scholarly journals CARBONATE PRECURSOR ROUTE FOR PREPARATION OF CaCu3Ti4O12

2021 ◽  
Vol 87 (7) ◽  
pp. 47-60
Author(s):  
Oleg Yanchevskii ◽  
Oleg V'yunov ◽  
Tetiana Plutenko
Keyword(s):  
Synthesis Method ◽  
Ccto Ceramic ◽  
Precipitation Method ◽  
Dielectric Losses ◽  
Carbonate Precipitation ◽  
Frequency Range ◽  
Precursor Route ◽  
Tan Δ ◽  
Co Precipitation ◽  
Carbonate Precursor

A simple CaCu3Ti4O12 synthesis method by carbonate precipitation has been developed, which is not inferior to the known methods of precipitation from solutions. The optimum temperatures for the synthesis of powder (850 оС) and sintering of ceramics (1080 оС) have been found. The CCTO ceramic prepared has stable and fine electrical properties. In the frequency range of 1 kHz to 1 MHz, the ε’ value always is higher 104 with the dielectric losses, tan δ ~ 0.05–0.08. Such CCTO ceramic prepared by the сarbonate co-precipitation method with good electric properties should find applications in electric devices.

Effect of the Synthesis Method on the Properties of Ultrafine YAG Powder

2018 ◽  
Vol 281 ◽  
pp. 40-45
Author(s):  
Jie Guang Song ◽  
Lin Chen ◽  
Cai Liang Pang ◽  
Jia Zhang ◽  
Xian Zhong Wang ◽  
...  
Keyword(s):  
Particle Size ◽  
Calcination Temperature ◽  
Hydrothermal Reaction ◽  
Synthesis Method ◽  
Particle Morphology ◽  
Precipitation Method ◽  
Molar Ratio ◽  
Synthesis Process ◽  
Powder Materials ◽  
Co Precipitation

YAG materials has a number of unique properties, the application is very extensive. In this paper, the superfine YAG powder materials were prepared by co-precipitation method and hydrothermal precipitation method. The influence of synthesis process on the morphology of the powder was investigated. The results showed that the precursor powder prepared via the co-precipitation method is mainly from amorphous to crystalline transition with the increasing calcination temperature, the precursor agglomeration is more serious, In the process of increasing the calcination temperature, the dispersibility of the roasted powder is greatly improved, which is favorable for the growth of the crystal grains, so that the particle size of the powder is gradually increased, the YAG precursor prepared by the co-precipitation method is transformed into YAG crystals, the phase transition occurs mainly between 900 and 1100°C. When the molar ratio of salt to alkali is Y3+: OH-=1: 8 via the hydrothermal reaction, the YAG particles with homogeneous morphology can be obtained. When the molar ratio of salt and alkali is increased continuously, the morphology of YAG particles is not obviously changed. The co-precipitation method is easy to control the particle size, the hydrothermal method is easy to control the particle morphology.

Synthesis of Y3Al5-xFexO12 Nanopowder by the Co-Precipitation Method: Influence of Precipitate Agent

2013 ◽  
Vol 341-342 ◽  
pp. 114-118
Author(s):  
Min Zeng ◽  
Yun Hong Wang
Keyword(s):  
Phase Formation ◽  
Formation Process ◽  
Raw Materials ◽  
Precipitation Method ◽  
Precipitation Technique ◽  
Pure Phase ◽  
Co Precipitation ◽  
Carbonate Precursor ◽  
Phase Formation Process

The Y3Al5-xFexO12 (0x5, YAIG) powders have been prepared by co-precipitation technique in which NH4HCO3 or (NH4)2CO3 is used as a precipitant and Y(NO3)3·6H2O, Al (NO3)3·9H2O and Fe (NO3)3·9H2O as raw materials. The composition of YAIG precursor, the phase formation process of YAIG and the properties of the powders were investigated by means of XRD, SEM, TEM and EDS. The results indicated that the precipitant effects the preparation of pure-phase YAIG powders. AC as precipitant could produce a hydroxide precursor, which transformed to a mixture. AHC as precipitant could produce a loosely agglomerated carbonate precursor. The resultant YAIG powders showed good dispersity and excellent sinterability.

scholarly journals Synthesis and Characterization of TiO2 Nanoparticles for Solar Cell Applications

2019 ◽  
Vol 8 (9) ◽  
pp. 2462-2465
Keyword(s):  
Solar Cell ◽  
Tio2 Nanoparticles ◽  
Sol Gel ◽  
Synthesis Method ◽  
Pollutant Removal ◽  
Precipitation Method ◽  
Micro Particles ◽  
Wide Range ◽  
Titanium Tetra Isopropoxide ◽  
Co Precipitation

Titanium dioxide (TiO2 ) nanoparticles were synthesized using three different approaches successfully. These approaches were adopted as per different applications of TiO2 nanoparticles. These samples were characterized using X- ray diffraction (XRD) technique. XRD revealed nanocrystalline regime of TiO2 nanoparticles in each approach. The calculated size of nanoparticle was less than 11 nm in the used chemical approaches. Prominent and broad peaks were observed in XRD pattern for all samples, which showed all samples were in nanocrytalline form. The particle size was calculated for first three most intense prominent XRD peaks. By adopting sol gel method using Titanium tetra isopropoxide (TTIP) as precursor, the synthesized Titania particles were pure anatas and of size 7 to 11nm and using co-precipitation method using TiCl3 as precursor synthesized Titania were pure rutile and of size 3 to 7 nm. The co-precipitation method has been best suited for getting smaller nanoparticles. It was also observed that Solid state mechanical reduction root can be used to reduce the size of Titania micro-particles up to about 60 nm but phase of nanoparticles remains same as starting microparticles. It has been seen that the material properties of TiO2 can be tuned by proper method of synthesis. The work may play important role to choose particular synthesis method for specific application. These nano synthesized TiO2 materials may be used in a wide range of applications such as dye sensitized solar cell, photocatalysis, antibacterial, environment pollutant removal and photoactivated self cleaning properties etc

scholarly journals Recent progress in the shaping and sintering of barium titanate nanoparticles. Application to high permittivity capacitors

2012 ◽  
Vol 2012 (CICMT) ◽  
pp. 000222-000227
Author(s):  
Sophie Guillemet-Fritsch ◽  
Christophe Voisin ◽  
Roman Nava Quintero ◽  
Pascal Dufour ◽  
Christophe Tenailleau ◽  
...  
Keyword(s):  
Dielectric Properties ◽  
Barium Titanate ◽  
Tape Casting ◽  
Casting Process ◽  
Industrial Applications ◽  
The Other ◽  
Precipitation Method ◽  
Dielectric Losses ◽  
High Permittivity ◽  
Co Precipitation

The miniaturisation of electronic components required for many devices involves an increase their volumic efficiency. This work focus on the size reduction of capacitors. They are two ways for increasing the capacity of such passive components. One is to find materials with high permittivity, the other is to reduce the thickness of the films used in multilayers ceramics. Barium titanate, BaTiO3 (BT) nanoparticles were sintered using Spark Plasma Sintering (SPS) because the material presents interesting properties when obtained by SPS [1–3]. In this case, very unusual interesting dielectric properties, a so called “colossal” permittivity value up to several thousands. Moreover, no temperature dependence is observed. However, the values of dielectric losses are too high to consider industrial applications. In order to reduce these dielectric losses, different approaches have been proposed to control the chemistry of grain boundaries. We present here the structural, microstructural and electrical properties of ceramics sintered by SPS from BaTiO3 powders elaborated by co-precipitation method. Different routes tested to improve the dielectric properties of the ceramics are presented and discussed. On the other side, thick films of BT have been prepared. The objective of this work was to develop a BaTiO3 material having an accurate particle size to reduce the thickness of sintered films down to 1 μm. The rheological properties of the slurry have been optimized and, thanks to a suitable tape casting process, homogeneous thin films of 1 μm thickness could be obtained. Some properties of the films are described.

Preparation and Photocatalytic Performance of Flower-Shaped Zno/GO/Fe3O4 on Degradation of Rhodamine B

2021 ◽  
Vol 407 ◽  
pp. 161-172
Author(s):  
Mahbboobeh Rezaei ◽  
Ali Shokuhfar ◽  
Nikta Shahcheraghi
Keyword(s):  
Rhodamine B ◽  
Synthesis Method ◽  
Spectrophotometric Analysis ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
Photodegradation Efficiency ◽  
Time And Being ◽  
Co Precipitation ◽  
Uv C

In this work, a flower-shaped ZnO/GO/Fe3O4 ternary nanocomposite was synthesized via the co-precipitation method. Two significant goals of the study were boosting the degradation efficiency of ZnO and achieving a fast and simple synthesis approach. The structure, properties, and morphology of the product were characterized, and the effect of the ZnO flower-shaped structure in combination with GO nanosheets and magnetite nanoparticles was investigated on the photocatalytic activity. The structure and quality of the prepared nanocomposite were assessed by X-ray diffraction pattern, UV-visible DRS spectroscopy, Field Emission Scanning Electron Microscopy (FE-SEM). The catalytic activity of the nanocomposite was assessed by spectrophotometric analysis. The developed nanocomposite offered high photodegradation efficiency in Rhodamine B degradation under UV-C light in comparison with pure ZnO. At a specific period, the efficiency of the synthesized sample was about two times greater than that of pristine ZnO particles. Our nanocomposite is anticipated to have practical benefits in wastewater treatment given its good performance, economic savings through reducing the amount of catalyst consumption and saving time, and being a facile and fast synthesis method.

Influence of the Synthesis Method on the Microstructure and the Electronic Paramagnetic Resonance in Manganite of Eu0.05Ca0.95MnO3

2011 ◽  
Vol 691 ◽  
pp. 139-144 ◽  
Author(s):  
M. Santiago T. ◽  
H. Montiel ◽  
L.E. Hernández C. ◽  
G. Álvarez ◽  
Maricela Villanueva-Ibáñez ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Single Phase ◽  
Synthesis Method ◽  
Precipitation Method ◽  
Paramagnetic Resonance ◽  
Dc Magnetic Field ◽  
X Band ◽  
Preparation Route ◽  
Co Precipitation ◽  
Electron Paramagnetic

We present a comparison between co-precipitation method and polyol mediated synthesis for obtaining sub-micrometric powders of Eu0.05Ca0.95MnO3manganite. The samples synthesized were characterized by XRD and SEM; where the compounds have a single phase with the proposed stoichiometry. Microwave absorption response in poly-crystalline Eu0.05Ca0.95MnO3samples that it is carried out by both methods, are compared. These measurements were carried out at X-band (9.4 GHz) with a dc magnetic field up to 6000 Gauss, at 300 K. Electron Paramagnetic Resonance (EPR) spectra show important differences between both samples, indicating that the processes of magnetic absorption and the temperatures of phase transition are sensitive to order/disorder local; that we associate with the preparation route.

Effect of the synthesis method on the performance of Fe3O4–inositol hexaphosphate as a drug delivery vehicle for combination therapeutics with doxorubicin

2017 ◽  
Vol 41 (13) ◽  
pp. 5305-5312 ◽  
Author(s):  
Dandan Xu ◽  
Tongying Xu ◽  
Xuejie Guo ◽  
Qi Liu ◽  
Jingyuan Liu ◽  
...  
Keyword(s):  
Drug Delivery ◽  
Self Assembly ◽  
Solvothermal Synthesis ◽  
Synthesis Method ◽  
Precipitation Method ◽  
Layer By Layer ◽  
Delivery Vehicle ◽  
Inositol Hexaphosphate ◽  
One Step ◽  
Co Precipitation

Fe3O4–IP6 was fabricated via layer-by-layer electrostatic self-assembly following a solvothermal synthesis method and via a one-step co-precipitation method.

Preparation of Co0.5Zn0.5Fe2O4 and Co0.5Mn0.5Fe2O4 Nanoferrites by Co-Precipitation Method

2012 ◽  
Vol 620 ◽  
pp. 7-11
Author(s):  
Abdollah Javidan ◽  
Mir Hassan Hosseini ◽  
S.L. Shaifi
Keyword(s):  
Sodium Hydroxide ◽  
Zinc Ferrite ◽  
Room Temperature ◽  
Sem Analysis ◽  
Precipitation Method ◽  
Manganese Ferrite ◽  
Frequency Range ◽  
Calcination Process ◽  
Co Precipitation ◽  
Cobalt Zinc Ferrite

Nanoparticles of Cobalt-zinc ferrite (Co0.5Zn0.5Fe2O4) and Cobalt-manganese ferrite (Co0.5Mn0.5Fe2O4) have been synthesized at room temperature by co-precipitation method with and without calcination process. Starting materials for preparation of nanooxides were Co (NO3)2.6H2O, ZnCl2, Fe (NO3)3.9H2O and Mn (NO3)2.4H2O. These salats were mixed in stoichiometric amounts and precipitated with sodium hydroxide. Synthesised materials are confirmed by XRD and SEM analysis. The FTIR spectra of nanooxides have been analyzed in the frequency range of 400-4000cm-1.

Fabrication and Characterization of YAG Nanopowders by Co-Precipitation under Ultrasonic Radiation

2011 ◽  
Vol 284-286 ◽  
pp. 839-843 ◽  
Author(s):  
Li Li Wang ◽  
Jin Chen ◽  
Guang Cheng Yang ◽  
Fu De Nie
Keyword(s):  
Average Particle Size ◽  
Precipitation Method ◽  
Average Particle ◽  
Synthetic Process ◽  
Ultrasonic Radiation ◽  
Ft Ir ◽  
Fabrication And Characterization ◽  
Co Precipitation ◽  
Carbonate Precursor

A carbonate precursor with high sintering activity was prepared by co-precipitation method under ultrasonic radiation. This precursor precipitant completely transformed to pure YAG phase after being calcined at 900 °C for 4 h. The properties of YAG nanopowders obtained under different synthetic process were studied by XRD, TG-DSC, FT-IR and SEM. The results show that the ultrasonic radiation can fine the precursor and reduce its agglomeration. YAG nanopowders with an average particle size of about 60 nm were obtained and particles were sphere-shaped with good dispersity.

Microstructure and Dielectric Properties of BaFe12O19 Hexaferrite Nanoparticles: Effect of Cobalt Addition and Calcination Temperature

2020 ◽  
Vol 13 (3) ◽  
pp. 211-219
Keyword(s):  
Dielectric Properties ◽  
Barium Hexaferrite ◽  
Hexagonal Structure ◽  
Dielectric Constants ◽  
Precipitation Method ◽  
Calcination Temperatures ◽  
Transmission Electron ◽  
Tan Δ ◽  
Co Addition ◽  
Co Precipitation

Abstract: M-type Barium Hexaferrite (BaFe12O19) is a promising compound for technological applications because of its high permeability, high saturation magnetization and excellent dielectric properties. In this study, the microstructure and dielectric properties of CoxBaFe12O19Hexaferrite were investigated. The co-precipitation method was employed to prepare CoxBaFe12O19 nanoparticles, with x = 0, 0.04, 0.06 and 0.1 wt. %, at two different calcination temperatures (900oC and 950oC). The microstructure of the samples was examined through X-ray powder diffraction (XRD) and transmission electron microscopy (TEM). The hexagonal structure of the prepared samples was confirmed from XRD results. TEM images reveal the formation of agglomerated nanoparticles with different size distribution. The dielectric properties of the samples were studied through HIOKI 3532-50 LCR-Hi TESTER as a function of frequency (100 kHz–3MHz) and temperature (25 °C–500°C). The effects of Co addition, frequency and temperature on the dielectric constants (ɛʹ and ɛʹʹ), loss tangent (tan δ) and ac conductivity (σac) have been explained on the basis of hopping of electrons between Fe2+ and Fe3+ ions. Keywords: BaFe12O19 Hexaferrite, Co-precipitation method, XRD, Dielectric properties.

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