Preparation and Hydrogen Storage Properties of Mg-Ni-B BCC Alloys

Mg-Ni-B system alloys were prepared by the mechanical alloying (MA) method. Body centered cubic (BCC) structure alloys are obtained in some of the Mg-Ni-B compositions after the starting mixtures of raw elements were ball milled for 200 h. Mg50Ni45B5 and Mg48Ni48B4 alloys after ball milling are with single BCC structure, which is confirmed by electron diffraction patterns. From the results of X-ray diffraction and transmission electron microscope, the crystallite size of the alloys is calculated into nanometer scale. Mg50Ni45B5 and Mg48Ni48B4 BCC alloys can absorb hydrogen at 373 K with higher rate than Mg50Ni50 alloy prepared in the same conditions. And these two samples can reach a hydrogen absorption capacity of 1.94 and 1.93 mass%, respectively at 373 K without any activation process.

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Millable Polyurethane/Organoclay Nanocomposites: Preparation, Characterization, and Properties

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2007.134 ◽

2007 ◽

Vol 7 (2) ◽

pp. 634-640 ◽

Cited By ~ 7

Author(s):

M. Siliani ◽

M. A. López-Manchado ◽

J. L. Valentín ◽

M. Arroyo ◽

A. Marcos ◽

...

Keyword(s):

Barrier Properties ◽

Substantial Improvement ◽

Nanometer Scale ◽

X Ray Diffraction ◽

Transformation Techniques ◽

Covalent Bonds ◽

X Ray ◽

Transmission Electron ◽

Organically Modified ◽

Diffraction Patterns

Novel millable polyurethane (PU)/organoclay nanocomposites have been successfully prepared by conventional transformation techniques. One natural (C6A) and two organically modified (C15A and C30B) montmorillonites have been used as clays for preparing PU nanocomposites. The optimum dispersion of nanofiller at a nanometer scale in PU matrix was confirmed by X-ray diffraction patterns and transmission electron microscopy. A substantial improvement of the PU properties by addition of only a small amount of organoclay was observed. It is worthy to note that the organoclays show a different interfacial interaction with the PU matrix, which was reflected in different macroscopic properties. Thus, C30B organoclay seems to react with PU chains to form covalent bonds, while C15Aonly interacts physically with PU chains. Mechanical and barrier properties are analyzed.

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Microwave Synthesis of MOFs/Graphene Oxide Composites and Hydrogen Storage Properties

Materials Science Forum ◽

10.4028/www.scientific.net/msf.852.835 ◽

2016 ◽

Vol 852 ◽

pp. 835-840 ◽

Cited By ~ 1

Author(s):

Tian Bao Yang ◽

Li Xian Sun ◽

Fen Xu ◽

Zi Qiang Wang

Keyword(s):

Electron Microscopy ◽

Graphene Oxide ◽

Hydrogen Storage ◽

Parent Material ◽

X Ray Diffraction ◽

Hydrogen Storage Properties ◽

Transmission Electron ◽

Metal Organic ◽

Oxide Composites ◽

Storage Properties

Metal-organic frameworks (MOFs: copper containing CuBTC)-graphene oxide (GO) composite (CG) was synthesized using microwave heating. The parent material and the composite were characterized by X-ray diffraction (XRD), thermogravimetric analysis (TGA), nitrogen sorption, scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), Fourier transform infrared spectroscopy (HRTEM) and Raman spectroscopy. Then their hydrogen storage properties were systematically tested. The composite material CG shows a remarkable H2 capacity up to 2.43 wt% (28.6% increases vs. CuBTC) and higher surface area and pore volume compared to the neat CuBTC. And the particle size of CG is down to nanometer scale.

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Synthesis of MIL-125/Graphene Oxide Composites and Hydrogen Storage Properties

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.727.683 ◽

2017 ◽

Vol 727 ◽

pp. 683-687 ◽

Cited By ~ 2

Author(s):

Tian Bao Yang ◽

Li Xian Sun ◽

Fen Xu ◽

Zi Qiang Wang ◽

Yong Jin Zou ◽

...

Keyword(s):

Electron Microscopy ◽

Graphene Oxide ◽

Hydrogen Storage ◽

Parent Material ◽

X Ray Diffraction ◽

Hydrogen Storage Properties ◽

Transmission Electron ◽

Metal Organic ◽

Ft Ir ◽

Storage Properties

Metal-organic frameworks (MOFs: MIL-125)-graphene oxide (GO) composite (MO) was synthesized by solvothermal method. All the materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), high resolution transmission electron microscopy (HRTEM), Fourier transform infrared spectroscopy (FT-IR) and Raman spectroscopy. Then their hydrogen storage properties were systematically tested under 1 bar and 77K. The composite material MO-1 possesses higher surface area than the parent material MIL-125 and shows a remarkable H2 capacity up to 2.5 wt% (38% increases vs. MIL-125).

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Hydrogen storage properties of mechanically alloyedMg–8 mol% LaNi0.5 composite

Journal of Materials Research ◽

10.1557/jmr.2004.0396 ◽

2004 ◽

Vol 19 (10) ◽

pp. 2871-2876 ◽

Cited By ~ 14

Author(s):

Qian Li ◽

Qin Lin ◽

Kuo-Chih Chou ◽

Li-Jun Jiang ◽

Feng Zhan

Keyword(s):

Hydrogen Storage ◽

Mechanical Alloying ◽

X Ray Diffraction ◽

Equilibrium Pressure ◽

Hydrogen Storage Properties ◽

X Ray ◽

Transmission Electron ◽

Lower Temperature ◽

Material Preparation ◽

Storage Properties

A new nano-ternary Mg–8 mol% LaNi0.5 was prepared by melted and subsequent mechanical alloying technique for hydrogen storage. It was found from our experiments that, this kind of alloy had superior hydriding/dehydriding characteristics in comparison with conventional materials for hydrogen storage. It possessed large hydrogen capacity at a lower temperature, which could absorb 4.55–7.01 mass% H under 3 MPa hydrogen pressure and desorb 4.40–6.90 mass% H under 0.0133 MPa in 600 s above 423 K without any activation requirement drawn from our pressure-composition isotherm and kinetic experiments. Through the x-ray diffraction and transmission electron microscopy experiments, we further found that these superior characteristics could be attributed to the multiphase structure and a catalytic effect of LaH3 and Mg2Ni that were formed in the material preparation of mechanical alloying process. Finally, based on these data the relationships between equilibrium pressure of hydrogen and temperature were obtained, they were lgp(0.1 MPa) = −3985/T + 7.188(553 K ⩽ T ⩽ 573K) for hydriding and lgp(0.1 MPa) = −3804/T + 6.770 (553 K ⩽ T ⩽ 573 K) for dehydriding.

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Microstructure and properties of nano-laminated Y3Si2C2 ceramics fabricated via in situ reaction by spark plasma sintering

Journal of Advanced Ceramics ◽

10.1007/s40145-021-0459-0 ◽

2021 ◽

Vol 10 (3) ◽

pp. 578-586

Author(s):

Lin-Kun Shi ◽

Xiaobing Zhou ◽

Jian-Qing Dai ◽

Ke Chen ◽

Zhengren Huang ◽

...

Keyword(s):

Spark Plasma Sintering ◽

Atomic Scale ◽

Max Phase ◽

X Ray Diffraction ◽

Selected Area Electron Diffraction ◽

Plasma Sintering ◽

Transmission Electron ◽

Spark Plasma ◽

Diffraction Patterns

AbstractA nano-laminated Y3Si2C2 ceramic material was successfully synthesized via an in situ reaction between YH2 and SiC using spark plasma sintering technology. A MAX phase-like ternary layered structure of Y3Si2C2 was observed at the atomic-scale by high resolution transmission electron microscopy. The lattice parameters calculated from both X-ray diffraction and selected area electron diffraction patterns are in good agreement with the reported theoretical results. The nano-laminated fracture of kink boundaries, delamination, and slipping were observed at the tip of the Vickers indents. The elastic modulus and Vickers hardness of Y3Si2C2 ceramics (with 5.5 wt% Y2O3) sintered at 1500 °C were 156 and 6.4 GPa, respectively. The corresponding values of thermal and electrical conductivity were 13.7 W·m-1·K-1 and 6.3×105 S·m-1, respectively.

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Cetyltrimethylammonium bromide- and ethylene glycol-assisted preparation of mono-dispersed indium oxide nanoparticles using hydrothermal method

Chemical Papers ◽

10.2478/s11696-014-0543-9 ◽

2014 ◽

Vol 68 (8) ◽

Cited By ~ 5

Author(s):

Selvakumar Dhanasingh ◽

Dharmaraj Nallasamy ◽

Saravanan Padmanapan ◽

Vinod Padaki

Keyword(s):

Ethylene Glycol ◽

Hydrothermal Method ◽

Indium Oxide ◽

Cetyltrimethylammonium Bromide ◽

Oxide Nanoparticles ◽

X Ray Diffraction ◽

Hydrothermal Conditions ◽

X Ray ◽

Transmission Electron ◽

Diffraction Patterns

AbstractThe influence of cetyltrimethylammonium bromide and ethylene glycol on the size and dispersion of indium oxide nanoparticles prepared under hydrothermal conditions was investigated. The precursor compound, indium hydroxide, obtained by the hydrothermal method in the absence as well as the presence of cetyltrimethylammonium bromide, was converted to indium oxide by sintering at 400°C. The formation of nanoscale indium oxide upon sintering was ascertained by the characteristic infrared adsorption bands and X-ray diffraction patterns of indium oxide. Transmission electron microscopy and band gap values confirmed that the cetyltrimethylammonium bromide facilitated the formation of indium oxide nanoparticles smaller in size and narrower in distribution than those prepared without the assistance of cetyltrimethylammonium bromide.

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Facile Refluxing Synthesis of Hydroxyapatite Nanoparticles

Australian Journal of Chemistry ◽

10.1071/ch14642 ◽

2015 ◽

Vol 68 (8) ◽

pp. 1293 ◽

Cited By ~ 5

Author(s):

Pakvipar Chaopanich ◽

Punnama Siriphannon

Keyword(s):

Crystallite Size ◽

Reaction Times ◽

Single Step ◽

Hydroxyapatite Nanoparticles ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Aqueous Mixture ◽

Diffraction Patterns ◽

Microscopy Images

Hydroxyapatite (HAp) nanoparticles were successfully synthesized from an aqueous mixture of Ca(NO3)2·4H2O and (NH4)2HPO4 by a facile single-step refluxing method using polystyrene sulfonate (PSS) as a template. The effects of reaction times, pH, and PSS concentration on the HAp formation were investigated. It was found that the crystalline HAp was obtained under all conditions after refluxing the precursors for 3 and 6 h. The longer refluxing time, the greater the crystallinity and the larger the crystallite size of the HAp nanoparticles. The HAp with poor crystallinity was obtained at pH 8.5; however, the well-crystallized HAp was obtained when reaction pH was increased to 9.5 and 10.5. In addition, the X-ray diffraction patterns revealed that the presence of PSS template caused the reduction of HAp crystallite size along the (002) plane from 52.6 nm of non-template HAp to 43.4 nm and 41.4 nm of HAp with 0.05 and 0.2 wt-% PSS template, respectively. Transmission electron microscopy images of the synthesized HAp revealed the rod-shaped crystals of all samples. The synthesized HAp nanoparticles were modified by l-aspartic acid (Asp) and l-arginine (Arg), having negative and positive charges, respectively. It was found that the zeta potential of HAp was significantly changed from +5.46 to –24.70 mV after modification with Asp, whereas it was +4.72 mV in the Arg-modified HAp. These results suggested that the negatively charged amino acid was preferentially adsorbed onto the synthesized HAp surface.

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Appropriate Conditions for Preparation of Nanosized WO3 through High-Energy-Milling

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.194-196.665 ◽

2011 ◽

Vol 194-196 ◽

pp. 665-668

Author(s):

Chun Huan Chen ◽

Rui Ming Ren

Keyword(s):

Grain Size ◽

Milling Time ◽

Rotation Speed ◽

Processing Parameters ◽

High Energy ◽

Charge Ratio ◽

Activation Process ◽

X Ray Diffraction ◽

High Energy Milling ◽

Transmission Electron

In order to synthesize WC-Co nanopowders through an integrated mechanical and thermal activation process, WO3-Co2O3-C nanopowders need to be obtained first. It is critical how to obtain the WO3-Co2O3-C nanopowders efficiently. The effect of processing parameters on the grain size during high-energy-milling of WO3-Co2O3-C mixed powders was studied via X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results show that the grain size of reactants can be effectively decreased with increasing the milling time, rotation speed, and charge ratio. After a certain time milling, both WO3 and C powders achieve nano-level in grain size and mixed homogeneously. The appropriate milling parameters for fabricating nanosized WO3+C+Co2O3 powders are suggested to be 4 to 8 hours of milling time, 400 RPM of rotation speed, and 40:1 to 60:1 of charge ratio.

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A Chemical Solution Route to Rapid Synthesis of Homogeneous Bi100−xSbx Alloys Nanoparticles at Room Temperature

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2007.151 ◽

2007 ◽

Vol 7 (2) ◽

pp. 525-529 ◽

Cited By ~ 3

Author(s):

Bo Zhou ◽

Jun-Jie Zhu

Keyword(s):

Room Temperature ◽

Raw Materials ◽

X Ray Diffraction ◽

X Ray ◽

Selected Area Electron Diffraction ◽

Transmission Electron ◽

Solution Route ◽

Diffraction Patterns ◽

Co Reduction ◽

Chemical Solution Route

A chemical co-reduction route in aqueous solution was developed to synthesize Bi100−xSbx alloys at room temperature. The hydrolyses of Bi(III) and Sb(III) were effectively avoided by selecting proper raw materials and coordinator. X-ray diffraction analysis indicated that the as-prepared Bi100−xSbx alloys were homogeneous and phase-pure, and the Bi/Sb ratios in the alloys were very close to those in the aqueous solutions. The transmission electron microscope observation showed that the as-prepared Bi100−xSbx (x = 0∼100) alloys were particles with a size of tens of nanometers. The selected area electron diffraction patterns confirmed the high crystallinity, the homogeneousness, and the composition controllability of as-prepared alloys. All these characters and the nanometer-scaled size of the alloys are believed to be beneficial to the thermoelectric property of the Bi100−xSbx alloys.

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