Mechanical alloys Mg-Me (Me: Ti, Fe, Ni, Al) & Mg-Me1-Me2(Ме1:Al, Me2: Ti, Fe, Ni) with low resistance and improved kinetics of hydrogenation/dehydrogenation for hydrogen storage applications

Changes in MgH2 decomposition kinetics were investigated in dependence on complex doping of MgH2 by Al, Ti, Ni, and Fe. Reactive mechanochemical alloying method (RMA) was applied in the temperature descending regime. It was found that addition of Al+Ni+Ti, Al+Ti, Fe+Ti (see below) and Al+Fe elements combinations led to a lower thermal stability and, consequently, to a lowering of the temperature of hydrogen desorption onset. Whereas desorption began at temperature of 320 °C from the pure MgH2, the aditions of Al, Ni, Ti and Fe lowered the start of the desorption down to 250°C (at hydrogen pressure 0.1 MPa in the reactor). Very fast desorption kineticsprecize at 300 0C and PH 2= 0.1 MPa were observed for Mg+Me mixture in comparison with the pure Mg. Sorption capacity of investigated mechanically-alloyed composites varied from 5 to 6.5 wt. % H2. The tested materials showed a high potential as hydrogen storage alloys especially for stationary application.

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The Influence of Complex Doping on Kinetics of Decomposition and Thermal Stability of Mg-Based Mechanical Alloys

Фізика і хімія твердого тіла ◽

10.15330/pcss.20.4.406-415 ◽

2019 ◽

Vol 20 (4) ◽

pp. 406-415

Author(s):

O.G. Ershova ◽

V.D. Dobrovolsky ◽

Yu.M. Solonin

Keyword(s):

Thermal Stability ◽

Thermal Desorption Spectroscopy ◽

Hydrogen Desorption ◽

Hydride Phase ◽

Hydrogen Storage Alloys ◽

Reactive Grinding ◽

Kinetics Of ◽

Reactive Mechanical Alloying ◽

Thermal Stability Of ◽

Complex Doping

Mechanical alloys (MАs) were synthesized by the method of reactive mechanical alloying. At a hydrogen pressure of 0.1 MPa, with the use of thermal desorption spectroscopy, the thermal stability, the kinetics of hydrogen desorption from the hydride phase MgH2 of the obtained MAs were studied. It has been established that the complex doping by of Fe, Si, Ti, leads to a significant improvement in the of hydrogen desorption from the hydride phase MgH2 of MA synthesized by the RMA. Hydrogen capacity CH of MА after reactive grinding for 20 h. was found to be equal to 5.7 % wt. Due to this alloying, the decrease in the thermodynamic stability of MgH2 is not established. The tested materials showed a high potential as hydrogen storage alloys especially for stationary application.

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Thermal Stability and Decomposition Kinetics of 1-Alkyl-2,3-Dimethylimidazolium Nitrate Ionic Liquids: TGA and DFT Study

Materials ◽

10.3390/ma14102560 ◽

2021 ◽

Vol 14 (10) ◽

pp. 2560

Author(s):

Jianwen Meng ◽

Yong Pan ◽

Fan Yang ◽

Yanjun Wang ◽

Zhongyu Zheng ◽

...

Keyword(s):

Thermal Stability ◽

Density Functional Theory ◽

Ionic Liquids ◽

Density Functional ◽

Density Functional Theory Calculations ◽

Nitrogen Atmosphere ◽

Decomposition Kinetics ◽

Heating Rates ◽

Functional Theory ◽

Kinetics Of

The thermal stability and decomposition kinetics analysis of 1-alkyl-2,3-dimethylimidazole nitrate ionic liquids with different alkyl chains (ethyl, butyl, hexyl, octyl and decyl) were investigated by using isothermal and nonisothermal thermogravimetric analysis combined with thermoanalytical kinetics calculations (Kissinger, Friedman and Flynn-Wall-Ozawa) and density functional theory (DFT) calculations. Isothermal experiments were performed in a nitrogen atmosphere at 240, 250, 260 and 270 °C. In addition, the nonisothermal experiments were carried out in nitrogen and air atmospheres from 30 to 600 °C with heating rates of 5, 10, 15, 20 and 25 °C/min. The results of two heating modes, three activation energy calculations and density functional theory calculations consistently showed that the thermal stability of 1-alkyl-2,3-dimethylimidazolium nitrate ionic liquids decreases with the increasing length of the alkyl chain of the substituent on the cation, and then the thermal hazard increases. This study could provide some guidance for the safety design and use of imidazolium nitrate ionic liquids for engineering.

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Thermal Stability and Decomposition Kinetics of AgO Submicron Particles Prepared by Potassium Persulfate Oxidation

Materials Science ◽

10.5755/j01.ms.24.1.17052 ◽

2018 ◽

Vol 24 (1) ◽

Cited By ~ 1

Author(s):

Hui FENG ◽

Wenning SHEN ◽

Lajun FENG ◽

Ali LEI ◽

Yanfeng GE

Keyword(s):

Thermal Stability ◽

Decomposition Kinetics ◽

Potassium Persulfate ◽

Submicron Particles ◽

Persulfate Oxidation ◽

Kinetics Of

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Electrochemical Behaviour of Some Mechanically Alloyed Mg — Ni-Based Amorphous Hydrogen Storage Alloys*

Zeitschrift für Physikalische Chemie ◽

10.1524/zpch.1994.183.part_1_2.379 ◽

1994 ◽

Vol 183 (Part_1_2) ◽

pp. 379-384 ◽

Cited By ~ 173

Author(s):

Yong-quan Lei ◽

Yu-ming Wu ◽

Quan-ming Yang ◽

Jing Wu ◽

Qi-dong Wang

Keyword(s):

Hydrogen Storage ◽

Electrochemical Behaviour ◽

Hydrogen Storage Alloys ◽

Mechanically Alloyed

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Preparation and Hydrogen Storage Kinetics of Nanocrystalline and Amorphous Mg20Ni8M2 (M=Cu, Co) Alloys

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.586.50 ◽

2012 ◽

Vol 586 ◽

pp. 50-57

Author(s):

Yang Huan Zhang ◽

Tai Yang ◽

Hong Wei Shang ◽

Guo Fang Zhang ◽

Xia Li ◽

...

Keyword(s):

Hydrogen Storage ◽

Melt Spinning ◽

Nanocrystalline Structure ◽

Hydrogen Desorption ◽

Amorphous Structure ◽

Saturation Ratio ◽

Cu Alloy ◽

Nanocrystalline And Amorphous ◽

Kinetics Of ◽

Co Alloys

In order to obtain a nanocrystalline and amorphous structure, the Mg20Ni8M2 (M=Cu, Co) hydrogen storage alloys were fabricated by the melt spinning technology. The microstructures of the alloys were characterized by XRD, SEM and HRTEM. The effects of the melt spinning on the hydriding and dehydriding kinetics of the alloys were investigated. The results indicate that the as-spun (M=Cu) alloys hold an entire nanocrystalline structure even if the limited spinning rate is applied, while the as-spun (M=Co) alloys display a nanocrystalline and amorphous structure as the spinning rate grows to 30 m/s, suggesting that the substitution of Co for Ni facilitates the glass formation in the Mg2Ni-type alloy. The melt spinning remarkably improves the gaseous hydriding and dehydriding kinetics of the alloys. As the spinning rate grows from 0 (As-cast was defined as the spinning rate of 0 m/s) to 30 m/s, the hydrogen absorption saturation ratio ( ) is enhanced from 56.72% to 92.74% for the (M=Cu) alloy and from 80.43% to 94.38% for the (M=Co) alloy. The hydrogen desorption ratio ( ) is raised from14.89% to 40.37% for the (M=Cu) alloy and from 24.52% to 51.67% for the (M=Co) alloy.

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Preparation of La-Mg-Ni Hydrogen Storage Composite Alloys by Mechanical Alloying

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.807-809.2707 ◽

2013 ◽

Vol 807-809 ◽

pp. 2707-2712 ◽

Cited By ~ 1

Author(s):

Shi Jian Yan ◽

Xin Wei Zou ◽

Min Gang Zhang

Keyword(s):

Hydrogen Storage ◽

Mechanical Alloying ◽

Ball Milling ◽

Metal Powder ◽

Hydrogen Desorption ◽

Hydrogen Atmosphere ◽

Hydrogen Storage Alloys ◽

Milling Parameters ◽

Multi Phase ◽

Mg Content

LaNi5-xwt%Mg hydrogen storage alloys with different Mg content were made from pure La, Mg and Ni metal powder by mechanical alloying, selecting appropriate ball-milling parameters in 0.4MPa hydrogen atmosphere. The characterizations for hydrogen storage alloy show that a multi-phase alloy composed of MgH2, LaH3, Mg2NiH4 and Ni was obtained, the alloy have two hydrogen desorption temperature range, and the alloy with 25wt% Mg content can desorb hydrogen up to 4.02wt%.

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