Pd–Ru electrodeposits with high hydrogen absorption capacity

2012 ◽  
Vol 20 ◽  
pp. 175-177 ◽  
Author(s):  
K. Hubkowska ◽  
M. Łukaszewski ◽  
A. Czerwiński
Keyword(s):  
Hydrogen Absorption ◽  
Absorption Capacity ◽  
High Hydrogen

Hydrides Formed in ZrCo2 – Based Intermetallic Compounds Under High Hydrogen Pressure / Wodorki Wytwarzane Pod Wysokimi Cisnieniami Wodoru Ze Zwiazków Miedzymetalicznych Na Osnowie ZrCo2

2013 ◽  
Vol 58 (1) ◽  
pp. 223-226 ◽  
Author(s):  
S.M. Filipek ◽  
Ru-Shi Liu ◽  
N. Kuriyama ◽  
N. Takeichi ◽  
H. Tanaka ◽  
...  
Keyword(s):  
Intermetallic Compounds ◽  
Hydrogen Absorption ◽  
High Stability ◽  
Hydrogen Pressure ◽  
Absorption Capacity ◽  
Partial Substitution ◽  
Desorption Rate ◽  
High Hydrogen ◽  
High Hydrogen Pressure

The hydrides of zirconium based pseudobinary alloys Zr(Co1-xTx)2, (T = Fe, V or Cr) and Zr1-xRxCo2 (R = Y, La, Pr) were synthesized under 1.2 GPa of hydrogen pressure. It was revealed that partial substitution of cobalt by V, Cr or Fe increases hydrogen absorption capacity and stability of derived hydrides. Especially, it was found that ZrCo1:8V0:2 alloy exposed to high hydrogen pressure can absorb 50% more hydrogen than pure ZrCo2 and the hydride ZrCo1:8V0:2Hy has surprisingly high stability. Substitution of zirconium by Y, La or Pr in ZrCo2 alloys improved hydrogen absorption but hydrides derived from La and Pr substituted alloys were less stable than ZrCo2H2. Only for Zr0:7Y0:3Co0:2Hy the hydrogen absorption was higher and desorption rate markedly smaller comparing ZrCo2H2.

Magnesium Hydride: From the Laboratory to the Tank

2007 ◽  
Vol 62 (7) ◽  
pp. 907-914 ◽  
Author(s):  
Jean-Gabriel Roquefere ◽  
Jean-Louis Bobet
Keyword(s):  
Hydrogen Absorption ◽  
Hydrogenation Reaction ◽  
Extensive Study ◽  
Absorption Capacity ◽  
Research Groups ◽  
Mechanical Grinding ◽  
Absorption Properties ◽  
High Hydrogen ◽  
Magnesium Metal ◽  
Recent Developments

Abstract Magnesium metal is under extensive study for its high hydrogen absorption capacity. The main results obtained by the authors, going from the effects of ‘reactive mechanical grinding’ to the addition of nano oxides or to the deposition of nanoparticles are reported and discussed. The absorption properties are compared with the results of other research groups. An improvement of kinetics has been achieved and the mechanisms of the hydrogenation reaction is almost fully understood, but the effects of catalysts are still subject to hypotheses. Recent developments of MgH2 tanks are also presented.

Hydriding and Dehydriding Characteristics of As-Spun Nanocrystalline and Amorphous Mg20Ni10-xMnx (x = 0-4) Alloys

2011 ◽  
Vol 347-353 ◽  
pp. 3420-3424
Author(s):  
Yang Huan Zhang ◽  
Xiao Gang Liu ◽  
Le Le Chen ◽  
Hui Ping Ren ◽  
Guo Fang Zhang ◽  
...  
Keyword(s):  
Amorphous Phase ◽  
Hydrogen Absorption ◽  
Melt Spinning ◽  
Hydrogen Desorption ◽  
Absorption Capacity ◽  
Desorption Kinetics ◽  
Nanocrystalline And Amorphous ◽  
Cast Alloys ◽  
Mn Content ◽  
Kinetics Of

The nanocrystalline and amorphous Mg2Ni-type Mg20Ni10-xMnx (x = 0, 1, 2, 3, 4) alloys were synthesized by melt-spinning technique. The structures of the as-cast and spun alloys were characterized by XRD, SEM and HRTEM. The hydrogen absorption and desorption kinetics of the alloys were measured. The results show that the substitution of Mn for Ni, instead of changing the major phase Mg2Ni, leads to the formation of Mg and MnNi phases. No amorphous phase is detected in the as-spun Mn-free alloy, but the as-spun alloys substituted by Mn display the presence of an amorphous phase, suggesting that the substitution of Mn for Ni enhances the glass forming ability of the Mg2Ni-type alloy. The hydrogen absorption capacity of the as-cast alloys first increases and then decreases with the variation of the amount of Mn substitution. The hydrogen desorption capacity of the alloys markedly increases with growing Mn content.

Hydrogen absorption of C14 Laves NiTiZr-NiVNb pseudo-binary alloys

2003 ◽  
Vol 801 ◽  
Author(s):  
Kazuhiro Ishikawa ◽  
Shintaro Noda ◽  
Kiyonori Suzuki ◽  
Kiyoshi Aoki
Keyword(s):  
Binary System ◽  
Hydrogen Absorption ◽  
Binary Alloys ◽  
Hydrogen Desorption ◽  
Absorption Capacity ◽  
The Other ◽  
Hydrogen Capacity ◽  
Desorption Temperature ◽  
Other Hand ◽  
Zr Alloy

ABSTRACTHydrogen absorption and desorption properties of C14 Laves NiTiZr-NiVNb and NiTiZr-NiVZr pseudo-binary alloys were investigated by using the Sieverts' apparatus, XRD and the hydrogen analyzer. The hydrogen capacity and the 50% hydrogen desorption temperature, Td, of the C14 Laves NiTiZr alloy is 1.5 (H/M) and 850 K, respectively. On the other hand, the hydrogen capacity of the C14 NiVNb alloy is 0.2 H/M. In the Ni(TiZr)1−x(VNb)x pseudo-binary system, the hydrogen capacity of the alloys is decreased with increasing x, but the 50% hydrogen desorption temperature is almost constant. The substitution of VNb reduces the hydrogen absorption capacity of the C14 Laves NiTiZr alloy. The hydrogen desorption temperature of Ni(Ti1−xVx)Zr alloy is reduced to 580 K without serious decrease of the hydrogen capacity with increasing x.

Electrical resistivity and hydrogen-physisorption behavior of potassium-graphite intercalation compounds in the course of reactions with ammonia, water, and oxygen

1990 ◽  
Vol 5 (12) ◽  
pp. 2849-2853 ◽  
Author(s):  
N. Akuzawa ◽  
Y. Amari ◽  
T. Nakajima ◽  
Y. Takahashi
Keyword(s):  
Heat Treatment ◽  
Electrical Resistivity ◽  
Hydrogen Absorption ◽  
Absorption Capacity ◽  
Hydrogen Gas ◽  
Intercalation Compounds ◽  
Ammonia Content ◽  
Graphite Intercalation Compounds ◽  
Graphite Intercalation ◽  
Before And After

The electrical resistivity of potassium-graphite intercalation compounds (K–GICs) was measured in the course of reactions with ammonia, oxygen, water, etc, The hydrogen absorption behavior at 77 K was also investigated on K–GICs before and after the reactions. The electrical resistivity of KC8 increased by reactions with ammonia, furan, and water vapor, whereas almost no change was observed in the case of the reaction with oxygen. Molecules of ammonia, furan, and water are considered to penetrate into the KC8 interlayers, while oxygen draws potassium from interlayer spaces toward the surface with resultant potassium-diluted mixed stage compounds. The hydrogen absorption isotherms of K(NH3)xC31 (0 ≤ x ≤ 2.65) at 77 K showed that the saturated amount of absorbed hydrogen, (H2/K)sat, decreased linearly with increasing ammonia content, x, When x went up to 2, (H2/K)sat became zero. Similar behavior in the degradation of the hydrogen absorption capacity of K(H2O)xC25 (0 ≤ x ≤ 1.3) was observed. Contrary to such behavior, partially oxidized KC24 could not absorb hydrogen gas. These facts are also explained by taking into account the fact that ammonia and water molecules penetrate K–GICs, while oxygen draws potassium atoms toward the surface, as predicted from the electrical resistivity measurements. Successive oxidation and heat-treatment processes made KC8 more able to absorb hydrogen, while similar processes of ammoniation and hydration followed by heat-treatment did not.

Effects of CO2temperature on carbon aerogels porous structures and hydrogen absorption capacity

2011 ◽  
Vol 23 (7) ◽  
pp. 1853-1856
Author(s):  
袁秋月 Yuan Qiuyue ◽  
王朝阳 Wang Chaoyang ◽  
付志兵 Fu Zhibing ◽  
唐永建 Tang Yongjian ◽  
涂海燕 Tu Haiyan
Keyword(s):  
Hydrogen Absorption ◽  
Absorption Capacity ◽  
Carbon Aerogels ◽  
Porous Structures

Hydriding Properties of MgH2-Mg2Ni0.8Co0.2 Composites Obtained by Ball Milling

2007 ◽  
Vol 62 (7) ◽  
pp. 915-921 ◽  
Author(s):  
Tsveta Mandzhukova ◽  
Jean-Louis Bobet ◽  
Maria Khrussanova ◽  
Pavel Peshev
Keyword(s):  
Mechanical Activation ◽  
Ball Milling ◽  
Hydrogen Absorption ◽  
Catalytic Effect ◽  
Magnesium Hydride ◽  
Absorption Capacity ◽  
Favorable Effect ◽  
Inert Medium ◽  
Kinetics Of ◽  
Hydriding Kinetics

Abstract The hydrogen absorption-desorption characteristics of composites consisting of 90 wt.% MgH2- 10 wt.% Mg2Ni0.8Co0.2 prepared by ball milling for 30 and 180 min under argon have been investigated. The results obtained have been compared with those for the 90 wt.% Mg-10 wt.% Mg2Ni0.8Co0.2 composite synthesized in the same medium after 30 min of milling. The presence of the Mg2Ni0.8Co0.2 phase has been found to improve the hydriding kinetics of magnesium, the absorption capacity remaining high at temperatures below 573 K. The use of magnesium hydride instead of magnesium has proved to have a favorable effect on the properties of the composites after prolonged activation in an inert medium. It has been established that the absorption-desorption characteristics of the composite 90 wt.% MgH2-10 wt.% Mg2Ni0.8Co0.2 activated mechanically for 180 min are comparable with those of the composite 90 wt.% Mg-10 wt.% Mg2Ni0.8Co0.2 after mechanical activation for only 30 min. The favorable absorption-desorption characteristics of the composites have been explained with the catalytic effect of the additive, the presence of magnesium hydride and the duration of ball milling.

Doping with Metal and Compound to Improve the Properties of Hydrogen Storage of MgH2

2014 ◽  
Vol 1015 ◽  
pp. 606-609
Author(s):  
Yan Wang ◽  
Shi Wei Wu ◽  
Tian Le Li ◽  
Shen Shen Li ◽  
Zhong Qiu Cao
Keyword(s):  
High Temperature ◽  
Hydrogen Storage ◽  
Transition Metal Oxides ◽  
Hydrogen Absorption ◽  
Magnesium Hydride ◽  
Hydrogen Storage Materials ◽  
High Hydrogen ◽  
Practical Applications ◽  
Hydrogen Capacity ◽  
Advantages And Disadvantages

Recently, Magnesium hydride MgH2is one of the attractive hydrogen storage materials because it reaches a high hydrogen capacity. However, the reaction kinetics is too slow and needs high temperature for progressing hydrogen absorption and desorption reactions, which hinders the process of practical applications and it is necessary to improve the hydrogen storage propesties. In this paper, most used or under research methods (Doping with metal and compound) of improving on the hydrogen storage of magnesium hydride are reviewed, in particular to elements substitution, addition of transition metal oxides or fluorine and so on. The advantages and disadvantages of vaious methods of improving on the hydrogen storage of magnesium hydride are compared. The trend of the methods of improving is also introduced.

Synthesis of Titanate Nanotube from Different Phases of TiO2 Powders and Its Hydrogen Absorption Capacity

2009 ◽  
Vol 9 (2) ◽  
pp. 941-945 ◽  
Author(s):  
Dong Hyun Kim ◽  
Yi Hun Jung ◽  
Duck-Kyun Choi ◽  
Sun-Jae Kim ◽  
Kyung Sub Lee
Keyword(s):  
Hydrogen Absorption ◽  
Absorption Capacity ◽  
Titanate Nanotube
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