scholarly journals Preparation of Crystalline LaFeO3 Nanoparticles at Low Calcination Temperature: Precursor and Synthesis Parameter Effects

Materials ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 5534
Author(s):  
Wen Jiang ◽  
Liwei Cheng ◽  
Jianghui Gao ◽  
Shiyu Zhang ◽  
Hao Wang ◽  
...  
Keyword(s):  
Calcination Temperature ◽  
X Ray Diffraction ◽  
Experimental Conditions ◽  
Calcination Process ◽  
Calcination Temperatures ◽  
Lanthanum Ferrite ◽  
Lafeo3 Nanoparticles ◽  
Wet Chemical ◽  
Agglomeration Of Nanoparticles ◽  
Substantial Effort

Substantial effort has been devoted to fabricating nanocrystalline lanthanum ferrite (LaFeO3), and calcination is the crucial process of crystallization in both high-temperature strategies and wet chemical methods. Lowering the calcination temperature gives the ability to resist the growth and agglomeration of nanoparticles, therefore contributing to preserve their unique nanostructures and properties. In this work, we prepared crystalline LaFeO3 nanoparticles with a calcination process at 500 °C, lower than the calcination temperature required in most wet chemistry methods. Correspondingly, the experimental conditions, including stoichiometric ratios, pH values, precipitants, complexant regent, and the calcination temperatures, were investigated. We found that the crystalline LaFeO3 was formed with crystalline NaFeO2 after calcination at 500 °C. Furthermore, the structure of FeO6 octahedra that formed in coprecipitation was associated with the process of crystallization, which was predominantly determined by calcination temperature. Moreover, an illusion of pure-phase LaFeO3 was observed when investigated by X-ray diffraction spectroscopy, which involves amorphous sodium ferrite or potassium ferrite, respectively. These findings can help prepare nanostructured perovskite oxides at low calcination temperatures.

Influence of Calcination Temperature towards Fe-TiO2 for Visible-Driven Photocatalyst

2017 ◽  
Vol 888 ◽  
pp. 435-440 ◽  
Author(s):  
Siti Aida Ibrahim ◽  
Muhamad Nazim Ahmid
Keyword(s):  
Visible Light ◽  
Calcination Temperature ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
Combined Method ◽  
Calcination Process ◽  
Calcination Temperatures ◽  
Light Region ◽  
Average Grain Size ◽  
Vis Spectroscopy

TiO2 is one of the most promising photocatalysts that is widely used for environmental clean-up due to its ability to degrade organic pollutants in air or water. The purpose of this study is to enhance the photocatalytic activity of TiO2 by absorbing energy in visible light region in order to degrade pollutants. In this study, the nanostructured Fe-TiO2 was successfully synthesised via a combined method of sol-gel and calcination process. The calcination temperatures used varied from 400 to 800 °C. The as-prepared samples were characterized by X-ray diffraction (XRD), FESEM and UV-Vis spectroscopy (UV-Vis). XRD results show that the phases of TiO2 are dependent on calcination temperature. It is found that both TiO2 and Fe-TiO2 phases were transformed from anatase to rutile as the temperatures were increased. FESEM images revealed that the particle size was agglomerated and the average grain size was about 54 to 66 nm. UV-Vis analysis indicated that the incorporation of Fe and varied calcination temperature may affect the optical properties as the absorption profile was shifted from 445 nm to 585 nm. Thus, this results show that Fe-TiO2 is a highly potential photocatalyst to degrade pollutants under visible light irradiation.

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.

scholarly journals Hydroxyapatite Extracted from Waste Fish Bones and Scales via Calcination Method

2015 ◽  
Vol 773-774 ◽  
pp. 287-290 ◽  
Author(s):  
N. Mustafa ◽  
Mohd Halim Irwan Ibrahim ◽  
Rosli Asmawi ◽  
Azriszul Mohd Amin
Keyword(s):  
Chemical Reaction ◽  
Fish Bone ◽  
Powder Size ◽  
X Ray Diffraction ◽  
Calcination Process ◽  
X Ray ◽  
Calcination Temperatures ◽  
Hydroxyapatite Powder ◽  
Before And After ◽  
Calcination Method

A hydroxyapatite is known as one of vital materials and common use in biomedical field and concentrated in clinical area. In relation to the above, the development of hydroxyapatite powder becomes an attractive research lines due to simplify in produce it. Thus in this paper the researcher stress out about Hydroxyapatite powder gained from the natural sources or so called as the waste of Tilapia bone and scales. The raw bones of and scale were undergo to crushing process to form in powder size (0.2 mm) then analysed by X-ray Diffraction (XRD) to identified the mineralogy of raw bone. Moreover the powder of fish bone and scales also go through to Scanning Electron Microscope (SEM) machine to analyse the microstructure of the powder while EDS act as device to determine the chemical composition of the sample powder. Sample powder then forward calcination process at selected temperature range to as a cheaper method in obtained hydroxyapatite raw sources. The range of calcination temperatures are between 800°C to 1000 °C. The sample preparation were analysed in both condition before and after calcination process by using XRD, SEM and EDS. The HAP crystalline composition of tilapia bones for raw powder and at 800 °C are similar with HAP pattern (JDS 00-009-0432) and the chemical reaction is Ca5(PO4)3(OH) then at temperature 900 and 1000 similar to HAP pattern (JDS 00-055-0592) with chemical reaction equal to Ca10(PO4)6(OH)2.

The Effect of Calcination Temperature on Electrochemical Performance of Porous LaMnO3 Catalyst in Al-Air Battery

2017 ◽  
Vol 727 ◽  
pp. 657-662 ◽  
Author(s):  
Fu Wei Xiang ◽  
Xiu Hua Chen ◽  
Hui Wen Ma ◽  
Jie Yu ◽  
Hui Zhang ◽  
...  
Keyword(s):  
Calcination Temperature ◽  
Discharge Voltage ◽  
Cell Polarization ◽  
X Ray Diffraction ◽  
Half Cell ◽  
X Ray ◽  
Calcination Temperatures ◽  
Cell Discharge ◽  
Air Battery ◽  
Discharge Test

This study focuses on the development of the pervoskite catalyst for aluminum-air battery. The catalyst powders of porous pervoskite LaMnO3 were prepared by template method with different calcination temperatures. Material characteristics of prepared samples were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and thermalgravimetry (TG). The half-cell polarization curves and cyclic voltammetry curves were found to be strongly depended on the calcination temperature. The result showed the optimized calcination temperature was 650°C. The full-cell discharge test in NaCl solution (3.5 wt%) with a constant discharge current of 10 mA/cm2 was performed at room temperature, and the discharge voltage of sample synthesized under optimized calcination temperature was 0.73 V.

scholarly journals Effect of Calcination Temperature on the Synthesis of ZrO2-Pillared Saponite to Catalytic Activity in Menthol Esterification

2018 ◽  
Vol 16 (1) ◽  
pp. 8 ◽  
Author(s):  
Is Fatimah ◽  
Dwiarso Rubiyanto ◽  
Nanda Candra Kartika
Keyword(s):  
Catalytic Activity ◽  
Surface Area ◽  
Calcination Temperature ◽  
Surface Acidity ◽  
Physicochemical Characteristics ◽  
Sem Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Calcination Temperatures ◽  
Solid Acidity

The influence of calcination temperature on the synthesis of zirconia-pillared saponite (PILS) and on its catalytic activity in menthol esterification has been studied. Zirconia pillarization was conducted using zirconium tetraisopropoxide as a precursor and with calcination temperatures of 450, 600 and 700 °C. Evaluation of physicochemical characteristics at these varied temperatures was carried out by X-Ray Diffraction (XRD), surface area analysis, Scanning Electron Eicroscope (SEM) analysis, Differential Thermal Analysis (DTA) and total acidity. The obtained results indicate that the structure and surface acidity of saponite were strongly influenced by calcination temperature. The solid acidity and surface parameters such as specific surface area, pore volume, and pore radius play an important role in the total conversion and selectivity in menthol esterification.

scholarly journals SYNTHESIS AND CHARACTERIZATION OF Fe2O3 NANOPARTICLES USING Averrhoa bilimbi AS BIOMATERIAL CHELATING AGENT FOR NANOFLUIDS APPLICATION

2017 ◽  
Vol 13 (2) ◽  
pp. 133 ◽  
Author(s):  
Arie Hardian ◽  
Alvi Aristia Ramadhiany ◽  
Dani Gustaman Syarif ◽  
Senadi Budiman
Keyword(s):  
Calcination Temperature ◽  
Sol Gel ◽  
Chelating Agent ◽  
Xrd Analysis ◽  
Solid Particles ◽  
X Ray Diffraction ◽  
Calcination Temperatures ◽  
Basic Fluid ◽  
Sol Gel Synthesis

<p>The aim of this work was to determine the effect of calcination temperature on the characteristics of Fe<sub>2</sub>O<sub>3</sub> nanoparticles (NPs) in sol-gel synthesis. The obtained Fe<sub>2</sub>O<sub>3 </sub>NPs was then used as material for preparation of Fe<sub>2</sub>O<sub>3</sub>-water nanofluids. Nanofluids is a mixture between basic fluid like water and 1 - 100 nm solid particles (nanoparticles). Nanoparticles of Fe<sub>2</sub>O<sub>3</sub> have been synthesized from the local mineral Jarosite using sol-gel method by using starfruit (<em>Averrhoa bilimbi</em>) extracts as the chelating agent. The calcination temperature was then varied from 500 ºC to 700 ºC for 5 hours. Based on the X-Ray Diffraction (XRD) analysis, the diffraction pattern of obtained Fe<sub>2</sub>O<sub>3</sub> was relevant with the JCPDS data No. 33-0664 for α-Fe<sub>2</sub>O<sub>3 </sub>with hexagonal crystallite system. The crystallite size (Scherrer’s Equation) of obtained α-Fe<sub>2</sub>O<sub>3</sub> nanoparticles at calcination temperatures of 500 ºC, 600 ºC and 700 ºC was 50 nm, 48 nm and 40 nm, respectively. The Surface Area of Fe<sub>2</sub>O<sub>3</sub> NPs at temperature of 500 ºC, 600 ºC and 700 ºC was 45.45 m<sup>2</sup>/g; 26.91 m<sup>2</sup>/g and 17.51 m<sup>2</sup>/g, respectively. Fe<sub>2</sub>O<sub>3</sub>-water nanofluids was relativly stable with zeta potential of -39.60 mV; -46.37 mV and -41.57 mV, respectively for 500 ºC, 600 ºC and 700 ºC calcination temperature. The viscosity of Fe<sub>2</sub>O<sub>3</sub>-water nanofluids was higher than the viscosity of water. The critical heat flux (CHF) value of water-Fe<sub>2</sub>O<sub>3</sub> nanofluids was higher than the CHF water. The highest CHF value for nanofluids was obtained by using α-Fe<sub>2</sub>O<sub>3</sub> nanoparticles with calcination temperature of 600 ºC which 34.99 % of increment compare to the base fluid (water).</p>

Structural and Magnetic Properties of Ni0.5Zn0.5Fe2O4 Synthesized through the Sol-Gel Method

2014 ◽  
Vol 664 ◽  
pp. 75-79
Author(s):  
Beh Hoe Guan ◽  
Muhammad Hanif Zahari ◽  
Lee Kean Chuan
Keyword(s):  
Magnetic Properties ◽  
Calcination Temperature ◽  
Sol Gel ◽  
Vibrating Sample Magnetometer ◽  
X Ray Diffraction ◽  
Gel Method ◽  
X Ray ◽  
Sol Gel Method ◽  
Calcination Temperatures ◽  
Zn Ferrite

This study investigates the influence of calcination temperatures on the magnetic properties of Ni0.5Zn0.5Fe2O4(Ni-Zn) ferrites.Ni-Zn ferrite with the chemical formula Ni0.5Zn0.5Fe2O4was prepared from their respective nitrate salts through the sol-gel method. The resulting ferrites were characterized using X-ray diffraction (XRD), field emission scanning electron microscope (FESEM) and vibrating sample magnetometer (VSM). Single phased Ni0.5Zn0.5Fe2O4 was obtained at all calcination temperatures.FESEM Micrographs reveals an increase in the grain size with the increase of the calcination temperature. Consequently, the magnetic saturation of the samples were found to increase with each increase in the calcination temperature where the highest value obtained is 70.58 emu/g for the samples calcined at 1000°C.

Raman and magnetization studies of barium ferrite powder prepared by water-in-oil microemulsion

2000 ◽  
Vol 15 (2) ◽  
pp. 483-487 ◽  
Author(s):  
M. S. Chen ◽  
Z. X. Shen ◽  
X. Y. Liu ◽  
J. Wang
Keyword(s):  
Magnetic Properties ◽  
Calcination Temperature ◽  
Raman Spectra ◽  
Ferrite Powder ◽  
X Ray Diffraction ◽  
Ferric Ions ◽  
Frequency Shifts ◽  
X Ray ◽  
Calcination Temperatures ◽  
Crystallization Effect

Micro-Raman spectroscopy was used to study the formation of BaFe12O19 (BaM) powders derived from water-in-oil microemulsion at different calcination temperatures. With increase in the calcination temperature, the Raman spectra of the BaM powders become narrower and stronger without apparent frequency shifts of the Raman bands. The calcination temperature dependence of the Raman spectra and the magnetic properties of the BaM powders result from the crystallization rather than size effect. Our results show that there is a strong correlation between the crystallinity and the magnetic properties, which could be explained in terms of the crystallization effect on the superexchange interaction between ferric ions. The γ–Fe2O3 phase occurred in the BaM precursor and the powder calcined at 500 °C. The α–Fe2O3 phase was developed in the powders calcined at 500, 600, and 700 °C, which was not detected by x-ray diffraction. With increasing calcination temperature, the γ–Fe2O3 phase can either react with oxide containing barium to form the BaM phase or transform to the α–Fe2O3 phase. The amount of α–Fe2O3 decreases due to reaction with BaCO3 to form BaM phase at higher calcination temperature.

Influence of Calcination on the Properties of La0.6Sr0.4Co0.2Fe0.8O3-δ-Samarium Doped Ceria Carbonate

2013 ◽  
Vol 465-466 ◽  
pp. 949-953
Author(s):  
Hamimah A. Rahman ◽  
Andanastuti Muchtar ◽  
Norhamidi Muhamad ◽  
Huda Abdullah
Keyword(s):  
Solid Oxide Fuel Cells ◽  
Calcination Temperature ◽  
Composite Cathode ◽  
Doped Ceria ◽  
X Ray Diffraction ◽  
Composite Powders ◽  
Surface Exchange ◽  
Calcination Temperatures ◽  
Composite Cathodes ◽  
Oxygen Surface Exchange

The correlation between calcination temperature and properties (physical and electrochemical) of composite cathodes comprising lanthanum strontium cobaltite ferrite (LSCF) with samarium-doped ceria carbonate (SDCC) has been investigated. LSCF-SDC carbonate (LSCF-SDCC) composite cathode powders prepared via ball-milling were calcined at various temperatures in the range of 700850 °C. X-ray diffraction (XRD) results confirmed that the applied calcination temperatures do not affect the chemical compatibility and the LSCF perovskite cubic structure of the composite powders. FTIR spectra verified the presence of carbonates in the composite powders after calcination. The increment of the calcination temperature reduced the surface area of the particle from 10.9 m2/g to 6.5 m2/g. The electrochemical results revealed that the resistance of LSCF-SDC carbonate composite cathodes is dominated by the oxygen surface exchange reaction at the electrode surface. 750 °C was identified as the most appropriate calcination temperature for the LSCF-SDC carbonate powder when the cathode electrode showed the lowest resistance with conductivity value of 0.95 x 10-3 Scm-1. The findings are of potential relevance to utilizing the LSCF-SDC carbonate cathodes for low temperature solid oxide fuel cells (LT-SOFC).

Structural Properties Dependence on Annealing Temperature of 1-D Lanthanum Iron Garnet Nanofiber Prepared via Electrospinning Technique

2019 ◽  
Vol 59 ◽  
pp. 105-111
Author(s):  
Mohamad Ashry Jusoh ◽  
Fahmiruddin Esa ◽  
Rodziah Nazlan
Keyword(s):  
Calcination Temperature ◽  
Structural Properties ◽  
Annealing Temperature ◽  
Structure Change ◽  
X Ray Diffraction ◽  
Electrospinning Technique ◽  
Calcination Process ◽  
X Ray ◽  
Continuous Structure ◽  
Iron Garnet

The effect of anealing temperature on structural properties of Lanthanum Iron Garnet (LIG) nanofiber has been studied. The LIG nanofiber were prepared by electrospinning technique. This technique has been extensively developed as a simple and efficient method for drawing nanofibers from polymer solutions. The viscous LIG solution were loaded in syringe and were pumped at 0.05 mL/h. The nanofibers were collected on aluminium foil and were treated at 700 °C, 750 °C and 1000 °C in order to study the effect of annealing temperature to the nanofibers structure. X-Ray Diffraction (XRD) and Field Emission Scanning Electron Microscope (FESEM) were employed to study the phase formation and morphology of the samples. The XRD results of LIG nanofiber reveals that as the annealing temperature increases from 700 °C to 1000 °C, the corresponding peaks become sharper and narrower, which demonstrate the improvement of crystallinity and crystallite size. The FESEM images of LIG nanofiber demonstrates that the nanofibers treated at 700 °C have continuous structure with a relatively rough surface and their diameter range is within 41.3 nm and 58.7 nm. Subsequently, when the calcination temperature increase further, the morphology of the sample is dramatically changed. As calcinations temperature rises to 750 °C, the surface of resultant nanofibers start to become agglomerate due to the growth and coalescence of the particle in the nanofibers under the calcination process and the nanofibers structure change back to continuous structure with bigger diameter at 1000 °C as compared to calcination temperature of 700 °C.

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