The Experts below are selected from a list of 243 Experts worldwide ranked by ideXlab platform
Peihong Zhang - One of the best experts on this subject based on the ideXlab platform.
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Charging-assisted hydrogen release mechanism in layered Boron Hydride
Physical Review B, 2011Co-Authors: Tesfaye A. Abtew, Peihong ZhangAbstract:We present a first-principles study of the dehydrogenation mechanism of a recently proposed layered Boron Hydride (B${}_{2}$H${}_{2}$) for hydrogen storage. The nudged elastic band method is employed to study the kinetic energy barrier against the release of hydrogen. Introducing additional charges into the B${}_{2}$H${}_{2}$ system reduces the electron deficiency of Boron layer thereby lowering the dehydrogenation kinetic energy barrier. Finite-temperature molecular dynamics simulation further confirms the release of hydrogen atoms and the formation of molecular hydrogen upon charging the system. The Boron network remains intact throughout the simulation up to at least 500 K. These results suggest a charging-assisted dehydrogenation mechanism in this system.
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Prediction of a multicenter-bonded solid Boron Hydride for hydrogen storage
Physical Review B, 2011Co-Authors: Tesfaye A. Abtew, Bi-ching Shih, Pratibha Dev, Vincent H. Crespi, Peihong ZhangAbstract:An ideal material for on-board hydrogen storage must release hydrogen at practical temperature and pressure and also regenerate efficiently under similarly gentle conditions. Therefore, thermodynamically, the Hydride material must lie within a narrow range near the hydrogenation/dehydrogenation phase boundary. Materials involving only conventional bonding mechanisms are unlikely to meet these requirements. In contrast, materials containing certain frustrated bonding are designed to be on the verge of frustration-induced phase transition, and they may be better suited for hydrogen storage. Here we propose a novel layered solid Boron Hydride and show its potential for hydrogen storage. The absence of soft phonon modes confirms the dynamical stability of the structure. Charging the structure significantly softens hydrogen-related phonon modes. Boron-related phonons, in contrast, are either hardened or not significantly affected by electron doping. These results suggest that electrochemical charging may facilitate hydrogen release while the underlying Boron network remains intact for subsequent rehydrogenation.
Paul V. R. Schleyer - One of the best experts on this subject based on the ideXlab platform.
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solid state and solution structures of 9 vertex arachno Boron Hydride clusters an ab initio iglo nmr study
Inorganic Chemistry, 1999Co-Authors: And Matthias Hofmann, Paul V. R. SchleyerAbstract:The ab initio/IGLO/NMR method clarifies the structures of several 9-vertex Boron Hydride clusters by comparing computed chemical shifts using various geometries with NMR data in solution. The exper...
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Solid State and Solution Structures of 9-Vertex Arachno Boron Hydride Clusters. An ab Initio/IGLO/NMR Study
Inorganic Chemistry, 1999Co-Authors: And Matthias Hofmann, Paul V. R. SchleyerAbstract:The ab initio/IGLO/NMR method clarifies the structures of several 9-vertex Boron Hydride clusters by comparing computed chemical shifts using various geometries with NMR data in solution. The exper...
Nurettin Sahiner - One of the best experts on this subject based on the ideXlab platform.
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Hydrogel assisted nickel nanoparticle synthesis and their use in hydrogen production from sodium Boron Hydride
International Journal of Hydrogen Energy, 2011Co-Authors: Ozgur Ozay, Nahit Aktas, Erk Inger, Nurettin SahinerAbstract:Abstract In this study, hydrogels were synthesized from 2-acrylamido-2-methyl-1-propansulfonic acid (AMPS) via a photo polymerization technique. Approximately 100 nm Ni metal nanoparticles were generated in situ inside these p(AMPS) hydrogel networks and used as a catalyst in hydrogen production by hydrolysis of sodium Boron Hydride in a basic medium. The effects of several parameters on the hydrolysis reaction such as the amount of catalyst, the initial concentration of NaBH 4 , and the temperature were investigated. The activation energy, activation enthalpy and activation of entropy for the reaction were calculated as 42.28 kJ mol −1 , 39.59 kJ mol −1 and −171.67 J mol −1 K −1 , respectively.
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Superabsorbent hydrogels for cobalt nanoparticle synthesis and hydrogen production from hydrolysis of sodium Boron Hydride
Applied Catalysis B-environmental, 2010Co-Authors: Nurettin Sahiner, Ozgur Ozay, Erk Inger, Nahit AktasAbstract:Abstract Polymeric hydrogels derived from 2-acrylamido-2-methyl-1-propansulfonic acid (AMPS) were utilized in the preparation of cobalt (Co) metal nanoparticles and used as a composite–catalyst system in hydrogen generation from the hydrolysis of NaBH 4 . The embedded Co nanoparticles in the p(AMPS) networks are on the order of 100 nm. It was demonstrated that the p(AMPS)–Co composite system was very effective in the production of hydrogen from alkali aqueous sodium Boron Hydride solutions. The effect of various parameters such as the initial concentration of NaBH 4 , the amount of catalyst and temperature on the hydrolysis reaction was evaluated. The activation energy for hydrogen production by Co particles was found to be 38.14 kJ mol −1 ; while the activation enthalpy was 35.46 kJ mol −1 .
Nahit Aktas - One of the best experts on this subject based on the ideXlab platform.
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Hydrogel assisted nickel nanoparticle synthesis and their use in hydrogen production from sodium Boron Hydride
International Journal of Hydrogen Energy, 2011Co-Authors: Ozgur Ozay, Nahit Aktas, Erk Inger, Nurettin SahinerAbstract:Abstract In this study, hydrogels were synthesized from 2-acrylamido-2-methyl-1-propansulfonic acid (AMPS) via a photo polymerization technique. Approximately 100 nm Ni metal nanoparticles were generated in situ inside these p(AMPS) hydrogel networks and used as a catalyst in hydrogen production by hydrolysis of sodium Boron Hydride in a basic medium. The effects of several parameters on the hydrolysis reaction such as the amount of catalyst, the initial concentration of NaBH 4 , and the temperature were investigated. The activation energy, activation enthalpy and activation of entropy for the reaction were calculated as 42.28 kJ mol −1 , 39.59 kJ mol −1 and −171.67 J mol −1 K −1 , respectively.
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Superabsorbent hydrogels for cobalt nanoparticle synthesis and hydrogen production from hydrolysis of sodium Boron Hydride
Applied Catalysis B-environmental, 2010Co-Authors: Nurettin Sahiner, Ozgur Ozay, Erk Inger, Nahit AktasAbstract:Abstract Polymeric hydrogels derived from 2-acrylamido-2-methyl-1-propansulfonic acid (AMPS) were utilized in the preparation of cobalt (Co) metal nanoparticles and used as a composite–catalyst system in hydrogen generation from the hydrolysis of NaBH 4 . The embedded Co nanoparticles in the p(AMPS) networks are on the order of 100 nm. It was demonstrated that the p(AMPS)–Co composite system was very effective in the production of hydrogen from alkali aqueous sodium Boron Hydride solutions. The effect of various parameters such as the initial concentration of NaBH 4 , the amount of catalyst and temperature on the hydrolysis reaction was evaluated. The activation energy for hydrogen production by Co particles was found to be 38.14 kJ mol −1 ; while the activation enthalpy was 35.46 kJ mol −1 .
Tesfaye A. Abtew - One of the best experts on this subject based on the ideXlab platform.
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Charging-assisted hydrogen release mechanism in layered Boron Hydride
Physical Review B, 2011Co-Authors: Tesfaye A. Abtew, Peihong ZhangAbstract:We present a first-principles study of the dehydrogenation mechanism of a recently proposed layered Boron Hydride (B${}_{2}$H${}_{2}$) for hydrogen storage. The nudged elastic band method is employed to study the kinetic energy barrier against the release of hydrogen. Introducing additional charges into the B${}_{2}$H${}_{2}$ system reduces the electron deficiency of Boron layer thereby lowering the dehydrogenation kinetic energy barrier. Finite-temperature molecular dynamics simulation further confirms the release of hydrogen atoms and the formation of molecular hydrogen upon charging the system. The Boron network remains intact throughout the simulation up to at least 500 K. These results suggest a charging-assisted dehydrogenation mechanism in this system.
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Prediction of a multicenter-bonded solid Boron Hydride for hydrogen storage
Physical Review B, 2011Co-Authors: Tesfaye A. Abtew, Bi-ching Shih, Pratibha Dev, Vincent H. Crespi, Peihong ZhangAbstract:An ideal material for on-board hydrogen storage must release hydrogen at practical temperature and pressure and also regenerate efficiently under similarly gentle conditions. Therefore, thermodynamically, the Hydride material must lie within a narrow range near the hydrogenation/dehydrogenation phase boundary. Materials involving only conventional bonding mechanisms are unlikely to meet these requirements. In contrast, materials containing certain frustrated bonding are designed to be on the verge of frustration-induced phase transition, and they may be better suited for hydrogen storage. Here we propose a novel layered solid Boron Hydride and show its potential for hydrogen storage. The absence of soft phonon modes confirms the dynamical stability of the structure. Charging the structure significantly softens hydrogen-related phonon modes. Boron-related phonons, in contrast, are either hardened or not significantly affected by electron doping. These results suggest that electrochemical charging may facilitate hydrogen release while the underlying Boron network remains intact for subsequent rehydrogenation.