Li-decorated carbyne for hydrogen storage: charge induced polarization and van't Hoff hydrogen desorption temperature

2020 ◽  
Vol 4 (2) ◽  
pp. 691-699 ◽  
Author(s):  
Ekaterina Anikina ◽  
Amitava Banerjee ◽  
Valery Beskachko ◽  
Rajeev Ahuja

Low dimensions for hydrogen storage media: exceeding U.S. DOE uptake target on Li-functionalized carbyne with hydrogen binding energies needed for good cyclability.

2005 ◽  
Vol 475-479 ◽  
pp. 2431-2436
Author(s):  
Yuko Nakamori ◽  
G. Kitahara ◽  
T. Kudo ◽  
T. Yamagishi ◽  
Shinichi Orimo

Fundamental researches on complex hydrides are recently of great importance to develop practical hydrogen storage materials with higher gravimetric hydrogen densities than those of conventional materials. First, in this paper, we clarify the correlation between B-H atomistic vibrations in [BH4]--anion and melting temperatures of MBH4 (M = Li, Na, and K) as indexes of hydrogen desorption temperatures. This investigation implies that partial cation substitutions using smaller sized- and/or higher valenced-cations with higher electronegativities might provide higher energy modes of Raman spectra, and then, lower hydrogen desorption temperatures. Next, as an example, LiNH2 and its partial cation substitution materials are examined. At the start of the reaction, the hydrogen desorption temperature for LiNH2 with partial cation substitution drastically decreased, with the increase in Mg concentration, to around 370K for the sample with x = 30.


2016 ◽  
Vol 16 (1) ◽  
pp. 18-20
Author(s):  
Maulinda Maulinda ◽  
Zulkarnain Jalil ◽  
Adi Rahwanto

One of the future technologies for a safe hydrogen storage media is  metal hydrides. Currently, Mg-based metal hydride has a safety factor and efficient for vehicle applications. However, the thermodynamic properties of magnesium hydride (MgH2) found a relatively high temperature. High desorption temperatures caused MgH2 high thermodynamic stability resulting desorption enthalpy is also high. In this study, natural mineral (iron ore) has been extracted from iron sand into powder of magnetite (Fe3O4) and used as a catalyst in an effort to improve the desorption properties of MgH2. Magnetie has been successfully extracted from iron sand using precipitation method with a purity of 85 % , where the purity of the iron sand before extracted was 81%. Then, MgH2-Fe3O4 was milling using mechanical alloying method with a variety of catalysts and milling time. The observation by XRD showed the material was reduced to nanocrystalline scale. MgH2 phase appears as the main phase. DSC test results showed with the addition of Fe3O4, the desorption temperature can be reduced up to 366oC, compared to pure pure MgH2 reached by 409o C. Furthermore, based on gravimetric test, the hydrogen release occurs at a temperature of 388o C, weight loss  of 0.66 mg during 16 minutes.


Molecules ◽  
2021 ◽  
Vol 26 (6) ◽  
pp. 1722
Author(s):  
Troy Semelsberger ◽  
Jason Graetz ◽  
Andrew Sutton ◽  
Ewa C. E. Rönnebro

We present the research findings of the DOE-funded Hydrogen Storage Engineering Center of Excellence (HSECoE) related to liquid-phase and slurry-phase chemical hydrogen storage media and their potential as future hydrogen storage media for automotive applications. Chemical hydrogen storage media other than neat liquid compositions will prove difficult to meet the DOE system level targets. Solid- and slurry-phase chemical hydrogen storage media requiring off-board regeneration are impractical and highly unlikely to be implemented for automotive applications because of the formidable task of developing solid- or slurry-phase transport systems that are commercially reliable and economical throughout the entire life cycle of the fuel. Additionally, the regeneration cost and efficiency of chemical hydrogen storage media is currently the single most prohibitive barrier to implementing chemical hydrogen storage media. Ideally, neat liquid-phase chemical hydrogen storage media with net-usable gravimetric hydrogen capacities of greater than 7.8 wt% are projected to meet the 2017 DOE system level gravimetric and volumetric targets. The research presented herein is a collection of research findings that do not in and of themselves warrant a dedicated manuscript. However, the collection of results do, in fact, highlight the engineering challenges and short-comings in scaling up and demonstrating fluid-phase ammonia borane and alane compositions that all future materials researchers working in hydrogen storage should be aware of.


2012 ◽  
Vol 586 ◽  
pp. 50-57
Author(s):  
Yang Huan Zhang ◽  
Tai Yang ◽  
Hong Wei Shang ◽  
Guo Fang Zhang ◽  
Xia Li ◽  
...  

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.


RSC Advances ◽  
2015 ◽  
Vol 5 (75) ◽  
pp. 60983-60989 ◽  
Author(s):  
N. Juahir ◽  
N. S. Mustafa ◽  
A. M. Sinin ◽  
M. Ismail

The result showed that the addition of 10 wt% Co2NiO to the MgH2 exhibits a lower onset desorption temperature. The dehydrogenation and rehydrogenation kinetics of MgH2 + 10 wt% Co2NiO were also improved compared to un-doped MgH2.


2004 ◽  
Vol 837 ◽  
Author(s):  
M. W. Zandbergen ◽  
S. W. H. Eijt ◽  
W. J. Legerstee ◽  
H. Schut ◽  
V. L. Svetchnikov

ABSTRACTThe hydrogen storage properties of nanostructured Mg and MgH2 thin films were studied as created by Ar and Ar+H2 plasma sputter deposition. Columnar structures with typical widths of ∼120 nm are observed with their long columnar axis extending throughout the thickness of the films. Applying substrate bias voltages during deposition results in narrower columns. A concomitant reduction in hydrogen desorption temperature from 400 °C to 360 °C is observed. Capping the Mg films with a ∼100 nm thin Pd layer leads to significantly reduced hydrogen desorption temperatures of ∼200 °C induced by the catalytic activity of the Pd cap layer. Also, hydrogen permeation of the films is strongly improved. The rate-determining factor is found to be the dissociation of the hydrogen molecules. Optimum hydrogen loading conditions of the Pd/Mg films were obtained just above ∼200 °C at hydrogen pressures of 0.25–1.0 MPa, resulting in hydrogen storage capacities in the range of 4–7 wt%.


2019 ◽  
Vol 3 (4) ◽  
pp. 956-964 ◽  
Author(s):  
Jun Sugiyama ◽  
Izumi Umegaki ◽  
Mitsuru Matsumoto ◽  
Kazutoshi Miwa ◽  
Hiroshi Nozaki ◽  
...  

To study the mechanism determining the desorption temperature of hydrogen storage materials, we have measured muon spin rotation and relaxation (μ+SR) in MgH2 together with the pressure in the sample space.


2019 ◽  
Vol 804 ◽  
pp. 35-40
Author(s):  
Ning Ning Zhou ◽  
Dong Ying Ju

This study proposed the new method of preparing Mg-based composite by mixed powder Ni and Ti onto the surface of pure Mg ingot. The prepared method caused that hydrogen absorbing phase Mg2Ni and catalytic phase NiTi generated and distributed regularly. The pure Mg ingot as the center and the powder Ni and Ti as cladding material on the surface were formed and sintered, in which the temperature range of generated alloy phase Mg2Ni and NiTi was confirmed at first; according to the temperature range, the size of Mg2Ni and NiTi crystal grains at 650°C and 850°C were analyzed and compared, respectively; The size of Mg2Ni alloy phase at the surface and center was calculated by comparing the atomic radius of Ni, Ti to confirm that Mg2Ni distributed on the surface due to the atom Ti replaced the atom Ni in Mg2Ni to generate the alloy phase NiTi; the capacity of the hydrogen desorption reached 4wt% within 5min. The disadvantages that easy to chalking and difficult to activate in the conventional method were avoided and achieved the application of the multilayer composite material in hydrogen storage field.


Sign in / Sign up

Export Citation Format

Share Document