scholarly journals The Effects and Role of Polyvinylpyrrolidone on the Size and Phase Composition of Iron Oxide Nanoparticles Prepared by a Modified Sol-Gel Method

2017 ◽  
Vol 2017 ◽  
pp. 1-10 ◽  
Author(s):  
Marcela F. Silva ◽  
Luiz A. S. de Oliveira ◽  
Mariani A. Ciciliati ◽  
Michele K. Lima ◽  
Flávio F. Ivashita ◽  
...  
Keyword(s):  
Iron Oxide ◽  
Sol Gel ◽  
Average Crystallite Size ◽  
X Ray Diffraction ◽  
Transmission Microscopy ◽  
Gel Method ◽  
Sol Gel Method ◽  
Oxide Phases ◽  
Nuclear Environment

Fe2O3 nanoparticles (as maghemite and hematite mixtures) were prepared using adapted sol-gel method from a polyvinylpyrrolidone (PVP) aqueous solution in various Fe3+ : PVP monomer ratios. Analysis of X-ray diffraction was obtained to evaluate the crystalline state, average crystallite size, and composition of iron oxide phases. The morphology and average nanoparticles size were evaluated by electronic transmission microscopy. Magnetic properties of iron oxide were analyzed at low and room temperatures. Optical characteristics were evaluated by UV-Vis photoacoustic spectroscopy and the Mössbauer spectrum was obtained in order to evaluate subtle changes in the nuclear environment of the iron atoms.

Effect of Ni Substitution to Structure and Morphology of Ca0.9La0.05Bi0.05Mn1-xNixO3 by Sol-Gel Method

2020 ◽  
Vol 860 ◽  
pp. 117-121
Author(s):  
Mochammad Alfin Naufal Nur ◽  
Budhy Kurniawan
Keyword(s):  
Sol Gel ◽  
Average Crystallite Size ◽  
Morphological Properties ◽  
X Ray Diffraction ◽  
Gel Method ◽  
Sol Gel Method ◽  
Electrical And Magnetic Properties ◽  
Ni Content ◽  
Average Grain Size ◽  
Ni Substitution

The polycrystalline Ca0.9La0.05Bi0.05Mn1-xNixO3 (x = 0.025, 0.05, 0.075) samples were synthesized by sol-gel method. All samples were calcined at 650°C for 8 hours and sintered at 900°C for 8 hours. The structural and morphological properties of the samples were measured by X-ray diffraction (XRD) and Scanning electron microscope (SEM). The rietveld refinement shows that all samples were having an orthorhombic structure with pnma space group despite having different Ni content. Furthermore, the average crystallite size decreases with Ni substituion. SEM result shows the average grain size decreases with increasing Ni substitution regardless of the same heat treatment. This result will affect other properties like electrical and magnetic properties.

Study of Titanium Dioxide Thin Film by Sol-Gel Method

2014 ◽  
Vol 925 ◽  
pp. 278-281 ◽  
Author(s):  
Sharipah Nadzirah ◽  
Uda Hashim ◽  
N. Malihah
Keyword(s):  
Thin Film ◽  
Titanium Dioxide ◽  
Spin Coating ◽  
Sol Gel ◽  
Average Crystallite Size ◽  
X Ray Diffraction ◽  
Gel Method ◽  
X Ray ◽  
Sol Gel Method

Titanium dioxide (TiO2) thin films based interdigitated electrodes (IDEs) have been synthesized using sol-gel method with hydrochloric acid (HCl) as catalyst. The prepared TiO2 solution has been deposited onto silicon dioxide (SiO2) substrates via spin-coating technique. Film was annealed at 500 °C and aluminium (Al) IDEs have been fabricated. Finally the X-ray diffraction (XRD) shows high intensity of both anatase and rutile peaks exist on 10 nm TiO2 thin film. Average crystallite size of the nanoparticles is seen to be 25 nm. UvVisible spectroscopic (UvVis) technique was used for the transmittance spectra characterization of the sample.

Synthesis of Titania Nanoparticles by Ultrasonic Assistant Sol-Gel Method and its Photocatalytic Properties

2014 ◽  
Vol 955-959 ◽  
pp. 66-69
Author(s):  
Qiong Yu Liu ◽  
Jun Ting Jiang
Keyword(s):  
Sol Gel ◽  
Average Crystallite Size ◽  
Photocatalytic Properties ◽  
Titania Nanoparticles ◽  
X Ray Diffraction ◽  
Sunlight Irradiation ◽  
Gel Method ◽  
X Ray ◽  
Sol Gel Method ◽  
Photocatalytic Activities

Titania nanoparticles were obtained by an ultrasonic assistant sol-gel method. The prepared titania nanoparticles were characterized by X-ray diffraction (XRD) and differential scanning calorimeter (DSC). The photocatalytic properties of the prepared titania were evaluated from the photodegradation of X-3B solution. The thermalanalysis results showed that the weight loss of prepared TiO2particles ends at about 500°C, and the appropriate condition of calcination was found to be 2 h at 500°C. The XRD results showed that anatase was the main phase of prepared TiO2nanoparticle, and the average crystallite size of the TiO2particles, calcined for 2 h at 500°C was calculated as 15.3 nm using the Scherrer equation. The results demonstrated that such nanoTiO2showed high photocatalytic activities for X-3B degradation, whether it is under UV irradiation or sunlight irradiation.

Impedance Spectroscopy Study of LiTaO3 Powder Synthesized via Sol-Gel Method

2012 ◽  
Vol 545 ◽  
pp. 275-278 ◽  
Author(s):  
Lili Widarti Zainuddin ◽  
Norlida Kamarulzaman
Keyword(s):  
Room Temperature ◽  
Single Phase ◽  
Sol Gel ◽  
Rhombohedral Structure ◽  
Spectroscopy Study ◽  
X Ray Diffraction ◽  
Gel Method ◽  
X Ray ◽  
Sol Gel Method ◽  
Impedance Spectroscopy Study

A ceramics sample of LiTaO3 was prepared using a sol-gel method. The sample is annealed at 750 °C for 48 hours. X-ray diffraction analysis indicate the formation of single phase, rhombohedral structure. An ac impedance study was used to analyse the conductivity of LiTaO3 at room temperature and at various temperatures.

Magnetic Properties of Bulk Zn0.95-XMnXFe0.05O2 Prepared by Sol-Gel Method and Subsequent Hot Pressing

2011 ◽  
Vol 268-270 ◽  
pp. 356-359 ◽  
Author(s):  
Wen Song Lin ◽  
C. H. Wen ◽  
Liang He
Keyword(s):  
Magnetic Properties ◽  
Photoelectron Spectroscopy ◽  
Raw Materials ◽  
Sol Gel ◽  
Secondary Phase ◽  
X Ray Diffraction ◽  
Gel Method ◽  
X Ray ◽  
Sol Gel Method ◽  
Doped Zno

Mn, Fe doped ZnO powders (Zn0.95-xMnxFe0.05O2, x≤0.05) were synthesized by an ameliorated sol-gel method, using Zn(CH3COO)2, Mn(CH3COO)2and FeCl2as the raw materials, with the addition of vitamin C as a kind of chemical reducer. The resulting powder was subsequently compacted under pressure of 10 MPa at the temperature of 873K in vacuum. The crystal structure and magnetic properties of Zn0.95-xMnxFe0.05O2powder and bulk samples have been investigated by X-ray diffraction (XRD) and vibrating sample magnetometer (VSM). X-ray photoelectron spectroscopy (XPS) was used to study chemical valence of manganese, iron and zinc in the samples. The x-ray diffraction (XRD) results showed that Zn0.95-xMnxFe0.05O (x≤0.05) samples were single phase with the ZnO-like wurtzite structure. No secondary phase was found in the XRD spectrum. X-ray photoelectron spectroscopy (XPS) showed that Fe and Mn existed in Zn0.95-xMnxFe0.05O2samples in Fe2+and Mn2+states. The results of VSM experiment proved the room temperature ferromagnetic properties (RTFP) of Mn, Fe co-doped ZnO samples.

Fast response acetone-sensing properties of SnO2 nanoparticles prepared by the sol-gel method

2021 ◽  
Vol 93 (3) ◽  
pp. 30401
Author(s):  
Jiaxing Wang ◽  
Hai Yu ◽  
Yong Zhang
Keyword(s):  
High Performance ◽  
Gas Sensing ◽  
Sno2 Nanoparticles ◽  
Sol Gel ◽  
Fast Response ◽  
X Ray Diffraction ◽  
Gel Method ◽  
Sol Gel Method ◽  
Short Recovery Time ◽  
Acetone Gas Detection

SnO2 nanoparticle architectures were successfully synthesized using a sol-gel method and developed for acetone gas detection. The morphology and structure of the particles were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The SnO2 nanoparticle architectures were configured as high-performance sensors to detect acetone and showed a very fast response time (<1 s), a short recovery time (10 s), good repeatability and high selectivity at a relatively low working temperature. Thus, SnO2 nanoparticles should be promising candidates for designing and fabricating acetone gas sensors with good gas sensing performance. The possible gas sensing mechanism is also presented.

scholarly journals Effect of Preheating Temperature on Synthesis of Pure BiFeO3 via Sol–Gel Method

Nanopages ◽  
2019 ◽  
pp. 1-11
Author(s):  
G. M. Taha ◽  
M. N. Rashed ◽  
M. S. El-Sadek ◽  
M. A. Moghazy
Keyword(s):  
Electron Microscope ◽  
Transmission Electron Microscope ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
Pure Bifeo3 ◽  
Gel Method ◽  
X Ray ◽  
Sol Gel Method ◽  
Transmission Electron ◽  
Preheating Temperature

Abstract BiFeO3 (BFO) nanopowder was synthesized in a pure form via a sol- gel method based on glycol gel reaction. Effect of drying and preheating temperature on preventing other phases was studied. Many parameters were studied as calcination temperature and time & stirring temperature as well. The prepared powder was characterized by X-Ray Diffraction of powder (XRD) and Transmission Electron Microscope (TEM). High pure BiFeO3 was obtained by preheated process at 400 °C for 0.5 h and calcination at 600 °C for 0.5 h without any impurities compared to dry at110 °C.

Effect of Synthesis Conditions on the Structure and Electrochemical Properties of LiNi1/2Mn1/2O2 by Sol Gel Method

2011 ◽  
Vol 399-401 ◽  
pp. 1447-1450
Author(s):  
Zhi Yong Yu ◽  
Han Xing Liu
Keyword(s):  
Electrochemical Properties ◽  
Sol Gel ◽  
Electrochemical Analysis ◽  
X Ray Diffraction ◽  
Capacity Fading ◽  
Gel Method ◽  
X Ray ◽  
Sol Gel Method ◽  
Synthesis Conditions ◽  
A Current

The layered LiNi1/2Mn1/2O2 cathode materials were synthesized by a sol gel method. The effects of calcination temperature and time on the structural and electrochemical properties of the LiNi1/2Mn1/2O2 were investigated. The prepared samples were characterized by X-ray diffraction (XRD) and electrochemical analysis. The results revealed that the layered LiNi1/2Mn1/2O2 material could be optimal synthesized at temperature of 900°C for 10h. The sample prepared under the above conditions has the highest initial discharge capacity of 151 mAh/g and showed no dramatic capacity fading during 20 cycles between 2.5-4.5V at a current rate of 20mA/g.

scholarly journals Magnetic PbFe12O19-TiO2 nanocomposites and their photocatalytic performance in the removal of toxic pollutants

2018 ◽  
Vol 41 (3-4) ◽  
pp. 53-62 ◽  
Author(s):  
Behnaz Lahijani ◽  
Kambiz Hedayati ◽  
Mojtaba Goodarzi
Keyword(s):  
Electron Microscopy ◽  
Photocatalytic Performance ◽  
Sol Gel ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
Gel Method ◽  
Sol Gel Method ◽  
Photocatalytic Effect ◽  
Transmission Electron ◽  
Ultraviolet Light Irradiation

Abstract In this work, the PbFe12O19 nanoparticles were prepared by the simple and optimized precipitation method with different organic surfactants and capping agents. In the next step, the TiO2 nanoparticles were synthesized using the sol-gel method. At the final step, the PbFe12O19-TiO2 nanocomposites were prepared via the sol-gel method. The effect of the precipitating agent on the morphology and particle size of the products was investigated. The prepared products were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and Fourier transform infrared spectroscopy. The results obtained by the vibrating sample magnetometer show the magnetic properties of the ferrite nanostructures. The photocatalytic effect of the PbFe12O19-TiO2 nanocomposite on the elimination of the azo dyes (acid black, acid violet and acid blue) under ultraviolet light irradiation was evaluated. The results indicate that the prepared nanocomposites have acceptable magnetic and photocatalytic performance.

scholarly journals The Influence of Annealing Temperature on the Structure and Magnetic Properties of Nanocrystalline BiFeO3 Prepared by Sol–Gel Method

2021 ◽  
Author(s):  
T. Pikula ◽  
T. Szumiata ◽  
K. Siedliska ◽  
V. I. Mitsiuk ◽  
R. Panek ◽  
...  
Keyword(s):  
Grain Size ◽  
Magnetic Properties ◽  
Annealing Temperature ◽  
Sol Gel ◽  
Weak Ferromagnetism ◽  
X Ray Diffraction ◽  
Gel Method ◽  
Sol Gel Method ◽  
Average Grain Size ◽  
Spin Cycloid

AbstractIn this work, BiFeO3 powders were synthesized by a sol–gel method. The influence of annealing temperature on the structure and magnetic properties of the samples has been discussed. X-ray diffraction studies showed that the purest phase was formed in the temperature range of 400 °C to 550 °C and the samples annealed at a temperature below 550 °C were of nanocrystalline character. Mössbauer spectroscopy and magnetization measurements were used as complementary methods to investigate the magnetic state of the samples. In particular, the appearance of weak ferromagnetic properties, significant growth of magnetization, and spin-glass-like behavior were observed along with the drop of average grain size. Mössbauer spectra were fitted by the model assuming cycloidal modulation of spins arrangement and properties of the spin cycloid were determined and analyzed. Most importantly, it was proved that the spin cycloid does not disappear even in the case of the samples with a particle size well below the cycloid modulation period λ = 62 nm. Furthermore, the cycloid becomes more anharmonic as the grain size decreases. The possible origination of weak ferromagnetism of the nanocrystalline samples has also been discussed.

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