Materials design and modification on amide-based composites for hydrogen storage

AbstractAmide-based composite system has the potential to meet the needs of onboard hydrogen storage for fuel cell vehicles due to its relatively high hydrogen capacity and tunable thermodynamics. A large number of amide–hydride and amide–complex hydride composites have been developed in the past decades. This article reviews the state-of-the-arts of amide–hydride composite systems with the focus on the materials design and modification

KNH2 - KH: a metal amide - hydride solid solution

We report for the first time the formation of a metal amide-hydride solid solution. The dissolution of KH into KNH2 leads to an anionic substitution, which decreases the interaction among NH2 - ions. The rotational properties of the high temperature polymorphs of KNH2 are thereby retained down to room temperature.Fil: Santoru, Antonio. Helmholtz-zentrum Geesthacht; Alemania. Università di Torino; ItaliaFil: Pistidda, Claudio. Helmholtz-zentrum Geesthacht; AlemaniaFil: Sørby, Magnus H.. Institute for Energy Technology. Physics Department; NoruegaFil: Chierotti, Michele R.. Università di Torino; ItaliaFil: Garroni, Sebastian. University of Sassari; ItaliaFil: Pinatel, Eugenio. Università di Torino; ItaliaFil: Karimi, Fahim. Helmholtz-zentrum Geesthacht; AlemaniaFil: Cao, Hujun. Helmholtz-zentrum Geesthacht; AlemaniaFil: Bergemann, Nils. Helmholtz-zentrum Geesthacht; AlemaniaFil: Le, Thi T.. Helmholtz-zentrum Geesthacht; AlemaniaFil: Puszkiel, Julián Atilio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; ArgentinaFil: Gobetto, Roberto. Università di Torino; ItaliaFil: Baricco, Marcello. Università di Torino; ItaliaFil: Hauback, Bjorn C.. Institute for Energy Technology. Physics Department; NoruegaFil: Klassen, Thomas. Helmholtz-zentrum Geesthacht; AlemaniaFil: Dornheim, Martín. Helmholtz-zentrum Geesthacht; Alemani

Enhancement effect of bimetallic amide K2Mn(NH2)4 and in-situ formed KH and Mn4N on the dehydrogenation/hydrogenation properties of Li–Mg–N–H system

In this work, we investigated the influence of the K2Mn(NH2)4 additive on the hydrogen sorption properties of the Mg(NH2)2 + 2LiH (Li–Mg–N–H) system. The addition of 5 mol% of K2Mn(NH2)4 to the Li–Mg–N–H system leads to a decrease of the dehydrogenation peak temperature from 200 ◦C to 172 ◦C compared to the pristine sample. This sample exhibits a constant hydrogen storage capacity of 4.2 wt.% over 25 dehydrogenation/rehydrogenation cycles. Besides that, the in-situ synchrotron powder X-ray diffraction analysis performed on the as prepared Mg(NH2)2 + 2LiH containing K2Mn(NH2)4 indicates the presence of Mn4N. However, no crystalline K-containing phases were detected. Upon dehydrogenation, the formation of KH is observed. The presence of KH and Mn4N positively influences the hydrogen sorption properties of this system, especially at the later stage of rehydrogenation. Under the applied conditions, hydrogenation of the last 1 wt.% takes place in only 2 min. This feature is preserved in the following three cycles.Fil: Gizer, Gökhan. Helmholtz zentrum Geesthacht; AlemaniaFil: Cao, Hujun. Helmholtz zentrum Geesthacht; Alemania. Chinese Academy of Sciences; República de ChinaFil: Puszkiel, Julián Atilio. Helmholtz zentrum Geesthacht; Alemania. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; ArgentinaFil: Pistidda, Claudio. Helmholtz zentrum Geesthacht; AlemaniaFil: Santoru, Antonio. Helmholtz zentrum Geesthacht; AlemaniaFil: Zhang, Weijin. Chinese Academy of Sciences; República de ChinaFil: He, Teng. Chinese Academy of Sciences; República de ChinaFil: Chen, Ping. Chinese Academy of Sciences; República de ChinaFil: Klassen, Thomas. Helmholtz zentrum Geesthacht; Alemania. Helmut Schmidt Universität; ArgentinaFil: Dornheim, Martin. Helmholtz zentrum Geesthacht; Alemani

Recent progress and new perspectives on metal amide and imide systems for solid-state hydrogen storage

Hydrogen storage in the solid state represents one of the most attractive and challenging ways to supply hydrogen to a proton exchange membrane (PEM) fuel cell. Although in the last 15 years a large variety of material systems have been identified as possible candidates for storing hydrogen, further efforts have to be made in the development of systems which meet the strict targets of the Fuel Cells and Hydrogen Joint Undertaking (FCH JU) and U.S. Department of Energy (DOE). Recent projections indicate that a system possessing: (i) an ideal enthalpy in the range of 20–50 kJ/mol H2, to use the heat produced by PEM fuel cell for providing the energy necessary for desorption; (ii) a gravimetric hydrogen density of 5 wt. % H2 and (iii) fast sorption kinetics below 110 °C is strongly recommended. Among the known hydrogen storage materials, amide and imide-based mixtures represent the most promising class of compounds for on-board applications; however, some barriers still have to be overcome before considering this class of material mature for real applications. In this review, the most relevant progresses made in the recent years as well as the kinetic and thermodynamic properties, experimentally measured for the most promising systems, are reported and properly discussedEuropean Marie Curie Actions under ECOSTORE grant agreement No. 60704

Medeuro : the longing for identity and community among Maltese migrant settlers in North Africa

Based largely on materials held in the Service des Periodiques at the Bibliotheque Nationale de Tunisie in Tunis, and especially on content anaylsis of a 1930s newspaper Melita published in Sousse. this study explores the yearning for and the anguish of a cultural survivance among Maltese migrant settlers in North Africa, above all the retention of Maltese as a language of expression, affinity and identification, at a time when Maltese itself was experiencing a literary rebirth. However, such a campaign is undertaken in a 'non-Maltese' context, where moreover, in addition to separation and distance, the influence of European empires-the French, the British and the Italian-is pronounced, if not dominant, thus interfering with any continued loyalty to one mother tongue or mother country. Masterminding the intellectual push for a collective self-identity anchored in language, literature, history and religion, is a leading francophone litterateur whose family had settled in Algeria from the island of Gozo. What is also offered here, in the annotations, is a fairly comprehensive bibliography of Maltese migrant settlement in northern Africa with special reference to lesser known articles and other publications not available in English.peer-reviewe

Electron attachment to the DNA bases adenine and guanine and dehydrogenation of their anionic derivatives: Density functional study

Density functional theory (DFT) calculations have been used to explore electron attachment to the purines adenine and guanine and their hydrogen atom loss. Calculations show that the dehydrogenation at the N9 site in the adenine and guan: ne transient anions is the lowest-cost channel of hydrogen loss, and the N9-H bond scission has Gibbs free energies of dissociation Delta H degrees of 8.8 kcal mol(-1) for the anionic adenine and 13.9 kcal mol(-1) for the anionic guanine. The relatively high feasibility of low-energy electron (LEE)-induced N9-H bond cleavage in the purine nucleobases arises from high electron affinities of their H-deleted counterparts. Unlike adenine, other N-H bond dissociations are competitive with the N9-H bond fission in the anionic guanine. The replacement of hydrogen in the ring of purine has a significant effect on the N9-H bond fragmentation. (c) 2006 Wiley Periodicals, Inc