Influence of hydrothermal synthesis conditions on size, morphology and colloidal properties of Hematite nanoparticles

2015 ◽  
Vol 2 ◽  
pp. 19-27 ◽  
Author(s):  
Claudio Colombo ◽  
Giuseppe Palumbo ◽  
Erika Di Iorio ◽  
Xin Song ◽  
Zhaoxia Jiang ◽  
...  
Keyword(s):  
Hydrothermal Synthesis ◽  
Hematite Nanoparticles ◽  
Synthesis Conditions ◽  
Colloidal Properties

Preparation of Silicalite-1 Membranes with Seeding Method and its Separation Performance for Low Ethanol/Water Mixture

2013 ◽  
Vol 807-809 ◽  
pp. 591-595
Author(s):  
Hong Liang Chen ◽  
Ji Song Yang ◽  
Yan Wang ◽  
Hui Ying Li ◽  
Xin Xin Li ◽  
...  
Keyword(s):  
Hydrothermal Synthesis ◽  
Separation Factor ◽  
High Performance ◽  
Separation Performance ◽  
Water Mixture ◽  
Synthesis Conditions ◽  
Seeding Method

High performance silicalite-1 membranes were successfully synthesized on silica tubes by seeding method after filling the tubes with water and glycerol mixtures. After seeding the silica tubes with 200 nm seeds, all the silicalite-1 membranes show acceptable separation performance towards ethanol/water mixture after 4-12 h hydrothermal synthesis, and the highest flux of membrane with 8 h hydrothermal synthesis reaches about 0.98 kg/m2.h and the separation factor reaches about 60 towards 3 wt.% ethanol/water mixture. This result shows that the as-synthesized silicalite-1 membrane can concentrate the ethanol from 3% to about 65%, and the ethanol can be obtained over 600 g/m2.h by using the silicalite-1 membrane, which shows that seeding method and suitable control of synthesis conditions is possible for preparing high-performance silicalite-1 membranes.

scholarly journals Influence of the Al/Ge Ratio on the Structure and Self-Organization of Anisometric Imogolite Nanotubes

Crystals ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1094
Author(s):  
Erwan Paineau ◽  
Pascale Launois
Keyword(s):  
Aspect Ratio ◽  
Liquid Crystalline ◽  
Functional Materials ◽  
Slight Modification ◽  
Self Organization ◽  
Molar Ratio ◽  
Stimuli Responsive ◽  
Synthesis Conditions ◽  
Colloidal Properties ◽  
R Ratio

Synthetic imogolite-like nanotubes (INT) with well-defined diameters represent a considerable opportunity for the development of advanced functional materials. Recent progress has made it possible to increase their aspect ratio and unique self-organization properties were evidenced. We suggest that slight modification of the synthesis conditions may drastically affect the resulting liquid-crystalline properties. In this work, we investigate how the precursor’s [Al]/[Ge] molar ratio (R’) impacts the morphology and the colloidal properties of aluminogermanate INTs by combining a multi-scale characterization. While only double-walled nanotubes are found for R’ ≥ 1.8, the presence of single-walled nanotubes occurs when the ratio is lowered. Except for the lowest R’ ratio investigated (R’ = 0.66), all synthetic products present one-dimensional shapes with a high aspect ratio. Small-angle X-ray scattering experiments allow us to comprehensively investigate the colloidal properties of the final products. Our results reveal that a liquid-crystalline hexagonal columnar phase is detected down to R’ = 1.33 and that it turns into a nematic arrested phase for R’ = 0.90. These results could be useful for the development of novel stimuli-responsive nanocomposites based-on synthetic imogolite nanotubes.

The effect of reaction medium and hydrothermal synthesis conditions on morphological parameters and thermal behavior of calcium phosphate nanoparticles

2021 ◽  
Vol 47 (2) ◽  
pp. 2809-2821 ◽  
Author(s):  
Evgeniya A. Syukkalova ◽  
Anastasia V. Sadetskaya ◽  
Natalya D. Demidova ◽  
Natalia P. Bobrysheva ◽  
Mikhail G. Osmolowsky ◽  
...  
Keyword(s):  
Hydrothermal Synthesis ◽  
Calcium Phosphate ◽  
Thermal Behavior ◽  
Reaction Medium ◽  
Morphological Parameters ◽  
Synthesis Conditions ◽  
Calcium Phosphate Nanoparticles

scholarly journals Adjusting the Magnetic Properties of ZrO2:Mn Nanocrystals by Changing Hydrothermal Synthesis Conditions

2018 ◽  
Vol 4 (2) ◽  
pp. 28 ◽  
Author(s):  
Izabela Kuryliszyn-Kudelska ◽  
Witold Dobrowolski ◽  
Monika Arciszewska ◽  
Artur Małolepszy ◽  
Leszek Stobinski ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Hydrothermal Synthesis ◽  
Synthesis Conditions

Synthesis and characterization of the lead borate Pb6B12O21(OH)6

2016 ◽  
Vol 71 (8) ◽  
pp. 925-933 ◽  
Author(s):  
Sandra Schönegger ◽  
Teresa S. Ortner ◽  
Klaus Wurst ◽  
Gunter Heymann ◽  
Hubert Huppertz
Keyword(s):  
Crystal Structure ◽  
Hydrothermal Synthesis ◽  
Potassium Nitrate ◽  
Lattice Parameters ◽  
Synthesis And Characterization ◽  
Lead Borate ◽  
Hydrothermal Conditions ◽  
Organic Reagents ◽  
Synthesis Conditions

AbstractA lead borate with the composition Pb6B12O21(OH)6 was synthesized through a hydrothermal synthesis, using lead metaborate in combination with sodium nitrate and potassium nitrate. The compound crystallizes in the trigonal, non-centrosymmetric space group P32 (no. 145) with the lattice parameters a = 1176.0(4), c = 1333.0(4) pm, and V = 0.1596(2) nm3. Interestingly, the data of Pb6B12O21(OH)6 correct the structure of a literature known lead borate with the composition “Pb6B11O18(OH)9”. For the latter compound, nearly identical lattice parameters of a = 1176.91(7) and c = 1333.62(12) pm were reported, possessing a crystal structure, in which the localization and refinement of one boron atom was obviously overlooked. The structure of Pb6B12O21(OH)6 is built up from trigonal planar BO3 and tetrahedral BO4 groups forming complex chains. The Pb2+ cations are located between neighboring polyborate chains. The here reported compound Pb6B12O21(OH)6 and “Pb6B11O18(OH)9” were, however, produced under different synthesis conditions. While “Pb6B11O18(OH)9” was synthesized via a hydrothermal synthesis including ethylenediamine and acetic acid, the here reported lead borate Pb6B12O21(OH)6 could be obtained under moderate hydrothermal conditions (240°C) without the addition of organic reagents.

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