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Id stringlengths 4 4	Abstract stringlengths 23 5.63k	Summary stringlengths 23 882	Unnamed: 3 stringclasses 1 value
!301	In the field of the solid state hydrogen-storage materials, boron-ammine compounds appears excellent dehydrogenation properties. But the key problems are centering on the circulation of hydrogenation and controllable dehydrogenation. However, maybe it's a huge improvement if we introduce the Frustrated Lewis Pairs (FLPs) such as Carbon-Phosphorous bonds into the hydrogen-storage compounds. Presently, we design 7 compounds containing FLPs structures and 14 pathways of (de)hydrogenation based on the experiments and compare their properties of hydrogenation kinetically and thermodynamically. The results suggest the hydrogenation is direct related to the difference between the two relevant atomic charges. It's easy to be hydrogenation between the atoms with small change of the atomic charges after the additive reaction. © 2016 Hydrogen Energy Publications LLC	However, maybe it's a huge improvement if we introduce the Frustrated Lewis Pairs (FLPs) such as Carbon-Phosphorous bonds into the hydrogen-storage compounds. Presently, we design 7 compounds containing FLPs structures and 14 pathways of (de)hydrogenation based on the experiments and compare their properties of hydrogenation kinetically and thermodynamically.	_
!302	The implementation of a future economy based on hydrogen-related energy needs an urgent development of efficient, safe, and economic solid-state hydrogen-storage materials. During the search process for novel materials for storing hydrogen, research interests in the past few decades have been intensively focused on light metal borohydrides and amides as two representative chemical complex hydrides with high hydrogen capacities. Recently, a large number of studies have reported new borohydride/amide combined systems that expand the scope of hydrogen-storage materials. Here, we review the interaction between light metal borohydrides and amides for storing hydrogen, with a special emphasis on the synthetic strategies and structural, physical, and chemical properties, which reveal a correlation between the composition, structure, and dehydrogenation properties and also provide general principles to the design of new combined systems with tailored functionality. This review also demonstrates the current progress on the dehydrogenation kinetic improvement of borohydride/amide combined systems. © 2017 The Royal Society of Chemistry.	The implementation of a future economy based on hydrogen-related energy needs an urgent development of efficient, safe, and economic solid-state hydrogen-storage materials. During the search process for novel materials for storing hydrogen, research interests in the past few decades have been intensively focused on light metal borohydrides and amides as two representative chemical complex hydrides with high hydrogen capacities.	_
!303	Hydride nanocomposites in the (LiNH2 + nMgH2) system have been synthesized by ball milling with varying input of milling energy injected into powder particles, QTR (kJ/g). The grain (crystallite) size of LiNH2 and MgH2 decreases rapidly with increasing QTR up to approximately 150-200 kJ/g and subsequently more or less saturates at the value of 10-20 nm. For the injected energy QTR ≈ 250-350 kJ/g the specific surface area (SSA) increases from the initial 2.4 m2/g for powder mixtures before milling to 30-37 m2/g for nanocomposites after milling. After injecting QTR ≈ 550 kJ/g there is a further increase of SSA to 52 m2/g which is over 20-fold increase of SSA from its initial value. That clearly indicates that a profound reduction of particle size has occurred. The hydride phases formed during ball milling with relatively low QTR are identified as a-Mg(NH 2)2 (amorphous magnesium imide) and LiH. The ball milled (LiNH2 + nMgH2) nanocomposite system with n = 0.5-0.9 can effectively desorb about 4-5 wt.% H2 with a reasonable rate at the temperature range close to 200 °C. Within a low temperature range up to ∼250 °C, regardless of the molar ratio n and the injected energy Q TR the thermal desorption of the (LiNH2 + nMgH 2) nanocomposites occurs without any release of ammonia, NH 3. For all molar ratios, n, the hydride nanocomposites are fully reversible at 175 °C under a relatively mild pressure of 50 bar H 2. The quantity of H2 desorbed decreases with increasing molar ratio n, due to increasing fraction of inactive, retained MgH2. However, at 125 °C the dehydrogenation rate is very sluggish and the quantity of released H2 is minimal. At the temperature range lower than ∼250 °C dehydrogenation of ball milled nanocomposites occurs through formation of the Li2Mg(NH)2 hydride phase. The value of the measured dehydrogenation enthalpy change of 46.7 kJ/molH 2 is relatively low and apparently, it is not responsible for sluggish dehydrogenation at 125 °C. The measurements of thermal conductivity for non-milled powders and ball milled nanocomposites show a dramatic reduction of thermal conductivity after ball milling. It seems that this could be a principal factor responsible for such a low dehydrogenation rate at low temperatures. © 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.	The hydride phases formed during ball milling with relatively low QTR are identified as a-Mg(NH 2)2 (amorphous magnesium imide) and LiH. For all molar ratios, n, the hydride nanocomposites are fully reversible at 175 °C under a relatively mild pressure of 50 bar H 2.	_
!304	Owing to a theoretical hydrogen storage capacity of 10.5 wt% H2, Ca(BH4)2+MgH2, the so-called calcium reactive hydride composite (Ca-RHC), has a great potential as a hydrogen storage material. However, its dehydrogenation temperature (∼623 K) is too high for any mobile applications. By addition of 10 mol% of NbF5 into Ca(BH4)2+MgH2, a decrease of the dehydrogenation onset temperature by ∼120 K is observed. In order to understand the reasons behind this desorption temperature decrement two sets of samples [Ca(BH4)2+MgH2 and Ca(BH4)2+MgH2+0.1NbF5] in different hydrogenation states, were prepared. The structural investigation of the above mentioned sets of samples by means of volumetric measurements, anomalous small-angle X-ray scattering (ASAXS) and X-ray absorption spectroscopy (XAS) is reported here. The XAS results show that after the milling procedure NbB2 is formed and remains stable upon further de/rehydrogenation cycling. The results of Nb ASAXS point to nanometric spherical NbB2 particles distributed in the hydride matrix, with a mean diameter of ∼10 nm. Results from Ca ASAXS indicate Ca-containing nanostructures in the Ca-RHC+0.1NbF5 samples to be ∼50% finer compared to those without additive. Thus, a higher reaction surface area and shorter diffusion paths for the constituents are concluded to be important contributions to the catalytic effect of an NbF5 additive on the hydrogen sorption kinetics of the Ca(BH4)2+MgH2 composite system. © 2014 International Union of Crystallography.	However, its dehydrogenation temperature (∼623 K) is too high for any mobile applications. In order to understand the reasons behind this desorption temperature decrement two sets of samples [Ca(BH4)2+MgH2 and Ca(BH4)2+MgH2+0.1NbF5] in different hydrogenation states, were prepared.	_
!305	Magnesium hydride is one of the most promising candidates for solid-state hydrogen storage and thermal energy storage applications. The effects of V-based solid solution alloys on the hydrogenation and dehydrogenation behavior of magnesium hydride are studied. Significant reduction of the dehydrogenation temperature and improvements of the kinetics of both absorption and desorption reactions were observed for MgH2with V-based additives. Those observations were made using thermogravimetric analysis (TGA) and pressure-composition-temperature (PCT) techniques. In situ synchrotron X-ray diffraction (XRD) measurements suggest that the additives functioned as catalysts during the reactions. The comparison of the characteristics of different additives suggested that the hydrogen equilibrium pressures of those additives themselves have a significant bearing on their effects on the kinetic behaviors of MgH2. The lower is the stability of an additive as a hydride, the more effective it would be as a catalyst. © 2014 American Chemical Society.	The effects of V-based solid solution alloys on the hydrogenation and dehydrogenation behavior of magnesium hydride are studied. Those observations were made using thermogravimetric analysis (TGA) and pressure-composition-temperature (PCT) techniques.	_
!306	The alkali metal silanides α-MSiH3 appear to be a promising family of complex hydrides for solid-state hydrogen storage. Herein the structural, energetic and electronic properties of α-MSiH3 silanides (M = Li, Na, K, Rb, Cs) and MSi Zintl phases are systematically investigated for the first time by using first-principles calculations method based on density functional theory. The structural parameters of α-MSiH3 and MSi including lattice constants and atomic positions are determined through geometry optimization. The obtained results are close to the experimental data analysed from X-ray and neutron powder diffraction. The calculations of formation enthalpy show that α-KSiH3, α-RbSiH3 and α-CsSiH3 silanides are easier to be synthetized relative to α-LiSiH3 and α-NaSiH3, which interprets well the lower thermostabilities of experimental α-LiSiH3 and α-NaSiH3. Nevertheless, LiSi, KSi and CsSi phases are easier to be formed relative to NaSi and RbSi. The calculations of hydrogen desorption enthalpy reveal that the dehydrogenation abilities of α-MSiH3 silanides along the decomposition path of α-MSiH3→MSi + H2 are gradually enhanced in the order of α-CsSiH3, α-RbSiH3, α-KSiH3, α-NaSiH3 and α-LiSiH3, which may be originated from their decreasing thermostabilities. From a comprehensive point of view including hydrogen storage capacity, thermostability and dehydrogenation ability, α-KSiH3 (∼4.29 wt%) is identified as the most promising alkali metal silanide for reversible hydrogen storage. Analysis of electronic structures indicates that a significant charge transfer leads to positively charged M ions and negatively charged SiH3 complex, which constitutes the ionic bonding between them. The bonding within SiH3 complex not only involves the covalent hybridization between Si (3s) (3p) and H (1s) orbitals, but also exhibits some ionic bond characteristics due to the partial charge transfer from Si to H. The covalent bonding interactions between H and Si atoms within SiH3 mainly dominate the thermostabilities and dehydrogenation properties of α-MSiH3 silanides. © 2017 Hydrogen Energy Publications LLC	The alkali metal silanides α-MSiH3 appear to be a promising family of complex hydrides for solid-state hydrogen storage. Herein the structural, energetic and electronic properties of α-MSiH3 silanides (M = Li, Na, K, Rb, Cs) and MSi Zintl phases are systematically investigated for the first time by using first-principles calculations method based on density functional theory.	_
!307	LiBH4 is considered as a prominent solid state hydrogen storage material with 18.3 wt% hydrogen storage capacity, while suffering sluggish dehydrogenation kinetics and poor reversibility. It is hypothesized that nano scale LiBH4 and catalyst mixture will show improved dehydrogenation performance. In this study, LiBH4 and Ni catalyst precursors were well mixed in organic solvent with activated carbon, followed by freeze drying and thermal reduction process. The as-prepared sample showed a nano Ni decorated LiBH4 clusters covered by the thin film of activated carbon, which helped reduce the doping amount of Ni catalyst and improve the reversibility of LiBH4. The onset of LiBH4 decomposition temperature was reduced to 243 °C with the first main hydrogen releasing peak at 278 °C. The sample desorbs 5.5 wt% hydrogen within 1 h at 330 °C. Although underwent serious degradation, a partial reversibility was observed under 9 MPa hydrogen pressure for 3 h at 400 °C. © 2014 Elsevier B.V. All rights reserved.	It is hypothesized that nano scale LiBH4 and catalyst mixture will show improved dehydrogenation performance. Although underwent serious degradation, a partial reversibility was observed under 9 MPa hydrogen pressure for 3 h at 400 °C.	_
!308	In this review, we discuss the evolution of localized surface plasmon resonance and surface plasmon resonance hydrogen sensors based on nanostructured metal hydrides, which has accelerated significantly during the past 5 years. We put particular focus on how, conceptually, plasmonic resonances can be used to study metal-hydrogen interactions at the nanoscale, both at the ensemble and at the single-nanoparticle level. Such efforts are motivated by a fundamental interest in understanding the role of nanosizing on metal hydride formation processes in the quest to develop efficient solid-state hydrogen storage materials with fast response times, reasonable thermodynamics, and acceptable long-term stability. Therefore, a brief introduction to the thermodynamics of metal hydride formation is also given. However, plasmonic hydrogen sensors not only are of academic interest as research tool in materials science but also are predicted to find more practical use as all-optical gas detectors in industrial and medical applications, as well as in a future hydrogen economy, where hydrogen is used as a carbon free energy carrier. Therefore, the wide range of different plasmonic hydrogen sensor designs already available is reviewed together with theoretical efforts to understand their fundamentals and optimize their performance in terms of sensitivity. In this context, we also highlight important challenges to be addressed in the future to take plasmonic hydrogen sensors from the laboratory to real applications in devices, including poisoning/deactivation of the active materials, sensor lifetime, and cross-sensitivity toward other gas species. © 2014 American Chemical Society.	Such efforts are motivated by a fundamental interest in understanding the role of nanosizing on metal hydride formation processes in the quest to develop efficient solid-state hydrogen storage materials with fast response times, reasonable thermodynamics, and acceptable long-term stability. Therefore, a brief introduction to the thermodynamics of metal hydride formation is also given.	_
!309	The phase transformations occurring as a function of the ball milling energy injected into the hydride system (LiNH2 + nMgH2), having molar ratios n = 0.5-2.0, have been thoroughly studied. The milling energy in a magneto-mill is estimated by a semi-empirical method. X-ray diffraction (XRD) and Fourier Transform Infrared (FT-IR) measurements show that for the molar ratios n < 1.0 three new phases such as LiH, amorphous Mg(NH2)2 (a-Mg(NH2)2) and Li 2Mg(NH)2 are formed during ball milling depending on the injected quantity of milling energy. Hydrogen is not released during milling when the LiH and a-Mg(NH2)2 hydrides are being formed whereas the formation of the Li2Mg(NH)2 hydride phase is always accompanied by a profound release of hydrogen. For the molar ratios n ≥ 1.0, at a low level of injected milling energy, the hydride phases formed are LiH and a-Mg(NH2)2. The latter reacts with MgH 2 during further milling to form the new phase MgNH whose formation is also accompanied by a profound release of hydrogen. Based on the experimental data we established an approximate hydride phase-injected milling energy diagram for various levels of injected milling energy and the molar ratios. © Copyright © 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.	X-ray diffraction (XRD) and Fourier Transform Infrared (FT-IR) measurements show that for the molar ratios n < 1.0 three new phases such as LiH, amorphous Mg(NH2)2 (a-Mg(NH2)2) and Li 2Mg(NH)2 are formed during ball milling depending on the injected quantity of milling energy. Based on the experimental data we established an approximate hydride phase-injected milling energy diagram for various levels of injected milling energy and the molar ratios.	_
!310	In Part A of this manuscript which consists of two parts, the experimental investigations pertaining to the absorption of hydrogen in an LmNi 4.91Sn0.15 based solid state hydrogen storage device with embedded cooling tubes (ECT) are presented. Two metal hydride based hydrogen storage devices with 36 and 60 ECT filled with 2.75 kg of LmNi 4.91Sn0.15 were fabricated. Performances of the hydrogen storage devices in terms of hydrogen absorption rate and amount of hydrogen absorbed are reported for different supply pressures (10-35 bar), absorption temperatures (20-30 C) and cooling fluid flow rates (2.2-30 l/min). At any given absorption temperature, the rate of hydrogen absorption and the amount of hydrogen absorbed are found to increase with hydrogen supply pressure up to about 35 bar. At the supply condition of 35 bar hydrogen pressure and 30 C absorption temperature, with oil as a heat transfer fluid at a flow rate of 3.2 l/min, the maximum amount of hydrogen absorbed are ≈1.18 wt% in 10 min for 36 ECT, and 8 min for 60 ECT. At the absorption condition of 25 bar supply pressure, 30 l/min water flow rate and 30 C absorption temperature, the absorption time of the reactor with 60 ECT was reduced to 5 min. © 2013, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserver.	In Part A of this manuscript which consists of two parts, the experimental investigations pertaining to the absorption of hydrogen in an LmNi 4.91Sn0.15 based solid state hydrogen storage device with embedded cooling tubes (ECT) are presented. At the supply condition of 35 bar hydrogen pressure and 30 C absorption temperature, with oil as a heat transfer fluid at a flow rate of 3.2 l/min, the maximum amount of hydrogen absorbed are ≈1.18 wt% in 10 min for 36 ECT, and 8 min for 60 ECT.	_
!311	Feasibility of using hydrochloric acid (HCl) as an accelerator for onboard production of hydrogen from sodium borohydride (NaBH4) is investigated. The aim was to examine process efficiency, hydrogen purity and process controllability which concurs onboard 2015 hydrogen storage target (5.5 wt%) for vehicular fuel cell system application. Results showed that a highest yield and controllable hydrogen production rate are achievable upon adopting onboard reaction of HCl (3 M) and an aqueous alkaline solution of 30 % NaBH4 via a T-junction and applying a gas–liquid separation of two stages. Cost evaluation and product stream analysis have demonstrated an exceptional performance for the examined scheme and relevancy to be adopted for feeding vehicular electrochemical fuel cell systems. © 2014, The Author(s).	The aim was to examine process efficiency, hydrogen purity and process controllability which concurs onboard 2015 hydrogen storage target (5.5 wt%) for vehicular fuel cell system application. Cost evaluation and product stream analysis have demonstrated an exceptional performance for the examined scheme and relevancy to be adopted for feeding vehicular electrochemical fuel cell systems.	_
!312	The use of transmission electron microscopy (TEM) for the structural characterization of many nanostructured hydrides, which are relevant for solid state hydrogen storage, is hindered due to a rapid decomposition of the specimen upon irradiation with the electron beam. Environmental TEM allows to stabilize the hydrides by applying a hydrogen back pressure of up to 4.5 bar in a windowed environmental cell. The feasibility of high-resolution TEM (HRTEM) investigations of light weight metals and metal hydrides in such a “nanoreactor” is studied theoretically by means of multislice HRTEM contrast simulations using Mg and its hydride phase, MgH2, as model system. Such a setup provides the general opportunity to study dehydrogenation and hydrogenation reactions at the nanoscale under technological application conditions. We analyze the dependence of both the spatial resolution and the HRTEM image contrast on parameters such as the defocus, the metal/hydride thickness, and the hydrogen pressure in order to explore the possibilities and limitations of in-situ experiments with windowed environmental cells. Such simulations may be highly valuable to pre-evaluate future experimental studies. © 2017 Elsevier B.V.	Environmental TEM allows to stabilize the hydrides by applying a hydrogen back pressure of up to 4.5 bar in a windowed environmental cell. Such simulations may be highly valuable to pre-evaluate future experimental studies.	_
!313	Since the current transportation sector is the largest consumer of oil, and subsequently responsible for major air pollutants, it is inevitable to use alternative renewable sources of energies for vehicular applications. The hydrogen energy seems to be a promising candidate. To explore the possibility of achieving a solid-state high-capacity storage of hydrogen for onboard applications, we have performed first-principles density functional theoretical calculations of hydrogen storage properties of beryllium oxide clusters (BeO)n (n = 2-8). We observed that a polar BeO bond is responsible for H2 adsorption. The problem of cohesion of beryllium atoms does not arise, as they are an integral part of BeO clusters. The (BeO)n (n = 2-8) adsorbs 8-12 H2 molecules with an adsorption energy in the desirable range of reversible hydrogen storage. The gravimetric density of H2 adsorbed on BeO clusters meets the ultimate 7.5 wt % limit, recommended for onboard practical applications. In conclusion, beryllium oxide clusters exhibit a remarkable solid-state hydrogen storage. © 2014 American Chemical Society.	Since the current transportation sector is the largest consumer of oil, and subsequently responsible for major air pollutants, it is inevitable to use alternative renewable sources of energies for vehicular applications. We observed that a polar BeO bond is responsible for H2 adsorption.	_
!314	Magnesium hydride is a very promising material for solid-state hydrogen storage. However, some drawbacks have to be overcome to use it in real applications. The use of catalysts is a viable solution to lower the desorption temperature and increase the overall kinetics. An accurate model has been developed to study the mechanism of action of the catalyst and how it interacts with the interface MgH2-Mg, through which H atoms diffuse. The accurate evaluation of the work of adhesion and defect energy formation, versus the distance from the interface are linked to the atomic-scale structural distortion induced by the catalyst. Moreover, molecular dynamics simulations at several temperature provide a clear description of the desorption mechanism and an estimate of the desorption temperature. © 2015 Hydrogen Energy Publications, LLC.	Magnesium hydride is a very promising material for solid-state hydrogen storage. Moreover, molecular dynamics simulations at several temperature provide a clear description of the desorption mechanism and an estimate of the desorption temperature.	_
!315	Solid-state hydrogen storage through the reversible formation of metallic hydrides is a key issue for the development of hydrogen as an energy vector. Herein we report the hydrogen storage performances of the KSiH3 phase ball-milled with NbF5 as a catalyst. The kinetics of hydrogen absorption/desorption are strongly enhanced by the addition of a catalyst as revealed by the large decrease of activation energies for both the absorption and desorption reactions. No disproportionation phenomenon is observed, indicating that the reaction between KSiH3 and KSi is perfectly reversible with a hydrogen storage capacity of 4.1 wt% H2. The thermodynamic properties of this KSi/KSiH3 equilibrium were investigated by plotting PCI curves from 90 °C to 130 °C: an enthalpy of 24.3 kJ mol-1 H2 and a low entropy change of 59.5 J K-1 mol-1 H2 are found. This low entropy variation is related to the high mobility of the H atoms in the α-KSiH3 phase as recently demonstrated by Quasi-Elastic Neutron Scattering (QENS) experiments. © The Royal Society of Chemistry.	Solid-state hydrogen storage through the reversible formation of metallic hydrides is a key issue for the development of hydrogen as an energy vector. No disproportionation phenomenon is observed, indicating that the reaction between KSiH3 and KSi is perfectly reversible with a hydrogen storage capacity of 4.1 wt% H2.	_
!316	Isosteric heat of hydrogen adsorption is one of the most important parameters required to describe solid-state hydrogen storage systems. Typically, it is calculated from adsorption isotherms measured at 77K (liquid N2) and 87K (liquid Ar). This simple calculation, however, results in a high degree of uncertainty due to the small temperature range. Therefore, the original Sievert type setup is upgraded using a heating and cooling device to regulate the wide sample temperature. This upgraded setup allows a wide temperature range for isotherms (77K~ 117K) providing a minimized uncertainty (error) of measurement for adsorption enthalpy calculation and yielding reliable results. To this end, we measure the isosteric heats of hydrogen adsorption of two prototypical samples: Activated carbon and metal-organic frameworks (e.g. MIL-53), and compared the small temperature range (77~87K) to the wide one (77K~ 117K). © Materials Research Society of Korea.	This simple calculation, however, results in a high degree of uncertainty due to the small temperature range. This upgraded setup allows a wide temperature range for isotherms (77K~ 117K) providing a minimized uncertainty (error) of measurement for adsorption enthalpy calculation and yielding reliable results.	_
!317	Complex hydrides have energy storage-related functions such as i) solid-state hydrogen storage, ii) electrochemical Li storage, and iii) fast Li- and Na-ionic conductions. Here, recent progress on the development of fast Li-ionic conductors based on the complex hydrides is reported. The validity of using them as electrolytes in all-solid-state lithium rechargeable batteries is also examined. Not only coated oxides but also bare sulfides are found to be applicable as positive electrode active materials. Results related to fast Na-ionic conductivity in the complex hydrides are presented. In the last section, the future prospects for battery assemblies with high-energy densities, and Mg ion batteries with the liquid and the solid-state electrolytes are discussed. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.	The validity of using them as electrolytes in all-solid-state lithium rechargeable batteries is also examined. Not only coated oxides but also bare sulfides are found to be applicable as positive electrode active materials.	_
!318	MgH2 is a promising material for reversible solid-state hydrogen storage. It is known that particle size can have a strong impact on hydrogen dynamics and sorption characteristics, but more detailed insight has been hampered by the great challenge to prepare small and well-defined particles and study their hydrogen storage properties upon cycling. The preparation of MgH2 nanoparticles supported on high surface area carbon aerogels with pore sizes varying from 6-20 nm is reported. Two distinctly different MgH2 particle populations are observed: X-ray diffraction invisible nanoparticles with sizes below 20 nm, and larger, crystalline, MgH2 particles. They release hydrogen at temperatures 140 °C lower than bulk MgH2. The size-dependent hydrogen kinetics is for the first time corroborated by intrinsic hydrogen dynamics data obtained by solid state 1H NMR. Fast cycling is possible (80% of the capacity absorbed within 15 min at 18 bar and 300 °C), without a change in the hydrogen sorption properties, showing that the growth of the nanoparticles is effectively prevented by the carbon support. A clear correlation is found between the hydrogen desorption temperature and the size of the MgH2 nanoparticles. This illustrates the potential of the use of supported nanoparticles for fast, reversible, and stable hydrogen cycling. Supported MgH2 nanoparticles on carbon with different sizes are synthesized and show faster hydrogen mobility and sorption kinetics. Nanoparticles with sizes below 20 nm have a significant lower hydrogen release temperature and the mobility is three orders of magnitude faster compared to micrometer sized MgH2. The smaller the MgH2 particles, the lower the hydrogen release temperatures become. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.	The preparation of MgH2 nanoparticles supported on high surface area carbon aerogels with pore sizes varying from 6-20 nm is reported. Nanoparticles with sizes below 20 nm have a significant lower hydrogen release temperature and the mobility is three orders of magnitude faster compared to micrometer sized MgH2.	_
!319	We present ab initio calculations to find the migration pathways of the hydrogen atom through Stone-Wales defects into the inside of the double-shell fullerene. We report that the most favorable pathway consists of the tunneling pathway through Stone-Wales defects on the double-shell C60/C 240 fullerene. This tunneling pathway gives rise to three barrier heights of 0.54eV, 0.47eV, and 0.7eV. The driving force for the hydrogen atom diffusion through the tunneling pathway towards the inside of the double-shell fullerene is 0.82eV. Our findings lead to a relatively low energy pathway, which provides a practical route to develop newly inexpensive solid-state hydrogen storages. © 2013 AIP Publishing LLC.	This tunneling pathway gives rise to three barrier heights of 0.54eV, 0.47eV, and 0.7eV. Our findings lead to a relatively low energy pathway, which provides a practical route to develop newly inexpensive solid-state hydrogen storages.	_
!320	Practical hydrogen storage for vehicular applications requires materials with high hydrogen densities, low decomposition temperature and fast adsorption and desorption kinetics. Till date, no reversible materials are currently known that posses all these attributes. Experimentally, testing the hydrogen storage capacity of a new material not only requires synthesis of a material but also the high precision equipments. The proposed material should also satisfy the target set by the US Department of Energy (DOE). If not, another material has to be synthesized. Theoretical H2 storage properties of a material can be evaluated precisely, and this may provide the mechanism to experimentalists for synthesizing such materials. Recent high performance computational techniques help us to predict the theoretical hydrogen uptake capacity of a material and provide information about its structure, stability and kinetics. Owing to their high uptake capacity at low temperature, structure stability, and excellent reversibility kinetics, organometallic nanostructures have attracted considerable attention as potential solid- state hydrogen storage materials. Here, the results from quantum chemical calculations on adsorption of dihydrogens on various organometallic complexes have been presented. Potential materials that were suited for storage of hydrogen in molecular form are particularly considered. The gravimetric H2 capacity of Scandium-decorated ethylene complex (14 wt%) is found to be well above the target specified by US DOE (5.5 wt% by 2015). Its cation adsorbs one additional molecule than the neutral thereby showing higher gravimetric H2 uptake by about 2 wt% than the neutral. Calculated averaged gain in energy of the complex favored for fast hydrogen adsorption and desorption kinetics. As found from many-body analysis technique, the H2 molecules interact strongly with the cation of C2H4:Sc than the neutral indicating an increase in metal bond strength. In case of Ti:C2H4 organometallic compound, it is found that the ionization process greatly improves its uptake capacity. The predicted gravimetric hydrogen uptake capacity of Ti:C2H4 (11.7 wt%) is in excellent agreement with the experimental value (12 wt%) reported earlier. Average Gibbs free energy correction was found to be as large as 0.45 eV and 0.44 eV for neutral and cation complexes, respectively. The Density Functional Theory (DFT) functionals as well as basis sets affect the averaged H2 adsorption energy with Gibbs free energy correction. The theoretical calculation of Equilibrium Isotope Effect (EIE) was also described. The vibrational frequencies of Ti:C2H4(nH2) and Ti:C2H4(nD2) for different 'n' are used to evaluate the EIE. The calculated EIE of 0.66 (for n=5) is also in excellent agreement with the experimental findings. Similar results were found in case of V:C2H4 complex. Hydrogen uptake capacity of V-capped and V-inserted V:C3H3 complexes was predicted and compared with other organometallic complexes containing single V atom decorated on different CnHn (n > 3) ring templates. The H2 uptake capacity of V:C3H3 organometallic compound is higher than other V-decorated CnHn (n > 3) ring templates reported earlier. The H2 adsorption on the V:C3H3 complex was found to be energetically favorable at finite temperature. The predicted hydrogen uptake capacity of the above systems was confirmed by the ab initio molecular dynamics simulations. © 2015 by Nova Science Publishers, Inc. All rights reserved.	Theoretical H2 storage properties of a material can be evaluated precisely, and this may provide the mechanism to experimentalists for synthesizing such materials. Owing to their high uptake capacity at low temperature, structure stability, and excellent reversibility kinetics, organometallic nanostructures have attracted considerable attention as potential solid- state hydrogen storage materials.	_
!321	2 LiNH2-1.1 MgH2-0.1 LiBH4-3 wt.% ZrCoH3 is a solid state hydrogen storage material with a hydrogen storage capacity of up to 5.3 wt.%. As the material shows sufficiently high desorption rates at temperatures below 200 °C, it is used for a prototype solid state hydrogen storage tank with a hydrogen capacity of 2 kWhel that is coupled to a high temperature proton exchange membrane fuel cell. In order to design an appropriate prototype reactor, model equations for the rate of hydrogen sorption reactions are required. Therefore in the present study, several material properties, like bulk density and thermodynamic data, are measured. Furthermore, isothermal absorption and desorption experiments are performed in a temperature and pressure range that is in the focus of the coupling system. Using experimental data, two-step model equations have been fitted for the hydrogen absorption and desorption reactions. These empirical model equations are able to capture the experimentally measured reaction rates and can be used for model validation of the design simulations. © 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.	In order to design an appropriate prototype reactor, model equations for the rate of hydrogen sorption reactions are required. Therefore in the present study, several material properties, like bulk density and thermodynamic data, are measured.	_
!322	Nanostructured materials based on light elements such as Li, Mg, and Na are essential for energy storage and conversion applications, but often difficult to prepare with control over size and structure. We report a new strategy that is illustrated for the formation of magnesium boron hydrides, relevant compounds for instance for reversible solid state hydrogen storage. We started with small (5-10 nm) MgH2 nanoparticles inside the ∼10 nm pores of a carbon scaffold, and larger MgH2 crystallites on the exterior surface of the scaffold. The large difference in reactivity between the two types of MgH2 is used to selective react the small MgH2 particles inside the pores with B2H6 to form magnesium boron hydrides under mild conditions. In this way pore-confined magnesium boron hydrides are formed with MgB12H12 as the major phase. Hydrogen release from the confined magnesium boron hydrides starts just above the synthesis temperature of 120 °C. The addition of Ni brings about the reaction to proceed readily at temperatures as low as 30 °C. Furthermore, by Ni addition and tuning the synthesis temperature, the product distribution can be steered toward Mg(BH4)2 and other magnesium boron hydrides. This shows the suitability of our method to selectively form pore-confined complex metal hydrides, such as MgB12H12 for which no synthesis strategy had been reported until now. This strategy might also be relevant for other novel energy storage and conversion materials, which are difficult to nanostructure in a controlled manner by conventional methods. © 2014 American Chemical Society.	This shows the suitability of our method to selectively form pore-confined complex metal hydrides, such as MgB12H12 for which no synthesis strategy had been reported until now. This strategy might also be relevant for other novel energy storage and conversion materials, which are difficult to nanostructure in a controlled manner by conventional methods.	_
!323	Hydrogen has been widely recognized as the "Energy Carrier" of the future. Efficient, reliable, economical and safe storage and delivery of hydrogen form important aspects in achieving success of the "Hydrogen Economy". Gravimetric and volumetric storage capacities become important when one considers portable and mobile applications of hydrogen. In the case of solid state hydrogen storage, the gas is reversibly embedded (by physisorption and/or chemisorption) in a solid matrix. A wide variety of materials such as intermetallics, physisorbents, complex hydrides/alanates, metal organic frameworks, etc. have been investigated as possible storage media. This paper discusses the feasibility of lithium- and sodium-aluminum hydrides with emphasis on their thermodynamic and thermo-physical properties. Drawbacks such as poor heat transfer characteristics and poor kinetics demand special attention to the thermal design of solid state storage devices. © 2014 Elsevier Ltd. All rights reserved.	A wide variety of materials such as intermetallics, physisorbents, complex hydrides/alanates, metal organic frameworks, etc. Drawbacks such as poor heat transfer characteristics and poor kinetics demand special attention to the thermal design of solid state storage devices.	_
!324	The combination of unstable hydrogen storage materials with a high pressure tank provides a potential solution to on-board hydrogen storage system for fuel cell vehicles. However, none of the available solid-state materials can fulfill all the requirements. In this work, Zr-Fe-V-based alloys were systematically investigated for the possible use in such kind of hybrid storage devices. Among these alloys studied here, the composition (Zr0.7Ti0.3)1.04Fe1.8V0.2 shows the best overall properties with a reversible hydrogen capacity of 1.51 wt%, and a hydrogen desorption pressure of 11.2 atm at 0 °C. Besides, this alloy also shows excellent stability without obvious capacity loss even after 200 hydrogen absorption/desorption cycles. Calculated results show that the gravimetric density of the hybrid storage system combining a 35 MPa high pressure tank with (Zr0.7Ti0.3)1.04Fe1.8V0.2 alloy is 1.95 wt% when the volumetric density reaches 40 kg/m3. © 2016 Hydrogen Energy Publications LLC.	Among these alloys studied here, the composition (Zr0.7Ti0.3)1.04Fe1.8V0.2 shows the best overall properties with a reversible hydrogen capacity of 1.51 wt%, and a hydrogen desorption pressure of 11.2 atm at 0 °C. Besides, this alloy also shows excellent stability without obvious capacity loss even after 200 hydrogen absorption/desorption cycles.	_
!325	Magnesium acetate was micronized by the supercritical antisolvent (SAS) process. By SAS processing, submicrometric magnesium acetate particles with particle sizes ranging from 300 to 700 nm with a regular spherical morphology and an amorphous crystalline structure were obtained. In comparison, mechanically milled particles showed similar mean particle sizes but had an irregular morphology and a bimodal particle size distribution. By calcination, SAS-processed magnesium acetate was converted into magnesium oxide, preserving the morphology of particles. By hydrogenation, the acetate was converted into magnesium hydride, a solid-state hydrogen storage metal hydride. The rate of release of hydrogen by thermolysis of magnesium hydride was enhanced by the particle size reduction, and there was a direct relationship between the size achieved by SAS micronization of the magnesium acetate precursor and the rate of release of hydrogen from the hydride. © 2014 American Chemical Society.	Magnesium acetate was micronized by the supercritical antisolvent (SAS) process. By SAS processing, submicrometric magnesium acetate particles with particle sizes ranging from 300 to 700 nm with a regular spherical morphology and an amorphous crystalline structure were obtained.	_
!326	Complex hydrides are a family of compounds which have attracted a lot of attention in the last decade for various clean energy-related purposes, from solid state hydrogen storage to materials suitable in Li-ion batteries. We present two new garnet-type borohydride materials suitable as solid state electrolytes. Li3K3Ce2(BH4)12 and Li3K3La2(BH4)12 show unexpectedly high room temperature Li+ ionic conductivity (compared to the reported isostructural garnet oxide Li-conductor) of σLi 3 × 10-7 and 6 × 10-7 S/cm with corresponding activation energies of Ea = 0.79 and Ea = 0.67 eV, respectively, which result from large bottleneck windows in the conduction path. The effect of heterovalent cation substitution is investigated as means of tailoring ionic conductivity. Doping with divalent Sr2+ and Eu2+ shows that σLi can be increased by one order of magnitude in the whole temperature range measured. © 2015 Elsevier B.V. All rights reserved.	Complex hydrides are a family of compounds which have attracted a lot of attention in the last decade for various clean energy-related purposes, from solid state hydrogen storage to materials suitable in Li-ion batteries. Doping with divalent Sr2+ and Eu2+ shows that σLi can be increased by one order of magnitude in the whole temperature range measured.	_
!327	One of the current main challenges in green-power storage and smart grids is the lack of effective solutions for accommodating the unbalance between renewable energy sources-offering intermittent electricity supply-and a variable electricity demand. Integrating intermittent renewable energy sources by safe and cost-effective energy storage systems is today achievable. Coupled with electrolizers, high-capacity solid-state storage of green-hydrogen is practicable to sustain integration, monitoring and control of large quantity of GWh from renewable generation. The 23.9 MLN Euros INGRID European large demonstrative project started in July 2012 combines magnesium-based material solid-state hydrogen storage systems with advanced ICT technologies to intelligently interconnect miscellaneous energy networks (i.e. electricity and gas) and safely delivering green-hydrogen to various existing or forthcoming markets. One solution INGRID project addresses is an off-grid utility to store renewable electricity captured from wind sources to refill full-battery electric cars. © 2016 by The Minerals. Metals & Materials Society.	The 23.9 MLN Euros INGRID European large demonstrative project started in July 2012 combines magnesium-based material solid-state hydrogen storage systems with advanced ICT technologies to intelligently interconnect miscellaneous energy networks (i.e. electricity and gas) and safely delivering green-hydrogen to various existing or forthcoming markets. One solution INGRID project addresses is an off-grid utility to store renewable electricity captured from wind sources to refill full-battery electric cars.	_
!328	Herein, we present the effect of the nanoconfinement of LiBH4 within porous aerogel-like carbon on its hydrogen storage properties. The carbon scaffold is prepared by salt templating - a facile and sustainable technique for the production of micro- and mesoporous carbon-based materials. A loading of up to 40 wt. % of LiBH4 is achieved by melt infiltration, and the hydride remains amorphous as shown by differential scanning calorimetry (DSC), X-ray diffractometry (XRD) and scanning transmission electron microscopy (STEM). Simultaneous thermogravimetry and mass spectroscopy (TG-MS) reveal that the nanoconfined LiBH4 starts to desorb hydrogen already at 200 °C with the main release at 310 °C. A partial rehydrogenation at moderate conditions (100 bar and 300 °C) is demonstrated. In contrast to recent reports, in-situ heating in the transmission electron microscope (STEM) and electron energy loss spectroscopy (EELS) indicate that both decomposition products (B and LiH) remain within the carbon pores. Nuclear magnetic resonance (NMR) measurements reveal the presence of amorphous and partially oxidized boron in the dehydrogenated sample that may impede the reversibility of the (de)hydrogenation process. © 2016 Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.	% of LiBH4 is achieved by melt infiltration, and the hydride remains amorphous as shown by differential scanning calorimetry (DSC), X-ray diffractometry (XRD) and scanning transmission electron microscopy (STEM). In contrast to recent reports, in-situ heating in the transmission electron microscope (STEM) and electron energy loss spectroscopy (EELS) indicate that both decomposition products (B and LiH) remain within the carbon pores.	_
!329	The main objective of the SSH2S (Fuel Cell Coupled Solid State Hydrogen Storage Tank) project was to develop a solid state hydrogen storage tank based on complex hydrides and to fully integrate it with a High Temperature Proton Exchange Membrane (HT-PEM) fuel cell stack. A mixed lithium amide/magnesium hydride system was used as the main storage material for the tank, due to its high gravimetric storage capacity and relatively low hydrogen desorption temperature. The mixed lithium amide/magnesium hydride system was coupled with a standard intermetallic compound to take advantage of its capability to release hydrogen at ambient temperature and to ensure a fast start-up of the system. The hydrogen storage tank was designed to feed a 1 kW HT-PEM stack for 2 h to be used for an Auxiliary Power Unit (APU). A full thermal integration was possible thanks to the high operation temperature of the fuel cell and to the relative low temperature (170 °C) for hydrogen release from the mixed lithium amide/magnesium hydride system. © 2017 Elsevier B.V.	The main objective of the SSH2S (Fuel Cell Coupled Solid State Hydrogen Storage Tank) project was to develop a solid state hydrogen storage tank based on complex hydrides and to fully integrate it with a High Temperature Proton Exchange Membrane (HT-PEM) fuel cell stack. A mixed lithium amide/magnesium hydride system was used as the main storage material for the tank, due to its high gravimetric storage capacity and relatively low hydrogen desorption temperature.	_
!330	Nanocrystalline MgH2 powders were prepared by reactive ball milling of pure Mg powders under 50 bar of a hydrogen gas atmosphere, using a high energy ball mill operated at room temperature. The end-product of MgH2 powders obtained after 200 h of a continuous ball milling time composed of γ and β phases. The end-product was doped with 7 wt% of Mn3.6Ti2.4 powders and then mechanically milled under a hydrogen gas atmosphere for 50 h, using a high energy ball mill for different ball milling time. This end product coexisted with Fe and Cr contamination contents of 2.16 and 0.74 wt%, respectively. The effect of the ball milling time on the morphological characterizations, thermal stability and hydrogenation/dehydrogenation properties of MgH2/7 wt% Mn3.6Ti2.4 powders were investigated. The powders obtained after 50 h of milling had spherical-like morphology and homogeneously with uniform composition close to the starting nominal composition. Moreover, this binary nanocomposite system possessed superior hydrogenation/dehydrogenation kinetics at 275 °C, as suggested by the short time required to absorb and desorb 5.3 wt% H2 within 2 and 8 min, respectively. At this temperature, the synthesized nanocomposite powders possessed excellent absorption/desorption cyclability of 1000 complete cycles within 1400 h. However, a minor degradation (∼0.3-0.4 wt% H2) in the hydrogen storage capacity was observed between 410 h and 1400 h of the cycle-life-time. This slight degradation took place due to the grain growth came off in the Mg/Mn3.6Ti2.4 grains. © 2015 Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.	Nanocrystalline MgH2 powders were prepared by reactive ball milling of pure Mg powders under 50 bar of a hydrogen gas atmosphere, using a high energy ball mill operated at room temperature. The end-product was doped with 7 wt% of Mn3.6Ti2.4 powders and then mechanically milled under a hydrogen gas atmosphere for 50 h, using a high energy ball mill for different ball milling time.	_
!331	Hydrogen diffusion impacts the performance of solid-state hydrogen storage materials and contributes to the embrittlement of structural materials under hydrogen-containing environments. In atomistic simulations, the diffusion energy barriers are usually calculated using molecular statics simulations where a nudged elastic band method is used to constrain a path connecting the two end points of an atomic jump. This approach requires prior knowledge of the "end points". For alloy and defective systems, the number of possible atomic jumps with respect to local atomic configurations is tremendous. Even when these jumps can be exhaustively studied, it is still unclear how they can be combined to give an overall diffusion behavior seen in experiments. Here we describe the use of molecular dynamics simulations to determine the overall diffusion energy barrier from the Arrhenius equation. This method does not require information about atomic jumps, and it has additional advantages, such as the ability to incorporate finite temperature effects and to determine the pre-exponential factor. As a test case for a generic method, we focus on hydrogen diffusion in bulk aluminum. We find that the challenge of this method is the statistical variation of the results. However, highly converged energy barriers can be achieved by an appropriate set of temperatures, output time intervals (for tracking hydrogen positions), and a long total simulation time. Our results help elucidate the inconsistencies of the experimental diffusion data published in the literature. The robust approach developed here may also open up future molecular dynamics simulations to rapidly study diffusion properties of complex material systems in multidimensional spaces involving composition and defects. © 2016 American Chemical Society.	In atomistic simulations, the diffusion energy barriers are usually calculated using molecular statics simulations where a nudged elastic band method is used to constrain a path connecting the two end points of an atomic jump. The robust approach developed here may also open up future molecular dynamics simulations to rapidly study diffusion properties of complex material systems in multidimensional spaces involving composition and defects.	_
!332	A computational platform is developed in the Modelica®language within the Dymola™ environment to provide a tool for the design and performance comparison of on-board hydrogen storage systems. The platform has been coupled with an open source library for hydrogen fueling stations to investigate the vehicular tank within the frame of a complete refueling system. The two technologies that are integrated in the platform are solid-state hydrogen storage in the form of metal hydrides and compressed gas systems. In this work the computational platform is used to compare the storage performance of two tank designs based on the tubular tank configuration with Ti1.1CrMn as the absorbing alloy. Results show that a shell and tube layout with metal hydride tubes of 2 mm inner diameter achieves the desired refueling time of 3 min and store a maximum of 3.1 kg of hydrogen in a 126 L tank, corresponding to a storage capacity four times larger than a tube-in-tube solution of the same size. The volumetric and gravimetric densities of the shell and tube are 2.46% and 1.25% respectively. The dehydriding ability of this solution is proven to withstand intense discharging conditions. © 2016 Hydrogen Energy Publications LLC	Results show that a shell and tube layout with metal hydride tubes of 2 mm inner diameter achieves the desired refueling time of 3 min and store a maximum of 3.1 kg of hydrogen in a 126 L tank, corresponding to a storage capacity four times larger than a tube-in-tube solution of the same size. The dehydriding ability of this solution is proven to withstand intense discharging conditions.	_
!333	Modern metallurgy has a close collaboration with many other industrial fields and also with gas production industry. Using of hydrogen and nitrogen atmospheres in steel production and rolling show us metallurgy industry in a role of a big consumer of industrial gases. But from other side, metallurgy plants and companies always plays the role of suppliers for gas industry. This type of collaboration is not new, but in last decade's a development of powder metallurgy provides new possibility for two industries connection on the way of creation new types of energy storage systems, based on metal hydrides. Using of intermetallic compounds for hydrogen storage in solid form with the formation of chemical compounds (metal hydrides) with the possibility of sorption and desorption, provides energy storage systems with hydrogen densities greater than in the liquid and gaseous states. Hydrogen storage in intermetallic systems can be the most energy efficient and less energy consuming way of hydrogen storing in the near future. In present article the description of real applications and conditions of intermetallic systems, and possibilities to use metal compounds for creation energy storage systems and using that systems in real life is provided.	But from other side, metallurgy plants and companies always plays the role of suppliers for gas industry. Using of intermetallic compounds for hydrogen storage in solid form with the formation of chemical compounds (metal hydrides) with the possibility of sorption and desorption, provides energy storage systems with hydrogen densities greater than in the liquid and gaseous states.	_
!334	The renewable resources related, for instance, to solar energies exhibit two main characteristics. They have no practical limits in regards to the efficiency and their various capture methods. However, their intermittence prevents any direct and immediate use of the resulting power. McPhy-Energy proposes solutions based on water electrolysis for hydrogen generation and storage on reversible metal hydrides to efficiently cover various energy generation ranges from MW h to GW h. Large stationary storage units, based on MgH2, are presently developed, including both the advanced materials and systems for a total energy storage from ∼70 to more than 90% efficient. Various designs of MgH2-based tanks are proposed, allowing the optional storage of the heat of the Mg-MgH2 reaction in an adjacent phase changing material. The combination of these operations leads to the storage of huge amounts of hydrogen and heat in our so-called adiabatic-tanks. Adapted to intermittent energy production and consumption from renewable sources (wind, sun, tide, etc.), nuclear over-production at night, or others, tanks distribute energy on demand for local applications (on-site domestic needs, refueling stations, etc.) via turbine or fuel cell electricity production. © 2013 Elsevier B.V. All rights reserved.	They have no practical limits in regards to the efficiency and their various capture methods. ), nuclear over-production at night, or others, tanks distribute energy on demand for local applications (on-site domestic needs, refueling stations, etc.)	_
!335	Metal borohydrides offer high theoretical storage capacity for solid state hydrogen storage. This work is aimed at the mechanochemical synthesis of Yb(BH4)3 from LiBH4 and YbCl3. Different synthesis routes resulted in three new compounds, LiYb(BH 4)4-xClx, α-Yb(BH4) 3 and β-Yb(BH4)3. Their crystal structures have been determined from lab and synchrotron powder diffraction. LiYb(BH 4)4-xClx takes a primitive tetragonal structure with x = 1.0, a = 6.1729(3) Å and c = 12.4155(10) Å in the space group P42c (no. 112), α-Yb(BH4)3 a primitive cubic structure with a = 10.70715(15) Å in the space group Pa3 (no. 205), and β-Yb(BH4)3 a primitive cubic structure with a = 5.44223(3) Å in the space group Pm3m (no. 221). Thermal decomposition properties of the materials have been investigated by in situ synchrotron radiation powder X-ray diffraction, thermo gravimetric analysis/differential scanning calorimetry and temperature programmed desorption. The decomposition product, Yb(BH4)2-xClx, adopting a primitive tetragonal structure with space group P4 (no. 81) was formed after release of diborane gas, and x increases with increasing temperature. A deuterated sample of this compound was synthesized for powder neutron diffraction. Rietveld refinement gave x = 0.76, a = 6.74763(2) Å and c = 4.28368(2) Å. Another polymorph of Yb(BH4)2-xClx was synthesized, which adopts a primitive orthorhombic structure with space group Pbca (no. 61), where x = 0.3, a = 13.20997(20) Å, b = 8.26829(12) Å and c = 7.44532(11) Å. © The Royal Society of Chemistry 2013.	Thermal decomposition properties of the materials have been investigated by in situ synchrotron radiation powder X-ray diffraction, thermo gravimetric analysis/differential scanning calorimetry and temperature programmed desorption. Another polymorph of Yb(BH4)2-xClx was synthesized, which adopts a primitive orthorhombic structure with space group Pbca (no.	_
!336	Hydrogen is conventionally stored as either a compressed gas or a cryogenic liquid. However, the lack of efficient storage materials has thus far critically limited the widespread adoption of hydrogen, and to overcome this limitation, a promising solid-state storage method is needed. Attractive lightweight metal-based materials for solid-state storage are characterized by the capability to reversibly store a large quantity of hydrogen and should meet or exceed the United States Department of Energy (DOE) on-board storage targets. However, the undesirable kinetic performances of metal hydrides as solid-state storage materials have hindered their practical use as hydrogen storage systems. The kinetic performances, which include the rate of hydrogen uptake or release, are among the most critical requirements of a storage system, and these performances can be determined using the hydrogen absorption and desorption rates. Thus, determining the relevant kinetics is required to supply sufficient amounts of hydrogen and to achieve fast refueling in the system. This review summarizes the kinetic performances and the efforts toward enhancing the hydrogen absorption/desorption kinetics of light metal-based materials. © 2016	However, the lack of efficient storage materials has thus far critically limited the widespread adoption of hydrogen, and to overcome this limitation, a promising solid-state storage method is needed. Attractive lightweight metal-based materials for solid-state storage are characterized by the capability to reversibly store a large quantity of hydrogen and should meet or exceed the United States Department of Energy (DOE) on-board storage targets.	_
!337	Energy is one of the basic requirements in our daily lives. Daily activities such as cooking, cleaning, working on the computer and commuting to work are more or less dependent on energy. The world's energy demand is continuously increasing over the years due to the ever-increasing growth in the human population as well as economic development. At present, approximately 90% of energy demands are fulfilled by fossil fuels. With the rising demands of energy throughout the globe, it can be expected that the availability of fossil fuels is depleting at an alarming rate since fossil fuels are non-renewable sources of energy. In addition, fossil fuels are the main contributor of greenhouse gas emissions and therefore, they have a detrimental impact on human health and environment in the long term. Hence, there is a critical need to develop alternative sources of energy in replacement of fossil fuels. Hydrogen fuels have gained much interest among researchers all over the world since they are clean, non-toxic and renewable, making them suitable for use as substitutes for petroleum-derived fuels in vehicular applications. However, the greatest challenge in using hydrogen fuels lies in the development of hydrogen storage systems, especially for on-board applications. Hydrogen fuels can be stored in gaseous, liquid or solid states, and much effort has been made to develop hydrogen storage systems that are safe, cost-effective, environmental-friendly and more importantly, with high energy densities. Current technologies used for hydrogen storage include high-pressure compression at about 70 MPa, liquefaction at cryogenic temperatures (20 K) and absorption into solid state compounds. Among the three types of hydrogen storage technologies, the storage of hydrogen in solid state compounds appears to be the most feasible solution since it is a safer and more convenient method compared to high-pressure compression and liquefaction technologies. In this regard, metal hydrides are potential chemical compounds for solid-state hydrogen storage, and a large number of studies have been carried out to synthesize low-cost metal hydrides with low absorption/desorption temperatures, high gravimetric and volumetric hydrogen storage densities, good resistance to oxidation, good reversibility and cyclic ability, fast kinetics and reactivity, and moderate thermodynamic stability. In general, these studies have shown that the absorption/desorption properties of hydrogen can be improved by: (1) the addition of catalysts into the metal hydrides, (2) alloying the metal hydrides, or (3) nanostructuring. This review article is focused on the latest developments of metal hydrides for solid-state hydrogen storage applications, which will be of interest to scientists, researchers, and practitioners in this field. © 2016 Hydrogen Energy Publications LLC	Hydrogen fuels have gained much interest among researchers all over the world since they are clean, non-toxic and renewable, making them suitable for use as substitutes for petroleum-derived fuels in vehicular applications. Hydrogen fuels can be stored in gaseous, liquid or solid states, and much effort has been made to develop hydrogen storage systems that are safe, cost-effective, environmental-friendly and more importantly, with high energy densities.	_
!338	Determining the thermal conductivity is crucial whenever heat transfer issues are considered which play a major role in many technological applications. However, various materials are sensitive to oxygen or moisture and, therefore, cannot be examined with commonly used equipment under ambient conditions. Here, we present a novel approach which combines the inert requirements of ambient-sensitive specimens with the flash method in which the apparatus, a Netzsch LFA 447 NanoFlash®, is placed under ambient conditions. A new measuring cell with flashtransparent windows was constructed which resembles a gas-tight specimen chamber. This device can be easily adapted to other apparatuses based on the flash method. The thermal conductivities of reference materials in inert and ambient conditions were examined in a temperature range from 25 to 275 °C. In general an excellent agreement was found. Further, the usability of this special sample cell is demonstrated for the investigation of the thermal conductivities of two complex hydride systems which are important for solid-state hydrogen storage applications. © Akadémiai Kiadó, Budapest, Hungary 2013.	Determining the thermal conductivity is crucial whenever heat transfer issues are considered which play a major role in many technological applications. However, various materials are sensitive to oxygen or moisture and, therefore, cannot be examined with commonly used equipment under ambient conditions.	_
!339	Zr(BH4)4·8NH3 is considered to be a promising solid-state hydrogen-storage material, due to its high hydrogen density and low dehydrogenation temperature. However, the release of ammonia hinders its practical applications. To further reduce the dehydrogenation temperature and suppress ammonia release, here we investigated its hydrolysis process to evaluate its hydrogen generation performance. The results showed that the hydrolysis of Zr(BH4)4·8NH3 in water can generate about 1067 mL g-1 pure hydrogen in 240 min at 298 K without the release of diborane or ammonia impurity gases. With heat-assistance, the hydrogen generation rate can be significantly enhanced, and its activation energy was calculated to be 29.38 kJ mol-1. The hydrolysis mechanism was clarified. The results demonstrate that Zr(BH4)4·8NH3 may work as one promising hydrogen generation material. © The Royal Society of Chemistry 2017.	To further reduce the dehydrogenation temperature and suppress ammonia release, here we investigated its hydrolysis process to evaluate its hydrogen generation performance. The results demonstrate that Zr(BH4)4·8NH3 may work as one promising hydrogen generation material.	_
!340	The state of the art of conversion reactions of metal hydrides (MH) with lithium is presented and discussed in this review with regard to the use of these hydrides as anode materials for lithium-ion batteries. A focus on the gravimetric and volumetric storage capacities for different examples from binary, ternary and complex hydrides is presented, with a comparison between thermodynamic prediction and experimental results. MgH2 constitutes one of the most attractive metal hydrides with a reversible capacity of 1480 mA·h·g-1 at a suitable potential (0.5 V vs Li+/Li0) and the lowest electrode polarization (<0.2 V) for conversion materials. Conversion process reaction mechanisms with lithium are subsequently detailed for MgH2, TiH2, complex hydrides Mg2MHx and other Mg-based hydrides. The reversible conversion reaction mechanism of MgH2, which is lithium-controlled, can be extended to others hydrides as: MHx + xLi+ + xe- in equilibrium with M + xLiH. Other reaction paths-involving solid solutions, metastable distorted phases, and phases with low hydrogen content-were recently reported for TiH2 and Mg2FeH6, Mg2CoH5 and Mg2NiH4. The importance of fundamental aspects to overcome technological difficulties is discussed with a focus on conversion reaction limitations in the case of MgH2. The influence of MgH2 particle size, mechanical grinding, hydrogen sorption cycles, grinding with carbon, reactive milling under hydrogen, and metal and catalyst addition to the MgH2/carbon composite on kinetics improvement and reversibility is presented. Drastic technological improvement in order to the enhance conversion process efficiencies is needed for practical applications. The main goals are minimizing the impact of electrode volume variation during lithium extraction and overcoming the poor electronic conductivity of LiH. To use polymer binders to improve the cycle life of the hydride-based electrode and to synthesize nanoscale composite hydride can be helpful to address these drawbacks. The development of high-capacity hydride anodes should be inspired by the emergent nano-research prospects which share the knowledge of both hydrogen-storage and lithium-anode communities. © 2015 Aymard et al.	The reversible conversion reaction mechanism of MgH2, which is lithium-controlled, can be extended to others hydrides as: MHx + xLi+ + xe- in equilibrium with M + xLiH. Drastic technological improvement in order to the enhance conversion process efficiencies is needed for practical applications.	_