Monodispersed Sc2O3 precursor particles via homogeneous precipitation: Synthesis, thermal decomposition, and the effects of supporting anions on powder properties

Monodispersed Sc2O3 precursor particles were synthesized by the urea-based homogeneous precipitation method, with an investigation into the effects of supporting anions (NO3−, Cl−, and SO4 2−) on powder properties. Characterizations of the powders were achieved by elemental analysis, x-ray diffractometry, Fourier transform infrared, differential thermal analysis/thermogravimetry, high-resolution scanning electron microscopy, and the Brunauer-Emmett-Teller method. Unlike other rare earths, Sc3+ does not precipitate as basic carbonate but instead forms hydrated γ-ScOOH from either nitrate or chloride solution. Particles of the hydrated γ-ScOOH are pumpkin-shaped (approximately 1.0 μm) and are made up of thin-platelike crystallites emanating from a common axis. The presence of complexing SO42− changes the reaction chemistry toward Sc2O3 powders, leading to basic sulfate [Sc(OH)1.6(SO4)0.7 η H2O] precursor particles having hexagonal morphology (approximately 10 μm in diameter and 0.5 μm in thickness). The hydrated γ-ScOOH directly converts to Sc2O3 by calcination at 400 °C or above, while the basic sulfate transforms to oxide at temperatures ≥ 900 °C via an amorphous state and a Sc2(SO4)3 intermediate. The effect of SO42− on powder morphologies and reaction chemistry is discussed. Nanocrystalline Sc2O3 powders comprising monodispersed particles were obtained via thermal decomposition of the precursors.

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Preparation of α-Ni(OH)2 with Flowerlike Hierarchical Architectures via Homogeneous Precipitation Method

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.284-286.684 ◽

2011 ◽

Vol 284-286 ◽

pp. 684-687

Author(s):

Chang Yu Li ◽

Li Li Liu ◽

Shou Xin Liu

Keyword(s):

Electron Microscopy ◽

Precipitation Method ◽

Homogeneous Precipitation ◽

X Ray ◽

Homogeneous Precipitation Method ◽

Α Phase ◽

Transmission Electron ◽

Hierarchical Architectures ◽

Flowerlike Structure ◽

Adsorption Desorption

Without using any templates or surfactants, flowerlike α-nickel hydroxide (Ni(OH)2) was successfully synthesized by homogeneous precipitation method. The prepared products were characterized by X-ray powder diffraction (XRD), high-resolution transmission electron microscopy (HRTEM) and N2 adsorption-desorption. The prepared Ni(OH)2 is α-phase with specific surface area of 245.0 m2/g and shows flowerlike structure with 4-6 um in diameter.

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Synthesis of Porous Basic Magnesium Carbonate Crystallographic Materials with Flower-Like Structure

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.723.444 ◽

2016 ◽

Vol 723 ◽

pp. 444-449 ◽

Cited By ~ 1

Author(s):

Juan Chen ◽

Zhi Liang Huang ◽

Wen Zhao Li

Keyword(s):

Electron Microscopy ◽

Magnesium Carbonate ◽

Precipitation Method ◽

Homogeneous Precipitation ◽

Experimental Equipment ◽

X Ray Diffraction ◽

X Ray ◽

Homogeneous Precipitation Method ◽

Chloride Hexahydrate ◽

Scanning Electron

The porous basic magnesium carbonate (Mg5(CO3)4(OH)2.4H2O) crystal crystallographic materials with flower-like structure were prepared successfully by homogeneous precipitation method. Magnesium chloride hexahydrate (MgCl2.6H2O) and urea (CO(NH2)2) wereused as reaction materials. The experimental equipment was held at 100°C for 8 h. Phase and morphology of the product were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The formation mechanism of the product was investigated. It was found that the CO2 bubbles acted as porous templates. The growth and gathering of the CO2 bubbles induced the growth of the MgCO3.3H2O columnar crystals. Then the dissolution of the MgCO3.3H2O and the deposition of Mg5(CO3)4(OH)2.4H2O happened simultaneously. Finally the disappearance of MgCO3.3H2O brought about the formation of the porous structure.

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Synthesis and Characterization of BaCO3 Nanoparticles with Different Morphologies by Microwave Homogenous Precipitation

High Temperature Materials and Processes ◽

10.1515/htmp-2012-0058 ◽

2013 ◽

Vol 32 (1) ◽

pp. 47-50

Author(s):

Guo Chen ◽

Jin Chen ◽

Lijun Liu ◽

C. Srinivasakannan ◽

Jinhui Peng

Keyword(s):

Raw Materials ◽

Precipitation Method ◽

Synthesis And Characterization ◽

Homogeneous Precipitation ◽

Tetraacetic Acid ◽

X Ray ◽

Homogeneous Precipitation Method ◽

Scanning Electron ◽

Composition Of Products

AbstractBaCO3 nanoparticles with different morphologies including needle-like, rod-like, bird's nest-like and flower-like have been successfully synthesized by the microwave homogeneous precipitation method using BaCl2·2H2O, NaOH and (NH2)2CO as raw materials with the help of different guide reagents, such as citric acid (CA), sodium triphosphate (STPP) and ethylene diamine tetraacetic acid (EDTA). Their phases and morphologies were characterized by X-ray powder diffraction (XRD) and scanning electron microscopy (SEM), respectively. The characterization results show that different guide reagents have little effect on the phase structure and composition of products while they play significant roles in determining the morphology of products. All the synthesized BaCO3 nanoparticles have typical orthorhombic structures that are well-crystallized.

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Preparation and Optical Properties of Y2O3:Tb3+ Nanoballs

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2016.11829 ◽

2016 ◽

Vol 16 (4) ◽

pp. 3886-3889 ◽

Cited By ~ 3

Author(s):

Hongquan Yu ◽

Ye Qi ◽

Yanbo Wu ◽

Jinsu Zhang ◽

Baojiu Chen

Keyword(s):

Optimum Concentration ◽

Precipitation Method ◽

Homogeneous Precipitation ◽

Particle Sizes ◽

Photoluminescence Spectra ◽

X Ray Diffraction ◽

X Ray ◽

Homogeneous Precipitation Method ◽

Scanning Electron Microcopy ◽

Scanning Electron

Y2O3:Tb3+ nanoballs were synthesized via the urea homogeneous precipitation method (UPM). The resulting Y2O3:Tb3+ phosphors were characterized by X-ray diffraction (XRD), scanning electron microscopy, ultraviolet-visible (UV-vis) absorption spectra, and general photoluminescence spectra. The particle sizes estimated using X-ray diffractometry and scanning electron microcopy were about 50–200 nm. The emission intensity of the Y2O3:Tb3+ was low when the doping concentrations of Tb3+ were higher. The optimum concentration of Tb3+ for synthesis of Y2O3:Tb3+ nanocrystals is 1%.

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Influence of Synthesis Technics and Additives on Cerium Ion Compound Valence

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.335-336.1051 ◽

2011 ◽

Vol 335-336 ◽

pp. 1051-1055

Author(s):

Yan Mei ◽

Chuan Xia ◽

Xiao Li Chen ◽

Zuo Ren Nie

Keyword(s):

Coupling Method ◽

Precipitation Method ◽

Urea Solution ◽

Homogeneous Precipitation ◽

State Change ◽

X Ray Diffraction ◽

X Ray ◽

Homogeneous Precipitation Method ◽

Transmission Electron ◽

Cerium Ion

In the system of Ce(NO3)3·6H2O and urea solution during homogeneous precipitation method, hydrothermal homogeneous precipitation coupling method and homogeneous precipitation method with additive, X-ray diffraction (XRD) and transmission electron microscope (TEM) were used to study and characterize the product structures and morphologies. The outer electron configurations and the energy conservation theory were used to analyze the reasons for stability of products and valence state change of cerium ions. The results showed that synthesis technics and additives had a great effect on the cerium ion compound valence. The products were orthorhombic Ce2O(CO3)2·H2O with Valence Ш and orthorhombic CeO(CO3)2·H2O with valence Ⅵ by using homogeneous precipitation method and hydrothermal homogeneous precipitation coupling method, respectively. If an additive (triethanolamine or triethylamine) was added into the homogeneous precipitation system, the products changed into a mixture of orthorhombic CeO(CO3)2·H2O with Valence Ⅵ and cubic CeO2 with valence Ⅳ. It showed that triethanolamine or triethylamine had strong oxidizing properties and played a catalyst role in the reaction.

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Synthesis and Characterization of Hexagonal Prismatic Ca10(PO4)6(OH)2 Prepared by Homogeneous Precipitation Method

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.391-392.1239 ◽

2011 ◽

Vol 391-392 ◽

pp. 1239-1243

Author(s):

Zhan Hui Zhang ◽

Zhi Liang Huang ◽

Jian Qiu Li ◽

Ru An Chi ◽

Yue Hua Hu ◽

...

Keyword(s):

Growth Process ◽

Crystal Morphology ◽

Precipitation Method ◽

Synthesis And Characterization ◽

Hexagonal Prism ◽

Homogeneous Precipitation ◽

X Ray Diffraction ◽

X Ray ◽

Homogeneous Precipitation Method

Hexagonal prismatic hydroxyapatite (Ca10(PO4)6(OH)2, HAP) was successfully prepared by a homogeneous precipitation method. The products were characterized by X-ray diffraction, Fourier transform infrared spectrum, and scanning electron microscope. The growth process of the hexagonal prism was surveyed in detail based on the effects of the reaction time on the phase composition and the crystal morphology.

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Synthesis and Characterization of Nanocrystalline Ceria Powder through Homogeneous Precipitation Method

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.557-559.567 ◽

2012 ◽

Vol 557-559 ◽

pp. 567-571

Author(s):

Jin Liang ◽

Hong Chen

Keyword(s):

Particle Size ◽

Orthogonal Experiment ◽

Fluorite Structure ◽

Precipitation Method ◽

Homogeneous Precipitation ◽

X Ray Diffraction ◽

X Ray ◽

Homogeneous Precipitation Method ◽

Nanocrystalline Ceria

Nanocrystalline ceria powder was prepared through homogeneous precipitation method, orthogonal experiment was designed to figure out the most important factor that influence the particle size of the resultant and the optimum condition. X-ray diffraction revealed that the as-prepared nanoscale ceria powder had cubic fluorite structure, TEM image showed that the ceria powder was weakly agglomerated with a particle size of about 10 nm.

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Luminescence Properties of Europium-Doped Yttrium Oxides Derived from Their Dodecylsulfate-Templated Mesostructure and Nanotube Forms

MRS Proceedings ◽

10.1557/proc-775-p3.2 ◽

2003 ◽

Vol 775 ◽

Cited By ~ 2

Author(s):

Tsuyoshi Kijima ◽

Kenichi Iwanaga ◽

Tomomi Hamasuna ◽

Shinji Mohri ◽

Mitsunori Yada ◽

...

Keyword(s):

Room Temperature ◽

Broad Band ◽

Concentration Quenching ◽

Precipitation Method ◽

Homogeneous Precipitation ◽

Bulk Materials ◽

Main Band ◽

Homogeneous Precipitation Method ◽

Order Of Magnitude ◽

Weak Luminescence

AbstractEuropium-doped hexagonal-mesostructured and nanotubular yttrium oxides templated by dodecylsulfate species as well as surfactant free bulk oxides were synthesized by the homogeneous precipitation method. All the as grown nanostructured or bulk materials with amorphous or poorly crystalline frameworks showed weak luminescence bands at room temperature. On calcination at 1000°C these materials were converted into highly crystalline yttrium oxides, resulting in a total increase in intensity of all the bands by one order of magnitude. In the hexagonal-mesostructured system, the main band due to the 5D0-7F2 transition for the calcined phases showed a sharp but asymmetrical multiplet splitting indicating multiple Eu sites. Concentration quenching was found at a Eu content of 3 mol% or above for these phases. In contrast, the main emission for the calcined solids in the nanotubular system occurred as poorly resolved broad band and the intensity of the main band at higher Eu content was significantly enhanced compared with those for the other two systems.

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