrium iron garnet (YIG), yttrium iron perovskite (YIP), and terbium iron perovskite (TIP) bulk and thin films. The monophasic highly crystalline different iron ferrite powders have been synthesized using this simple aqueous sol-gel process displaying the suitability of the method. In the next step, the same sol-gel solution was used for the fabrication of coatings on monocrystalline silicon (100) using a dip-coating procedure. This resulted, likely due to substrate surface influence, in all coatings having mixed phases of both garnet and perovskite. Thermogravimetric (TG) analysis of the precursor gels was carried out. All the samples were investigated by X-ray powder diffraction (XRD) analysis. The coatings were also investigated by scanning electron microscopy (SEM), atomic force microscopy (AFM) and Mössbauer spectroscopy. Magnetic measurements were also carried out.

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Green synthesis and characterization of hexaferrite strontium-perovskite strontium photocatalyst nanocomposites

Main Group Metal Chemistry ◽

10.1515/mgmc-2020-0004 ◽

2020 ◽

Vol 43 (1) ◽

pp. 26-42 ◽

Cited By ~ 2

Author(s):

Zahra Hajian Karahroudi ◽

Kambiz Hedayati ◽

Mojtaba Goodarzi

Keyword(s):

Magnetic Properties ◽

Green Synthesis ◽

Sol Gel ◽

Synthesis Method ◽

Combustion Method ◽

Lemon Juice ◽

X Ray Diffraction ◽

X Ray ◽

Auto Combustion

AbstractThis study presents a preparation of SrFe12O19– SrTiO3 nanocomposite synthesis via the green auto-combustion method. At first, SrFe12O19 nanoparticles were synthesized as a core and then, SrTiO3 nanoparticles were prepared as a shell for it to manufacture SrFe12O19–SrTiO3 nanocomposite. A novel sol-gel auto-combustion green synthesis method has been used with lemon juice as a capping agent. The prepared SrFe12O19–SrTiO3 nanocomposites were characterized by using several techniques to characterize their structural, morphological and magnetic properties. The crystal structures of the nanocomposite were investigated via X-ray diffraction (XRD). The morphology of SrFe12O19– SrTiO3 nanocomposite was studied by using a scanning electron microscope (SEM). The elemental composition of the materials was analyzed by an energy-dispersive X-ray (EDX). Magnetic properties and hysteresis loop of nanopowder were characterized via vibrating sample magnetometer (VSM) in the room temperature. Fourier transform infrared spectroscopy (FTIR) spectra of the samples showed the molecular bands of nanoparticles. Also, the photocatalytic behavior of nanocomposites has been checked by the degradation of azo dyes under irradiation of ultraviolet light.

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Semi sol-gel synthesis and red luminescence studies of Eu3+ activated Double perovskite phosphors Bi2-xEuxMoO6 (x=0.0–0.24)

Optik ◽

10.1016/j.ijleo.2019.01.086 ◽

2019 ◽

Vol 182 ◽

pp. 565-570 ◽

Cited By ~ 1

Author(s):

B. Nagamani Naidu ◽

K. Koteswara Rao ◽

M.P.S. Murali Krishna

Keyword(s):

Sol Gel ◽

Double Perovskite ◽

Red Luminescence ◽

Sol Gel Synthesis

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Microwave-Assisted vs. Conventional Hydrothermal Synthesis of MoS2 Nanosheets: Application towards Hydrogen Evolution Reaction

Crystals ◽

10.3390/cryst10111040 ◽

2020 ◽

Vol 10 (11) ◽

pp. 1040 ◽

Cited By ~ 1

Author(s):

Getachew Solomon ◽

Raffaello Mazzaro ◽

Vittorio Morandi ◽

Isabella Concina ◽

Alberto Vomiero

Keyword(s):

Hydrothermal Synthesis ◽

Hydrothermal Method ◽

Hydrogen Evolution ◽

Hydrogen Evolution Reaction ◽

Current Density ◽

Crystal Morphology ◽

Synthesis Method ◽

Synthesis Methods ◽

Mos2 Nanosheets ◽

Microwave Assisted

Molybdenum sulfide (MoS2) has emerged as a promising catalyst for hydrogen evolution applications. The synthesis method mainly employed is a conventional hydrothermal method. This method requires a longer time compared to other methods such as microwave synthesis methods. There is a lack of comparison of the two synthesis methods in terms of crystal morphology and its electrochemical activities. In this work, MoS2 nanosheets are synthesized using both hydrothermal (HT-MoS2) and advanced microwave methods (MW-MoS2), their crystal morphology, and catalytical efficiency towards hydrogen evolution reaction (HER) were compared. MoS2 nanosheet is obtained using microwave-assisted synthesis in a very short time (30 min) compared to the 24 h hydrothermal synthesis method. Both methods produce thin and aggregated nanosheets. However, the nanosheets synthesized by the microwave method have a less crumpled structure and smoother edges compared to the hydrothermal method. The as-prepared nanosheets are tested and used as a catalyst for hydrogen evolution results in nearly similar electrocatalytic performance. Experimental results showed that: HT-MoS2 displays a current density of 10 mA/cm2 at overpotential (−280 mV) compared to MW-MoS2 which requires −320 mV to produce a similar current density, suggesting that the HT-MoS2 more active towards hydrogen evolutions reaction.

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Nanostructured TiO2-Based Composites for Light Absorption

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.975.207 ◽

2014 ◽

Vol 975 ◽

pp. 207-212

Author(s):

Dayse I. dos Santos ◽

Olayr Modesto Jr. ◽

Luis Vicente A. Scalvi ◽

Americo S. Tabata

Keyword(s):

Metal Oxide ◽

Light Absorption ◽

Structural Characteristics ◽

Sol Gel ◽

Second Phase ◽

X Ray Diffraction ◽

Two Phase ◽

X Ray ◽

Oxide Powders

Metal oxide nanocomposites were prepared by two different routes: polyol and sol-gel. Characterization by X ray diffraction showed that the first process produces directly a two-phase material, while the sol-gel powder never showed second phase below 600°C. Light spectroscopy of the treated powders indicated similarities for the processed materials. Although the overall material compositions are about the same, different structural characteristics are found for each processing. With the exception of Ti-Zn materials, all the double metal oxide powders showed higher absorbance than either TiO2 powder.

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