Synthesis and Characterization of Pure Barium Ferrite Prepared by a Glycine - Metal Nitrate Combustion Method

1991 ◽  
Vol 249 ◽  
Author(s):  
Manson L. Wade ◽  
David G. Agresti

ABSTRACTA combustion-synthesis method [Chick et al., Materials Letters 10, 6 (1990)] has been adapted for the efficient preparation of pure barium ferrite particles, BaFe12O19. Solutions of Ba(NO3)2 and Fe(NO3)3 · 9H2O were mixed in stoichiometric amounts and glycine (aminoacetic acid) was then added according to the desired glycine / nitrate ratio. The solution was heated to around 200°C, when combustion occured, yielding a highly magnetic ash, which XRD suggests consists of extremely fine-grained γ-Fe2O3 and Ba3Fe2O6. Subsequent heat-treatments of 1050°C for 1.5 hr or 1200°C for 1 hr converted the ash to pure barium ferrite, as determined by XRD and Mdssbauer spectroscopy. Single-crystal platelets of barium ferrite, identified by SEM, varied dramatically in size with heat-treatment (diameter ∼0.2 pm and 6 μm, respectively), as did coercivity, measured by VSM (∼5000 Oe and 2500 Oe, resp.), while magnetization was unaffected.

2012 ◽  
Vol 545 ◽  
pp. 169-171 ◽  
Author(s):  
Mawar Hazwani Jasimin ◽  
Nurhanna Badar ◽  
Rusdi Roshidah ◽  
Norlida Kamarulzaman

Aluminium oxide is one of the metal oxides that can exist in many phases such as α, θ, η etc. All the phases obtained are affected by annealing temperature and synthesis route. In this research the Al2O3 powders were synthesized by the combustion method using triethanolamine as fuels. A pure η phase as well as a mixed α and η phases were obtained. The size and morphology of Al2O3 particles were studied using scanning electron microscopy (SEM).


2021 ◽  
Vol 44 (3) ◽  
Author(s):  
T KALAIARASI ◽  
M SENTHILKUMAR ◽  
S SHANMUGAN ◽  
T JARIN ◽  
V CHITHAMBARAM ◽  
...  

2020 ◽  
Vol 43 (1) ◽  
pp. 26-42 ◽  
Author(s):  
Zahra Hajian Karahroudi ◽  
Kambiz Hedayati ◽  
Mojtaba Goodarzi

AbstractThis study presents a preparation of SrFe12O19– SrTiO3 nanocomposite synthesis via the green auto-combustion method. At first, SrFe12O19 nanoparticles were synthesized as a core and then, SrTiO3 nanoparticles were prepared as a shell for it to manufacture SrFe12O19–SrTiO3 nanocomposite. A novel sol-gel auto-combustion green synthesis method has been used with lemon juice as a capping agent. The prepared SrFe12O19–SrTiO3 nanocomposites were characterized by using several techniques to characterize their structural, morphological and magnetic properties. The crystal structures of the nanocomposite were investigated via X-ray diffraction (XRD). The morphology of SrFe12O19– SrTiO3 nanocomposite was studied by using a scanning electron microscope (SEM). The elemental composition of the materials was analyzed by an energy-dispersive X-ray (EDX). Magnetic properties and hysteresis loop of nanopowder were characterized via vibrating sample magnetometer (VSM) in the room temperature. Fourier transform infrared spectroscopy (FTIR) spectra of the samples showed the molecular bands of nanoparticles. Also, the photocatalytic behavior of nanocomposites has been checked by the degradation of azo dyes under irradiation of ultraviolet light.


2013 ◽  
Vol 594-595 ◽  
pp. 73-77 ◽  
Author(s):  
Sze Mei Chin ◽  
Suriati Sufian ◽  
Jeefferie Abd Razak

This paper highlights on the hydrogen production through photocatalytic activity by using hematite nanoparticles synthesized from self-combustion method based on different stirring period. The morphologies and microstructures of the nanostructures were determined using Field-Emission Scanning Electron Microscope (FESEM), X-Ray Diffractometer (XRD) and Particle Size Analyser (PSA). Besides that, surface area analyser was used to determine the BET surface area of the hematite samples. The hematite nanocatalyst as-synthesized are proven to be rhombohedral crystalline hematite (α-Fe2O3) with particle diameters ranging from 60-140 nm. The BET specific surface area of hematite samples increased from 5.437 to 7.6425 m2/g with increasing stirring period from 1 to 4 weeks. This caused the amount of hydrogen gas produced from photocatalytic water splitting to increase as well.


2008 ◽  
Vol 93 (1) ◽  
pp. 210-216 ◽  
Author(s):  
F. M. McCubbin ◽  
H. E. Mason ◽  
H. Park ◽  
B. L. Phillips ◽  
J. B. Parise ◽  
...  

Inorganics ◽  
2018 ◽  
Vol 6 (3) ◽  
pp. 97 ◽  
Author(s):  
Marie Gaschard ◽  
Farzaneh Nehzat ◽  
Thomas Cheminel ◽  
Bruno Therrien

The synthesis and characterization of three metalla-rectangles of the general formula [Ru4(η6-p-cymene)4(μ4-clip)2(μ2-Lanthr)2][CF3SO3]4 (Lanthr: 9,10-bis(3,3’-ethynylpyridyl) anthracene; clip = oxa: oxalato; dobq: 2,5-dioxido-1,4-benzoquinonato; donq: 5,8-dioxido-1,4-naphthoquinonato) are presented. The molecular structure of the metalla-rectangle [Ru4(η6-p-cymene)4(μ4-oxa)2(μ2-Lanthr)2]4+ has been confirmed by the single-crystal X-ray structure analysis of [Ru4(η6-p-cymene)4(μ4-oxa)2(μ2-Lanthr)2][CF3SO3]4 · 4 acetone (A2 · 4 acetone), thus showing the anthracene moieties to be available for reaction with oxygen. While the formation of the endoperoxide form of Lanthr was observed in solution upon white light irradiation, the same reaction does not occur when Lanthr is part of the metalla-assemblies.


Synlett ◽  
2018 ◽  
Vol 30 (01) ◽  
pp. 54-58 ◽  
Author(s):  
Timothy Swager ◽  
Cagatay Dengiz ◽  
You-Chi Wu

We report the synthesis and characterization of iptycene–naphthazarin dyes by using a sequential Diels–Alder approach. The tautomerization of naphthazarin was used as the key step in the synthesis, with structures confirmed by single-crystal X-ray and NMR analysis. The systematic trends in electronic properties were investigated by UV/Vis spectroscopy. BF2 complexes of the dyes were prepared by reaction with BF3·OEt2 in CH2Cl2.


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