Note: Times Cited: 875 Reference EPFL-ARTICLE-206025doi:10.1021/cr0501846View record in Web of Science URL: ://WOS:000249839900009 Record created on 2015-03-03, modified on 2017-05-12

/pdf/complex-hydrides-for-hydrogen-storage-vphufvreyb.pdf

Complex hydrides for hydrogen storage.

Widespread adoption of hydrogen as a vehicular fuel depends critically upon the ability to store hydrogen on-board at high volumetric and gravimetric densities, as well as on the ability to extract/insert it at sufficiently rapid rates As current storage methods based on physical means—high-pressure gas or (cryogenic) liquefaction—are unlikely to satisfy targets for performance and cost, a global research effort focusing on the development of chemical means for storing hydrogen in condensed phases has recently emerged At present, no known material exhibits a combination of properties that would enable high-volume automotive applications Thus new materials with improved performance, or new approaches to the synthesis and/or processing of existing materials, are highly desirable In this critical review we provide a practical introduction to the field of hydrogen storage materials research, with an emphasis on (i) the properties necessary for a viable storage material, (ii) the computational and experimental techniques commonly employed in determining these attributes, and (iii) the classes of materials being pursued as candidate storage compounds Starting from the general requirements of a fuel cell vehicle, we summarize how these requirements translate into desired characteristics for the hydrogen storage material Key amongst these are: (a) high gravimetric and volumetric hydrogen density, (b) thermodynamics that allow for reversible hydrogen uptake/release under near-ambient conditions, and (c) fast reaction kinetics To further illustrate these attributes, the four major classes of candidate storage materials—conventional metal hydrides, chemical hydrides, complex hydrides, and sorbent systems—are introduced and their respective performance and prospects for improvement in each of these areas is discussed Finally, we review the most valuable experimental and computational techniques for determining these attributes, highlighting how an approach that couples computational modeling with experiments can significantly accelerate the discovery of novel storage materials (155 references)

http://www-personal.umich.edu/~djsiege/Energy_Storage_Lab/Publications_files/CSR_H2_storage.pdf

High capacity hydrogen storage materials: attributes for automotive applications and techniques for materials discovery

Materials for hydrogen storage: current research trends and perspectives

Since the beginning of the twenty-first century the limitations of the fossil age with regard to the continuing growth of energy demand, the peaking mining rate of oil, the growing impact of CO2 emissions on the environment and the dependency of the economy in the industrialized world on the availability of fossil fuels became very obvious. A major change in the energy economy from fossil energy carriers to renewable energy fluxes is necessary. The main challenge is to efficiently convert renewable energy into electricity and the storage of electricity or the production of a synthetic fuel. Hydrogen is produced from water by electricity through an electrolyser. The storage of hydrogen in its molecular or atomic form is a materials challenge. Some hydrides are known to exhibit a hydrogen density comparable to oil; however, these hydrides require a sophisticated storage system. The system energy density is significantly smaller than the energy density of fossil fuels. An interesting alternative to the direct storage of hydrogen are synthetic hydrocarbons produced from hydrogen and CO2 extracted from the atmosphere. They are CO2 neutral and stored like fossil fuels. Conventional combustion engines and turbines can be used in order to convert the stored energy into work and heat.

https://www.jstor.org/stable/pdfplus/25699171.pdf

Hydrogen: the future energy carrier

Note: Times Cited: 251 Reference EPFL-ARTICLE-206012doi:10.1103/PhysRevB.74.045126View record in Web of Science URL: ://WOS:000239426800043 Record created on 2015-03-03, modified on 2017-05-12

/pdf/correlation-between-thermodynamical-stabilities-of-metal-2xymq561j1.pdf

Correlation between thermodynamical stabilities of metal borohydrides and cation electronegativites: First-principles calculations and experiments

Dehydriding reactions of mixed complex hydrides

Combination of LiBH4 and LiNH2 by ball milling forms the series of novel complex hydrides Li2BNH6, Li3BN2H8 and Li4BN3H10, depending on the combination ratios The crystal structure of Li4BN3H10 analyzed by synchrotron X-raydiffraction measurements is determined to be a cubic system (space group: I213) with the lattice constant of a=10673(2)A It should be emphasized that Li4BN3H10 is an ionic crystal which is composed of a lithium cation Li+ and two different kinds of the complex anion [BH4]- and [NH2]- These anions are located in the vertex and face-center of the cubic sub-lattice, and the lithium cation Li+ in the interstitial site between the anions, respectively The other series of complex hydrides, Li2BNH6 and Li3BN2H8, are also predicted to possess similar structures composed of a lithium cation Li+ and two different kinds of the complex anion [BH4]- and [NH2]-

Crystal structure analysis of novel complex hydrides formed by the combination of LiBH4 and LiNH2

An effective method for developing amide-based high-performance hydrogen storage materials is to prepare appropriate combinations of amides and hydrides. We have proposed that a mixture of an amide with a low decomposition temperature and a hydride showing rapid reaction to ammonia would be an appropriate combination. According to this proposal, the mixture of Mg(NH2)2 (Mg amide) and LiH (Li hydride) was investigated. The dehydriding temperature of the mixture of Mg(NH2)2 and 4� LiH is lower than that of the mixture of LiNH2 (Li amide) and 2� LiH. A method for preventing ammonia release is increasing the LiH ratio in the mixtures, which results in a reduction in the amount of desorbed hydrogen. The homogeneous dispersion between Mg(NH2)2 and LiH might be also an important factor for preventing ammonia release.

/pdf/guidelines-for-developing-amide-based-hydrogen-storage-41r0jqmwjz.pdf

Guidelines for developing amide-based hydrogen storage materials

A carbonitrided member obtained from a base steel material which contains 0.10-0.35% carbon, 0.15-1.0% silicon, 0.30-1.0% manganese, 0.40-2.0% chromium, and up to 0.05% sulfur and optionally further contains up to 0.50% molybdenum, with the remainder being iron and impurities. The carbonitrided member contains iron nitride particles of e-Fe3N and/or zeta-Fe2N dispersed in the region of from the surface of the case to an effective case depth, and residual austenite has been decomposed into bainitic ferrite, Fe3C, and a''-Fe16N2. Although the carbonitrided member has a reduced content of molybdenum, which is expensive, or contains no molybdenum, the member can have excellent wearing resistance and high pitting strength. This carbonitrided member can be produced, for example, by subjecting the base steel material to carburization in which the base material is held in a 900-950 C carburizing atmosphere and successively to carbonitriding in which the material is held in a carbonitriding atmosphere having a temperature of 800-900 C and a nitrogen potential of 0.2-0.6%, subsequently quenching the material, and thereafter tempering the material by heating to a temperature in the range of from 250 C to 350 C, excluding 250 C.

Akihito Ninomiya

Papers

Correlation between thermodynamical stabilities of metal borohydrides and cation electronegativites: First-principles calculations and experiments

Dehydriding reactions of mixed complex hydrides

Crystal structure analysis of novel complex hydrides formed by the combination of LiBH4 and LiNH2

Guidelines for developing amide-based hydrogen storage materials

Carbonitrided member and process for producing carbonitrided member