Preparation and Dielectric Property of BaTiO3 Nanoparticles by Salt-Assisted Spray Pyrolysis

2013 ◽  
Vol 566 ◽  
pp. 281-284
Author(s):  
Nobutaka Shimizu ◽  
Kenichi Myoujin ◽  
Takayuki Kodera ◽  
Takashi Ogihara
Keyword(s):  
Dielectric Constant ◽  
Relative Density ◽  
Spray Pyrolysis ◽  
Particle Distribution ◽  
Average Particle Size ◽  
Relative Dielectric Constant ◽  
Sintered Body ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Average Size

BaTiO3 nanopowders were prepared by salt-assisted spray pyrolysis using a flux of KNO3 and NaNO3. Compounds of metal sources are thermally decomposed in the melting flux. Some flux mixtures make a eutectic composition because of the reduced melting point of the flux. The optimum temperature for the preparation of BaTiO3 nanoparticles was 700 °C. When both KNO3 and NaNO3 were used as the flux, the average particle size of the BaTiO3 powders was 40 nm, and the particle distribution was broad. On the other hand, when only KNO3 was used, the average size of BaTiO3 powders was 60 nm, and the particle distribution was narrow. This suggested that the sodium ions in the BaTiO3 nanoparticles led to a broad particle distribution. X-ray diffraction (XRD) revealed that all the diffraction peaks were in agreement with the crystal phase of BaTiO3. The relative density of the sintered body of BaTiO3 powders was 87 %. The relative dielectric constant of the sintered body was 1180, and the dielectric loss (tanδ) was 0.023 at room temperature. This suggested that the residual potassium ions in the BaTiO3 nanoparticles led to a reduction in the relative density and dielectric constant.

scholarly journals Synthesis of MgO Nanoparticles by Solvent Mixed Spray Pyrolysis Technique for Optical Investigation

2014 ◽  
Vol 2014 ◽  
pp. 1-4 ◽  
Author(s):  
K. R. Nemade ◽  
S. A. Waghuley
Keyword(s):  
Particle Size ◽  
Spray Pyrolysis ◽  
Spray Pyrolysis Technique ◽  
Average Particle Size ◽  
Band Gap Energy ◽  
Average Particle ◽  
Optical Investigation ◽  
X Ray Diffraction ◽  
Mgo Nanoparticles ◽  
Electron Microscope Analysis

Solvent mixed spray pyrolysis technique has attracted a global interest in the synthesis of nanomaterials since reactions can be run in liquid state without further heating. Magnesium oxide (MgO) is a category of the practical semiconductor metal oxides, which is extensively used as catalyst and optical material. In the present study, MgO nanoparticles were successfully synthesized using a solvent mixed spray pyrolysis. The X-ray diffraction pattern confirmed the formation of MgO phase with an excellent crystalline structure. Debye-Scherrer equation is used for the determination of particle size, which was found to be 9.2 nm. Tunneling electron microscope analysis indicated that the as-synthesized particles are nanoparticles with an average particle size of 9 nm. Meanwhile, the ultraviolet-visible spectroscopy of the resulting product was evaluated to study its optical property via measurement of the band gap energy value.

Preparation and Characterization of Gold Nanoparticles in the Presence of Citrate and Soybean Seed Extract in an Acidic Conditions

Drug Research ◽  
2017 ◽  
Vol 67 (05) ◽  
pp. 266-270 ◽  
Author(s):  
Ebrahim Izadi ◽  
Ali Rasooli ◽  
Abolfazl Akbarzadeh ◽  
Soodabeh Davaran
Keyword(s):  
Particle Size ◽  
Gold Nanoparticles ◽  
Size Distribution ◽  
Average Particle Size ◽  
Soybean Seed ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Soybean Extract ◽  
Average Size

AbstractThrough the present study, an eco-friendly method was used to synthesize the gold nanoparticles (GNPs) by using the sodium citrate and extract of the soybean seed as reducing the agents at PH 3. X-Ray diffraction (XRD) method was used to evaluate the crystal structure of as-synthesized NPs and it’s revealed that this method leads to well crystallized GNPs. In order to determine the particle size and their distribution, field emission scanning microscopy (FE-SEM) and dynamic light scattering (DLS) were used. The results showed that, the average particle size distribution of synthesized GNPs in solutions containing of the soybean extract and 1% citrate at PH 3 is about 109.6 and 140.9 nm, respectively. Also, we find that the average size of GNPs is 40 and 33 nm from solutions of citrate and soybean extract, respectively. It was concluded that using the extract of soybean seeds as reducing agent can lead to GNPs with small size and narrow size distribution.

Fabrication of Nano-Sized Tin Oxide Powder by Spray Pyrolysis Process

2009 ◽  
Vol 1174 ◽  
Author(s):  
Jaekeun Yu ◽  
Jwayeon Kim ◽  
Jeoungsu Han
Keyword(s):  
Particle Size ◽  
Spray Pyrolysis ◽  
Reaction Temperature ◽  
Tin Oxide ◽  
Average Particle Size ◽  
Raw Material ◽  
Nano Particles ◽  
Average Particle ◽  
Average Size ◽  
20 Nm

AbstractBy using tin chloride solution as the raw material, a nano-sized tin oxide powder with average particle size below 50 nm is generated by spray pyrolysis reaction. This study also examines the influences of the reaction parameters such as reaction temperature and the concentration of raw material solution on the powder properties. As the reaction temperature increases from 800 to 850 ℃, the average particle size of the generated powder increases from 20 nm to 30 nm. As the reaction temperature reaches 900 ℃, the droplets are composed of nano-particles with average size of 30 nm, while the average size of individual particles increases remarkably up to 80˜100 nm. When the tin concentration reaches 75 g/L, the average particle size of the powder is below 20 nm. When the tin concentration reaches 150 g/L, the droplets are composed of nano particles with average size around 30 nm, whereas the average size of independent particles increases up to 80˜100 nm. When the concentration reaches 400 g/L, the droplets are composed of nano-particles with average size of 30 nm.

scholarly journals Preparation and characterization of graphene nanosheet doped with silver nanoparticles

2021 ◽  
Vol 2063 (1) ◽  
pp. 012012
Author(s):  
A H Mohammed ◽  
A N Naje
Keyword(s):  
Graphene Sheet ◽  
Average Particle Size ◽  
Wide Band ◽  
Peak Position ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Force Microscopy ◽  
Atomic Force ◽  
Band Absorption ◽  
Average Size

Abstract Simple process (exploding wire technique) was used to Prepared sliver nanoparticles (AgNPs). The graphene sheet was added to AgNPs with different concentrations (0.002g/ml and 0.01g/ml). well dispersion of AgNPs are achieved by simple chemistry process. The samples were characterized by ultraviolet-visible spectroscopy (UV-Vis), x-ray diffraction (XRD), atomic force microscopy (AFM) and Field emission scanning electron microscope (FESEM). The results showed a wide band absorption of AgNPs-graphene (AgNPs-GN) extended from VU to IR region, surface plasmon resonance (SPR) absorption peak position for the AgNPs at (350-600) nm, XRD confirmed the clear distribution of the peaks attributed to polycrystalline for AgNPs appeared at 20=38.14°, 44.27°, 64.33, and 77.37° respectively and AgNPs-GN at 2θ=26.51° and 54.65°. The AFM showed that AgNPs have uniformly distribution on the surface of graphene sheet. The average size of AgNPs was confirmed by around (50-80) nm by FESEM and the AgNPs-GN have average particle size (20-40) nm. The AgNPs-GN could become prominent candidate for optoelectronic applications.

Synthesis and Characterization of Samarium Doped Ceria(Ce0.8Sm0.2O1.9) Nano-Particle by Aerosol Plasma Pyrolysis

2009 ◽  
Vol 421-422 ◽  
pp. 490-493
Author(s):  
Kenichi Myoujin ◽  
Yoshiki Ichikawa ◽  
Araki Toriyama ◽  
Takayuki Kodera ◽  
Takashi Ogihara
Keyword(s):  
Particle Size ◽  
Relative Density ◽  
Average Particle Size ◽  
Metal Nitrate ◽  
Average Particle ◽  
Starting Solution ◽  
Bet Analysis ◽  
Plasma Pyrolysis ◽  
Average Size ◽  
Precursor Powders

Spherical Ce0.8Sm0.2O1.9 precursor powders were synthesized by Aerosol Plasma pyrolysis using aqueous solution of metal nitrate. As-prepared powders obtained by this method have a spherical morphology with a nano size and submicron size. They had bimodal size distribution. The average size of primary particles was less than 100 nm. The concentrations of starting solution influenced to average particle size. The relative density of SDC pellet was highest when it was sintered at 1623 K. The relative density was 86 %. XRD, SEM, DTA-TG and BET analysis were used for determination of the composition, morphology, particle size and surface area.

COMPARATIVE STUDY OF DIELECTRIC BEHAVIOR OF Mn0.4Zn0.6Fe2O4 NANOFERRITE BY CITRATE PRECURSOR METHOD

2008 ◽  
Vol 22 (16) ◽  
pp. 2537-2544 ◽  
Author(s):  
PREETI MATHUR ◽  
ATUL THAKUR ◽  
M. SINGH
Keyword(s):  
Particle Size ◽  
Dielectric Constant ◽  
Comparative Study ◽  
Average Particle Size ◽  
Dielectric Behavior ◽  
Average Particle ◽  
Oxidizing Agent ◽  
Precursor Method ◽  
Citrate Precursor ◽  
Citrate Precursor Method

In the present work, comparative study of the dielectric behavior of Mn 0.4 Zn 0.6 Fe 2 O 4 ferrite synthesized with and without H 2 O 2 (hydrogen peroxide) has been presented. The dc resistivity has been improved by the citrate precursor method as compared to the ceramic method, and it is further improved by the addition of H 2 O 2, which acts as a strong oxidizing agent. We have shown by means of X-ray diffraction that the resulting ferrite is made up of nanocrystallites and the average size of these nanocrystallites–calculated by Scherrer's formula–depends on the polarizer. The average particle size was found to be ~70 nm with H 2 O 2 and ~88 nm without H 2 O 2. The particle size is further confirmed by scanning electron microscopy. Both the results are found to be in good agreement. The decrease in dielectric constant and dielectric loss factor by addition of oxidizing agent is justified by inverse proportionality between the resistivity and dielectric constant. Possible mechanisms contributing to these processes have been discussed.

scholarly journals Thermal, Structural, and Physical Properties of Freeze Dried Tropical Fruit Powder

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
K. A. Athmaselvi ◽  
C. Kumar ◽  
M. Balasubramanian ◽  
Ishita Roy
Keyword(s):  
Particle Size ◽  
Physical Properties ◽  
Average Particle Size ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Tropical Fruit ◽  
X Ray ◽  
Freeze Dried ◽  
Fruit Powder ◽  
Lcr Meter

This study evaluates the physical properties of freeze dried tropical (guava, sapota, and papaya) fruit powders. Thermal stability and weight loss were evaluated using TGA-DSC and IR, which showed pectin as the main solid constituent. LCR meter measured electrical conductivity, dielectric constant, and dielectric loss factor. Functional groups assessed by FTIR showed presence of chlorides, and O–H and N–H bonds in guava, chloride and C–H bond in papaya, and chlorides, and C=O and C–H bonds in sapota. Particle size and type of starch were evaluated by X-ray diffraction and microstructure through scanning electronic microscopy. A semicrystalline profile and average particle size of the fruit powders were evidenced by X-ray diffraction and lamellar/spherical morphologies by SEM. Presence of A-type starch was observed in all three fruits. Dependence of electric and dielectric properties on frequency and temperature was observed.

Samanea saman: A Novel Mucoadhesive Gum

2021 ◽  
pp. 57-62
Author(s):  
Nayana S. Baste ◽  
Ganesh. D. Basarkar
Keyword(s):  
Stress Measurement ◽  
Average Particle Size ◽  
Physicochemical Characterization ◽  
Qualitative Evaluation ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Natural Polymers ◽  
Chemical Evaluation ◽  
Research Article ◽  
Samanea Saman

Natural polymers are the most accepted pharmaceutical excipients of formulator’s choice. The reasons for this are their cost effectiveness, biocompatibility and availability. In this research article natural gum was extracted from the seeds of Samanea saman by using ethanol as a solvent. The physicochemical characterization like Loss on drying, Total ash and Acid insoluble ash, Swelling Index, Viscosity and qualitative evaluation of purified gum was done. The percent yield of gum was found to 6% w/w and the swelling index was found to be 18.5. Total ash value (7.5% w/w) and Acid insoluble ash value (1.4%w/w) shows purity of gum whereas 3.2% w/w loss on drying suggest low moisture content of gum. Chemical evaluation shows presence of carbohydrate. X ray diffraction graph of gum shows crystalline nature. The gum has average particle size 45.0±0.32 to 50±0.18μm, and the surface texture of the particles was found to be rough and irregular by scanning Electron Microscopy. Mucoadhesive property of gum was evaluated by Swelling index, Mucoadhesive force, Shear stress measurement. For this study polymeric tablet of gum with concentrations like 10%, 30%, 50%, 70% and 90 %w/w were formulated and the results shows best mucoadhesive and swelling property. From the above result the gum may be used in the formulation of mucoadhesive dosage form.

scholarly journals Hydrothermal synthesis of tetragonal barium titanate nanopowders under moderate conditions

2021 ◽  
Vol 15 (2) ◽  
pp. 179-183
Author(s):  
Huaxing Meng ◽  
Zhiwu Chen ◽  
Zhenya Lu ◽  
Xin Wang ◽  
Xiaoyi Fu
Keyword(s):  
Barium Titanate ◽  
Average Particle Size ◽  
Ammonia Solution ◽  
Average Particle ◽  
Titanium Hydroxide ◽  
X Ray Diffraction ◽  
Hydrothermal Route ◽  
Uniform Size ◽  
Dominant Structure ◽  
Hydrolysis Of

Monodispersed tetragonal barium titanate (BaTiO3) nanopowders were synthesized by a convenient hydrothermal route at a low temperature of 200?C in only 24 h. The key point of this method is to promote the generation of ultrafine titanium hydroxide precipitation precursors with the help of absolute ethyl alcohol and ammonia solution during the hydrolysis of Ti(OC4H9)4. The results of X-ray diffraction and Raman spectra show that the as-prepared BaTiO3 nanopowders possess tetragonal-dominant structure. The synthesized tetragonal BaTiO3 nanopowders exhibit relatively uniform size and good dispersity, with the average particle size of 96.1 nm and a tetragonality of 1.0073, which enable broad application prospects in the field of multilayer ceramic capacitors.

Preparation and Magnetic Properties of Carbon Encapsulated Fe-Cu Alloy Nanoparticles

2010 ◽  
Vol 177 ◽  
pp. 673-676 ◽  
Author(s):  
Jun Xue ◽  
Hou Kui Xiang ◽  
Hong Qiao Ding ◽  
Shu Li Pang ◽  
Xue Hua Wang ◽  
...  
Keyword(s):  
Magnetic Measurement ◽  
Average Particle Size ◽  
Soft Magnetic Property ◽  
Copper Nitrate ◽  
Synthesis Process ◽  
Ferric Nitrate ◽  
Average Particle ◽  
X Ray Diffraction ◽  
X Ray ◽  
Cu Alloy

Carbon encapsulated Fe-Cu alloys nanoparticles were synthesized by using ferric nitrate, copper nitrate as metal sources and using sucrose as carbon source. The synthesis process involved a step of hydrazine hydrate reduction in alcohol solution and a step of annealing carbonization. The as-prepared samples were characterized by X-ray diffraction technique, X-ray energy dispersion spectrograph, trans- mission electron microscopy and Raman spectroscopy. The results showed the sample was core / shell structure, the metalic core was crystalline FeCu4 alloy, the shell was amorphous carbon, and the average particle size was about 51nm. The magnetic measurement by using a vibrating sample magnetometer revealed that the sample has ultra-soft magnetic property with the saturation magnetization Ms of 13.01 emu/g, residual magnetization Mr of 0.37 emu/g and coercive forces Hc of 54.43 Oe at room temperature.

Sign in / Sign up

Export Citation Format

Share Document