scholarly journals Y3Fe5O12 Nanocatalyst for Green ammonia Production by Using Magnetic Induction Method

2012 ◽  
Vol 21 ◽  
pp. 131-137 ◽  
Author(s):  
Noorhana Yahya ◽  
Poppy Puspitasari
Keyword(s):  
Magnetic Induction ◽  
Ammonia Synthesis ◽  
Sol Gel ◽  
Oxide Phase ◽  
Metallic Phase ◽  
Temperature Program Reduction ◽  
X Ray Diffraction ◽  
Induction Method ◽  
Different Temperatures ◽  
Xrd Patterns

Ammonia production is an energy-intensive industry as it requires high temperature (400-500°C) and also high pressure (150-300bar). This motivates research to finding greener and lower energy process for ammonia synthesis. In this work, Y3Fe5O12(YIG) nanocatalyst that has large surface area was synthesized. Ammonia was produced at ambient environment by using the Magnetic Induction Method (MIM).The Y3Fe5O12nanoparticles were prepared using the sol-gel technique and were sintered at three different temperatures (950-1150°C). The X-Ray Diffraction (XRD) patterns show the major peak at [42 plane with the value of a=b=c=12.38Åwhich indicates a cubic structure. The magnetic saturation (Ms) value of the samples is 16.6emu/g. The reducibility of the particles was described from the Temperature Program Reduction (TPR) profile at 806°C where all the oxide phase is changed to metallic phase. Ammonia yield of 242.56μmole/h.g-cat was successfully obtained at 0°C reaction temperature. It was observed that ammonia synthesis that was conducted at 0°C temperature resulted in higher ammonia yield indicating a better spin alignment and hence improved catalytic activities.

Magnetic Properties of Mg0.4Ca0.6Fe2O4 Nanoparticles Synthesized by Sol-Gel Method for Hyperthermia Treatment

2014 ◽  
Vol 631 ◽  
pp. 193-197
Author(s):  
A.M. Escamilla-Pérez ◽  
D.A. Cortés-Hernández ◽  
J.M. Almanza-Robles ◽  
D. Mantovani ◽  
P. Chevallier
Keyword(s):  
Magnetic Properties ◽  
Sol Gel ◽  
Average Diameter ◽  
X Ray Diffraction ◽  
Hyperthermia Treatment ◽  
X Ray ◽  
Transmission Electron ◽  
Heat Treated ◽  
Different Temperatures ◽  
Xrd Patterns

Powders of Mg0.4Ca0.6Fe2O4were prepared by sol-gel using ethylene glycol and Mg, Ca and Fe nitrates as starting materials. Those powders were heat treated at different temperatures (300, 400, 500 and 600 °C) for 30 min. The materials obtained were characterized by X-ray diffraction (XRD) and vibrating sample magnetometry (VSM). The Ca-Mg ferrite with the most appropriate magnetic properties was further analyzed by transmission electron microscopy (TEM). The heating capability of the nanoferrites was also tested via magnetic induction. The XRD patterns of these Ca-Mg ferrites showed a cubic inverse spinel structure. Furthermore, neither traces of hematite nor orthorhombic Ca ferrite phases were detected. Moreover, all the Ca-Mg ferrites are superparamagnetic and the particle size distribution of these Ca-Mg magnetic nanoparticles exhibits an average diameter within the range of 10-14 nm. The needed temperature for hyperthermia treatment was achieved at around 12 min.

Properties of Y3Fe5O12 (YIG) as Nanocatalyst for Ammonia Formation Produced from Magnetic Induction Method (MIM)

2016 ◽  
Vol 857 ◽  
pp. 146-150 ◽  
Author(s):  
Poppy Puspitasari ◽  
Noorhana Yahya ◽  
Andoko ◽  
Januarti Jaya Ekaputri ◽  
Puput Risdanareni
Keyword(s):  
Magnetic Induction ◽  
Ambient Pressure ◽  
Sol Gel ◽  
Initial Permeability ◽  
X Ray Diffraction ◽  
Induction Method ◽  
Magnetic Nanocatalyst ◽  
X Ray ◽  
Maximum Permeability ◽  
Production Of Ammonia

Production of ammonia required high capital energy intensive such as high temperatures (400 to 500 °C) and high pressure (15 to 30 MPa). We investigated a new way to produce green ammonia synthesis using new nanocatalyst and operate in room temperature and ambient pressure. The idea is to synthesize ammonia using Magnetic Induction Method (MIM) and Y3Fe5O12 (YIG) as magnetic nanocatalyst. YIG was prepared by sol gel method and sintered at various temperatures 950 °C, 1050 °C, and 1150 °C. X-Ray Diffraction (XRD) result shows that the major peak at [420] plane. The balance composition of YIG resulted by Energy Dispersive X-Ray (EDX) is in the form of Y3Fe5O12. Initial permeability results show, the highest value maximum permeability at 140 with the range of frequency 1Hz to100MHz obtained by 950 °C sample. The lowest value of relative loss factor obtained by 950 °C sample. YIG nanocatalyst and MIM method were successfully produce ammonia yield at 197 μmol, without MIM the yield was decreased by 14.28%.

Synthesis, Characterization and Properties of PANI/(La-Nd Doped BaFe12O19) Composites

2017 ◽  
Vol 727 ◽  
pp. 327-334
Author(s):  
Yan Wang ◽  
Jun Wang ◽  
Xiao Fei Zhang ◽  
Ya Qing Liu
Keyword(s):  
Sol Gel ◽  
Network Analyzer ◽  
X Ray Diffraction ◽  
Sem Images ◽  
Structure Morphology ◽  
Xrd Patterns ◽  
Hexagonal Platelet ◽  
Peak Value ◽  
Properties Of Composites

La-Nd co-doped barium hexaferrites, Ba0.7(LamNdn)0.3Fe12O19 (D-BaM), were successfully prepared by sol-gel method. PANI / D-BaM composites were synthesized by in-situ polymerization in solution. The structure, morphology and properties of samples have been characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), vibrating sample magnetometer (VSM), four-probe conductivity tester and vector network analyzer. The XRD patterns showed that the crystal structure of all the samples exist as M-type phases. The SEM images revealed that the particles presented a hexagonal platelet-like morphology. The magnetic properties could be improved by substitutions of La and Nd ions. The saturation magnetization (Ms) and coercive force (Hc) increased with the change of La / Nd ratio to the maximum at La / Nd = 3:1. The doped particles have also been embedded in conductive PANI to prepare electromagnetic materials, and the conductivity kept on the order of 10-2. The microwave absorbing properties of composites at 30 MHz-6 GHz improved obviously, the peak value of reflection loss could reach-7.5 dB.

The effect of silver concentration and calcination temperature on structural and optical properties of ZnO:Ag nanoparticles

2015 ◽  
Vol 29 (01) ◽  
pp. 1450254 ◽  
Author(s):  
M. Shayani Rad ◽  
A. Kompany ◽  
A. Khorsand Zak ◽  
M. E. Abrishami
Keyword(s):  
Calcination Temperature ◽  
Sol Gel ◽  
Visible Emission ◽  
X Ray Diffraction ◽  
Ag Nps ◽  
Zno Nps ◽  
Calcination Temperatures ◽  
Transmission Electron ◽  
Xrd Patterns ◽  
Average Size

Pure and silver added zinc oxide nanoparticles ( ZnO -NPs and ZnO : Ag -NPs) were synthesized through a modified sol–gel method. The prepared samples were characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM) and photoluminescence (PL) spectroscopy. In the XRD patterns, silver diffracted peaks were also observed for the samples synthesized at different calcination temperatures of 500°C, 700°C, 900°C except 1100°C, in addition to ZnO . TEM images indicated that the average size of ZnO : Ag -NPs increases with the amount of Ag concentration. The PL spectra of the samples revealed that the increase of Ag concentration results in the increase of the visible emission intensity, whereas by increasing the calcination temperature the intensity of visible emission of the samples decreases.

Synthesis and Characterization of Cadmium with Titanium Oxide (Cd-TiO2) Nanocomposite: Testing its Antibacterial Effect

2021 ◽  
Vol 12 (4) ◽  
pp. 2523-2529
Author(s):  
Daniel Sam N ◽  
Anish C I ◽  
Sabeena G ◽  
Rajaduraipandian S ◽  
Manobala ◽  
...  
Keyword(s):  
Sol Gel ◽  
Gram Negative Bacteria ◽  
X Ray Diffraction ◽  
Sem Images ◽  
Gram Negative ◽  
X Ray ◽  
Weight Percentage ◽  
Inhibition Concentration ◽  
Xrd Patterns

Sol gel methods were used for the study of the antimicrobial activity of Cd-TiO2 against gram-negative and positive bacteria. These Cd-TiO2 have been characterized by various optical and techniques. They have been exhibited by X-ray diffraction, scanning electron microscopy, ultraviolet spectroscopy, and infrared spectroscopy. The structures of the various XRD patterns indicate that the product has a structure. The particle size of Cd-TiO2 is 35nm. The SEM images confirm the spherical appearance of the sample. The energy X-ray spectra have been confirmed as well and then C, O, Ti, Cd, Pt element are present in Cd-TiO2. The weight percentage of Cadmium is 5.8%, Ti is 51.03%, C is 5.13% and O is 31.75% in Cd-TiO2. BET image shows that the major pore size distribution of Cd-TiO2 is ranged from 2.24 nm. The Cd-TiO2 that the antibacterial activity when tested against the pathogens only gram-negative bacteria such as Pseudomonas. The zone of minimum inhibition concentration was measured in a range of 20mm in 25μl and 30mm in 100μl.

XRD Study of the Influence of Heat Treatment on the Microstructure of Sol-Gel Processed ZrO2-Y2O3 Ceramics

1995 ◽  
Vol 398 ◽  
Author(s):  
C. Barrera-Solano ◽  
M. PiÑero ◽  
C. Jiménez-Solís ◽  
L. Gago-Duport
Keyword(s):  
Heat Treatment ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
Profile Function ◽  
Xrd Study ◽  
Different Temperatures ◽  
Hydrolysis Of Metal Alkoxides ◽  
Induced Changes ◽  
Hydrolysis Of ◽  
Controlled Hydrolysis

ABSTRACTYSZ samples containing 5 and 10 mol% of Y203 were prepared by controlled hydrolysis of metal alkoxides. The dried powders were calcined at 800°C and then they were uniaxially pressed and sintered at different temperatures and next heated at 1400°C (∼ 5 MPa) or annealed at 1600°C for 24 h. The quantitative analysis of the experimental X-ray diffraction (XRD) spectra was performed by Whole Pattern Fitting (WPF). A Pseudo-Voigt (Thompson-Cox-Hastings) was used as shape profile function. The respective phase fractions (wt %) were fitted for both solid state solutions using the scale factor. The heat treatment induced changes are discussed.

LUMINESCENT PROPERTIES OF SOL-GEL DEPOSITED Eu:TiO2 THIN FILMS

2001 ◽  
Vol 15 (17n19) ◽  
pp. 769-773 ◽  
Author(s):  
M. GARCIA-ROCHA ◽  
A. CONDE-GALLARDO ◽  
I. HERNANDEZ-CALDERON ◽  
R. PALOMINO-MERINO
Keyword(s):  
Thin Films ◽  
Sol Gel ◽  
Luminescent Properties ◽  
X Ray Diffraction ◽  
Si Substrates ◽  
Glass Substrates ◽  
Corning Glass ◽  
Different Temperatures ◽  
Hecd Laser

In this work we show the results on tile growth and optical characterization of TiO 2 thin films doped with Eu atoms. Eu:TiO2 films were grown at room temperature with different Eu concentrations by sol-gel on Si Corning glass substrates. A different crystalline structure is developed for the films deposited on Corning glass than those deposited on Si as observed from x-ray diffraction experiments. Room and low temperature photoluminescence (PL) was measured by using two different lines (325 and 442 nm) of a HeCd laser. A strong PL signal associated to the 5 D 0→7 F 2 transition from Eu +3 was observed. A better emission was obtained from those films deposited on Si substrates, Finally, the evolution of the PL signal is studied when the samples are annealed at different temperatures in O 2 atmosphere.

Effect of Annealing Atmosphere on the Morphology of Copper Oxide Thin Films Deposited on TiO2 Substrates Prepared by Sol-Gel Process

2013 ◽  
Vol 594-595 ◽  
pp. 113-117 ◽  
Author(s):  
Dewi Suriyani Che Halin ◽  
Ibrahim Abu Talib ◽  
Abdul Razak Daud ◽  
Muhammad Azmi Abdul Hamid
Keyword(s):  
Thin Films ◽  
Surface Roughness ◽  
Grain Size ◽  
Copper Oxide ◽  
Spin Coating ◽  
Sol Gel ◽  
Annealing Atmosphere ◽  
Oxide Thin Films ◽  
Different Temperatures ◽  
Xrd Patterns

Copper oxide films were prepared via sol-gel like spin coating starting from methanolic solutions of cupric chloride onto the TiO2 substrates. Films were obtained by spin coating under room conditions (temperature, 25-30 °C) and were subsequently annealed at different temperatures (200-400 °C) in oxidizing (air) and inert (N2) atmospheres. X-ray diffraction (XRD) patterns showed crystalline phases, which were observed as a function of the annealing conditions. The film composition resulted single or multi-phasic depending on both temperature and atmosphere. The grain size of film was measured using scanning electron microscopy (SEM) and the surface roughness of thin films was characterized by atomic force microscopy (AFM). The grain size of which was annealed in air at 300 °C was 30.39 nm with the surface roughness of 96.16 nm. The effects of annealing atmosphere on the structure and morphology of copper oxide thin films are reported.

Effect of Annealing Temperature of CoCr2O4 on Structural and Vibrational Properties

2019 ◽  
Vol 11 (11) ◽  
pp. 1079-1081 ◽  
Author(s):  
Prachi Joshi ◽  
Pallavi Saxena ◽  
M. D. Varshney ◽  
V. N. Rai ◽  
A. Mishra
Keyword(s):  
Calcination Temperature ◽  
Sol Gel ◽  
Average Crystallite Size ◽  
Combustion Method ◽  
X Ray Diffraction ◽  
Xrd Pattern ◽  
Auto Combustion ◽  
Different Temperatures ◽  
Disorder Effect ◽  
High Calcination Temperature

CoCr2O4 nanoparticles were prepared by low-temperature sol–gel auto combustion method. In this paper, we have investigated the structural behavior of CoCr2O4 nanoparticles annealed at two different temperatures (600 °C and 800 °C). From the X-ray diffraction (XRD) pattern of CoCr2O4, we have found that there is no change in crystalline structure and it was indexed in the cubic spinel structure with space group Fd3m. It was observed that average crystallite size increases with calcination temperature. High calcination temperature reduced the noise level and enhanced the accuracy of calculated parameters. For both the samples of CoCr2O4, we observed Raman scattering modes at around 471, 516, 539, 561, 590, 626 and 688 cm–1. The additional modes in vibrational spectra appear due to the disorder effect.

Characterization and Photocatalytic Activity of FeVO4 Photocatalysts Synthesized via a Surfactant-Assisted Sol-Gel Method

2011 ◽  
Vol 197-198 ◽  
pp. 926-930
Author(s):  
Min Wang ◽  
Qiong Liu ◽  
Chen Zhi Jiang
Keyword(s):  
Photocatalytic Activity ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
Experimental Conditions ◽  
Gel Method ◽  
Sol Gel Method ◽  
Photodegradation Rate ◽  
Photocatalytic Activities ◽  
Xrd Patterns ◽  
Surfactant Assisted

FeVO4photocatalysts were synthesized via a surfactant-assisted sol-gel method and characterized with X-ray diffraction (XRD), scanning electron microsoope （SEM）and specific surface area (BET). The photocatalytic activity was evaluated by photocatalytic degradation of methyl orange (MO) solution under visible light. The XRD patterns of no-surfactant-assisted, PEG-assisted, CTAB-assisted and SDS-assisted FeVO4, indicate that diffraction peaks can be well indexed as triclinc FeVO4. And the crystalline sizes of samples were evaluated as 113, 69, 66, 76 nm for FVO, FVO-PEG, FVO-CATB and FVO-SDS respectively.The addition of surfactant woul greatly affect the morphology of FeVO4photocatalysts, which can lead to different photocatalytic activities between them. In the experimental conditions used, the PEG-assisted FeVO4product had a much higher photocatalytic activity (the photodegradation rate was about 77% or so in 14h) than the other three products.

Sign in / Sign up

Export Citation Format

Share Document