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• The FeCo@C and FeCoS@C catalysts are derived from ZIF-67. • A heterogeneous C supported Mg 2 Co, α-Fe, Co 3 Fe 7 and MgS catalyst system is formed. • The MgH 2 -FeCoS@C composite can absorb 4.56 wt% hydrogen within 900 s at 473 K. • The initial dehydrogenation temperature of MgH 2 -FeCoS@C composite is 550 K. • The dehydrogenation activation energy of MgH 2 is reduced to 91.9 kJ mol−1. The introduction of the heterogeneous catalysts with high activity can significantly improve hydrogen storage performance of MgH 2 , therefore, in this paper, we synthesize a carbon-supported transition metal compound, FeCoS@C derivative from ZIF-67, by utilizing the in situ formed C dispersive multiphase Mg 2 Co, α-Fe, Co 3 Fe 7 , and MgS to implement catalysis to MgH 2. Noteworthily, MgH 2 -FeCoS@C rapidly absorbs 6.78 wt% H 2 within 60 s at 573 K and can also absorb 4.56 wt% H 2 in 900 s at 473 K. Besides, the addition of FeCoS@C results in decreasing of the initial dehydrogenation temperatures of MgH 2 from 620 to 550 K. The dehydrogenation activation energy of MgH 2 decreases from 160.7 to 91.9 kJ mol–1. Studies show that the Mg 2 Co, α-Fe, and Co 3 Fe 7 act as "hydrogen channels" to accelerate hydrogen transfer due to the presence of transition metals, and MgS with excellent catalytic effect formed from MgH 2 -FeCoS@C provides a strong and stable catalytic effect. Besides, the carbon skeleton obtained by the carbonization of ZIF-67 not only serves as a dispersion for the multiphase catalytic system, but also provides more active sites for the catalysts. Our study shows that the multiphase and multiscale catalytic system provides an effective strategy for improving the hydrogen storage performance of MgH 2. [Display omitted] [ABSTRACT FROM AUTHOR]

The article offers information on the sustainable use of hydrogen as clean renewable energy source. Topics discussed include use of hydrogen as clean, safe and efficient fuel; problem with hydrogen such as storage; and use of hydrogen and oxygen by fuel cell to produce electricity. It also mention about scholarly papers and intellectual property protections by the American Army team.

Although already scientists in recent years have reported some experimental and theoretical results of La-Ni-Al series of tritium-storage alloys, several key aspects remain the subject of considerable debate. In an effort to interpret some of these unknowns, we have performed experimental and theoretical investigations for LaNi 5- x Al x ( x  = 0, 0.25, 0.5, 0.75 and 1.0) tritium-storage alloys. Firstly, the XRD characterization indicates that the unit cell volumes of LaNi 5- x Al x increase with Al content in alloys. Secondly, the PC-isotherm measurement of LaNi 5- x Al x alloys shows that their hydrogen absorption/desorption plateau pressures reduce with the increase of Al content while their plateau widths narrow simultaneously. The deuterium absorption/desorption plateaus have a similar trend to hydrogen’s except for their plateaus being higher than hydrogen’s. To explain the above experimental findings, a series of calculations based on density functional theory (DFT) and frozen phonon approach have been performed. The results manifest that: (1) the partial substitutions of Al for Ni reduce the hydrogen formation energies of LaNi 5- x Al x H and the number of available interstitial sites, and therefore lead to the absorption/desorption plateau pressures being reduced and the plateau widths being narrowed down at the same experimental temperatures; (2) the covalent interaction between H and Ni is an important factor for estimating the stability of LaNi 5- x Al x -H system; (3) since the calculated enthalpy change ΔH is generally more accurate than the calculated entropy change ΔS with respect to the corresponding experimental value for each LaNi 5- x Al x -H (or D), the curves of ΔH vs. hydrogen storage capacity instead of Van’t Hoff relation, can be used to predict the experimental plateau pressures of LaNi 5- x Al x -H (D or T) at a given temperature; (4) the hydrogen isotope effect of LaNi 5- x Al x -H (D or T) system can be quantitatively described as a linearity relation between Δ ZPE +  ΔH vib and 1 / m Q ( Q  = H, D, T). From the good agreement between the predicted and experimental ln ( P H / P 0 ) and ln ( P D / P 0 ) , it is deduced that predicting ln ( P T / P 0 ) of LaNi 5- x Al x T is feasible. The procedure of pre-computing and comparing curves of ΔH vs. hydrogen storage capacity proposed in this paper provided an attractive tool to increase the efficiency of experimental alloying design of hydrogen (deuterium or tritium) storage materials. [ABSTRACT FROM AUTHOR]

The article discusses seven revolutionary green technologies. Topics include the development of a memory material made of type of glass, called fused quartz, by physicist Peter Kazansky and colleagues that has more storage density than a fused quartz method developed by Japanese technology company Hitachi, the development of biodegradable plastics derived from the organic polymer chitin, called shrillk, by Donald Ingber and Javier Fernandez, and the development of the hydrogen storage material beryllium nanofoams by Fedor Naumkin and colleagues.

The article discusses National Aeronautics and Space Administration (NASA), a U.S. space agency efforts to develop a "zero boiloff" storage system for liquid hydrogen in space, using active cooling technology and a two-stage cooling approach. Topics discussed include the challenges of storing liquid hydrogen in space for extended durations, the use of cryocoolers to maintain "zero boiloff" conditions, and the development of a two-stage cooling approach to optimize mass and power savings.

The article presents several news briefs related to cryogenics as of April 1, 2018. Topics discussed include particle detector design proposed at Lawrence Berkeley National Laboratory could broaden the search for dark matter; information on study which determines use of Graphene as superconductors and insulators; and information on Hydrogen storage offered by white Graphene.

An excerpt from the article "Molecule discovery brings hydrogen storage a step closer," which appeared online on the website http://www.ecosmagazine.com/?paper=EC14181 is presented which focuses on the 28copper15hydride molecule which is significant to understand the use of hydrogen as fuel source.

The article focuses on the benefits of geologic storing of hydrogen, and talks of advantage for transportation fuel and grid-scale energy, fuel cell electric vehicles, and comment from Anna Snider Lord of Sandia National Laboratories of the U.S. Department of Energy.