Influence of the metal nitrates to citric acid molar ratio on the combustion process and phase constitution of barium hexaferrite particles prepared by sol–gel combustion method

Holmium-doped BaTiO3 with composition Ba0.97Ho0.03TiO3 was prepared by sol-gel combustion method. A molar ratio of citrate/nitrate (CA/NO3− = 1.3) was used to prepare nanopowders of (Ba,Ho)TiO3. The structure and microstructure of (Ba,Ho)TiO3 powders and ceramics were investigated. The ceramics exhibit a dielectric constant of about 4400 and dielectric loss (tan δ = 0.267) at 10 Hz, and at the Curie temperature (Tc = 132 °C). The remanent polarization and the coercive field of Ba0.97Ho0.03TiO3 ceramics, at 1 kHz, were Pr = 6 μC/cm2 and EC = 0.75 kV/cm. The dielectric and ferroelectric behavior of the holmium-doped BaTiO3 is influenced by the amphoteric character of Ho3+ ions.

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Synthesis and sintering of nanocrystalline hydroxyapatite powders by citric acid sol–gel combustion method

Materials Research Bulletin ◽

10.1016/j.materresbull.2003.09.022 ◽

2004 ◽

Vol 39 (1) ◽

pp. 25-32 ◽

Cited By ~ 126

Author(s):

Yingchao Han ◽

Shipu Li ◽

Xinyu Wang ◽

Xiaoming Chen

Keyword(s):

Citric Acid ◽

Sol Gel ◽

Combustion Method ◽

Nanocrystalline Hydroxyapatite ◽

Gel Combustion ◽

Gel Combustion Method

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A Comparative Study on Magnetostructural Properties of Barium Hexaferrite Powders Prepared by Polyethylene Glycol

Journal of Nanomaterials ◽

10.1155/2014/302350 ◽

2014 ◽

Vol 2014 ◽

pp. 1-7 ◽

Cited By ~ 9

Author(s):

Zehra Durmus

Keyword(s):

Polyethylene Glycol ◽

Magnetic Measurements ◽

Sol Gel ◽

Barium Hexaferrite ◽

Xrd Analysis ◽

Sem Analysis ◽

Molar Ratio ◽

Molecular Weights ◽

Metal Nitrates ◽

Gel Combustion

Nanocrystalline particles of barium hexaferrite were synthesized by a sol-gel combustion route using nitrate-citrate gels prepared from metal nitrates and citric acid solutions with Fe/Ba molar ratio 12. The present paper aims to study the effect of addition of polyethylene glycol (PEG) solutions with different molecular weights (MW: 400, 2000, and 10.000 g/mol) on magnetostructural properties of barium hexaferrite. The formation of the barium hexaferrite was inspected using X-ray diffraction (XRD) analysis, Fourier transform infrared (FT-IR) analysis, thermogravimetric (TGA) analysis, scanning electron microscopy (SEM) analysis and vibrating sample magnetometer (VSM) analysis for magnetic measurements.

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Effect of the Fuel Type on the Synthesis of Barium Strontium Titanate by Sol-Gel Combustion Method

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.802.149 ◽

2013 ◽

Vol 802 ◽

pp. 149-153

Author(s):

Chanyaphak Thongchanthep ◽

Sarawut Thountom

Keyword(s):

Acid Treatment ◽

Perovskite Phase ◽

Sol Gel ◽

Combustion Method ◽

Ferroelectric Ceramic ◽

Molar Ratio ◽

Tem Analysis ◽

Barium Strontium ◽

Gel Combustion ◽

Gel Combustion Method

The ferroelectric ceramic, Barium Strontium Tinanate (Ba0.7Sr0.3TiO3), was prepared by the sol-gel combustion method using citric acid, urea, and glycine as the fuel for reduce the calcination temperature. The molar ratio of sol powderto fuel was 1:1. All of the samples were calcined at 450, 550, 650, 750, 850 and 950°C for 2 h. Then,Ba0.7Sr0.3TiO3powders were applied with acid treatment process. X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and Transmission Electron Microscope (TEM) analysis were used to characterize the crystal structure and microstructure. The perovskite phases of BST and the pyrochlore (BaCO3,SrCO3) were obtained after the calcinations temperature of 550°C. BST powders were applied with acid treatment process.The XRD result showed the pure perovskite phase without the phase of pyrochlore in all of the samples. Ba0.7Sr0.3TiO3was in cubic structure, corresponding to JCPDS 34-0411. SEM analysis of BST powders calcined at 750°C.The particles were spherical morphology and had agglomerates while the particles sizes were larger corresponding with the increase of calcinations temperature.The results for TEM analysis of the BST powders prepared by using urea as the fuel had a smaller particles,and the average of particle size was about 47 nm.

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The effect of citric acid to metal nitrates molar ratio on sol–gel combustion synthesis of nanocrystalline LaMnO3 powders

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2008.11.068 ◽

2009 ◽

Vol 478 (1-2) ◽

pp. 493-497 ◽

Cited By ~ 64

Author(s):

Yuanyuan Li ◽

Lihong Xue ◽

Lingfang Fan ◽

Youwei Yan

Keyword(s):

Citric Acid ◽

Combustion Synthesis ◽

Sol Gel ◽

Molar Ratio ◽

Metal Nitrates ◽

Gel Combustion

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Characteristics of barium hexaferrite nanocrystalline powders prepared by a sol-gel combustion method using inorganic agent

Journal of Electroceramics ◽

10.1007/s10832-007-9206-3 ◽

2007 ◽

Vol 21 (1-4) ◽

pp. 357-360 ◽

Cited By ~ 13

Author(s):

A. Ataie ◽

A. Mali

Keyword(s):

Sol Gel ◽

Barium Hexaferrite ◽

Combustion Method ◽

Nanocrystalline Powders ◽

Gel Combustion ◽

Gel Combustion Method

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Synthesis of nano Mn-Zn ferrites by gel combustion method with three different fuels and investigation of their structure and properties

Materials Science-Poland ◽

10.2478/msp-2020-0037 ◽

2020 ◽

Vol 38 (2) ◽

pp. 350-358

Author(s):

Nima Vahdati ◽

Arman Sedghi

Keyword(s):

Electron Microscopy ◽

Magnetic Properties ◽

Citric Acid ◽

Rietveld Method ◽

Combustion Process ◽

Simultaneous Thermal Analysis ◽

Combustion Method ◽

Gel Combustion ◽

Organic Fuels ◽

Gel Combustion Method

AbstractThe purpose of studying the properties of zinc-manganese nanoferrite was to compare organic fuels that were produced in conditions created by the auto gel combustion method, using citric acid, glycine, and urea with different pH values: (citric acid = 6, glycine = 3 and urea = 0). The samples were prepared in stoichiometric ratios to gain Mn0.5Zn0.5Fe2O4, and all the samples were calcined in the same condition (500 °C and 30 minutes). It should be noted that the entire process of synthesis was photographed to analyze the effect of fuels during the combustion process. Combustion reactions were studied by simultaneous thermal analysis (STA), FT-IR spectroscopy, and X-ray diffraction (XRD), also the Rietveld method was used to determine the type and amount of crystalline phases. Magnetic properties of the samples were measured by vibration sample magnetometer (VSM), and their morphology and powder agglomeration was observed by field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). Superior magnetic properties of the sample synthesized with glycine were achieved. Urea gave the smallest particle size, while citric acid produced intermediate properties.

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