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Environmentally friendly nanocrystalline magnesium hydride decorated with metallic glassy-zirconium palladium nanopowders for fuel cell applications

A new solid-state hydrogen storage system of magnesium hydride (MgH(2)) doped with 5 wt% of metallic glassy (MG) zirconium palladium (Zr(2)Pd) nanopowder was fabricated using a high-energy ball milling technique. The end-product obtained after 50 h of milling was consolidated into bulk buttons, usin...

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Autores principales: El-Eskandarany, M. Sherif, Banyan, Mohammad, Al-Ajmi, Fahad
Formato: Online Artículo Texto
Lenguaje:English
Publicado: The Royal Society of Chemistry 2019
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9070806/
https://www.ncbi.nlm.nih.gov/pubmed/35530499
http://dx.doi.org/10.1039/c9ra05121j
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author El-Eskandarany, M. Sherif
Banyan, Mohammad
Al-Ajmi, Fahad
author_facet El-Eskandarany, M. Sherif
Banyan, Mohammad
Al-Ajmi, Fahad
author_sort El-Eskandarany, M. Sherif
collection PubMed
description A new solid-state hydrogen storage system of magnesium hydride (MgH(2)) doped with 5 wt% of metallic glassy (MG) zirconium palladium (Zr(2)Pd) nanopowder was fabricated using a high-energy ball milling technique. The end-product obtained after 50 h of milling was consolidated into bulk buttons, using a hot-pressing technique at 350 °C. The results have shown that this consolidation step, followed by the repetitive pressing at ambient temperature did not affect the nanocrystalline characteristics of pressed powders. Recycling pressing demonstrated beneficial effects of plastic deformation and lattice imperfections on Mg, leading to its enhanced hydrogenation/dehydrogenation kinetics and cycle-life-time performance compared with untreated samples. The results elucidated that spherical, hard, nanopowder of MG-Zr(2)Pd were forced to penetrate the Mg/MgH(2) matrix to create micro/nanopore structures upon pressing for 50 cycles. These ultrafine spherical metallic glassy particles (∼400 nm in diameter) acted as a micro-milling media for reducing the particle size of MgH(2) powders into submicron particles. In addition, they played a vital role as grain growth inhibitors to prevent the undesired growth of Mg grains upon the application of a moderate temperature in the range of 50 °C to 350 °C. The apparent activation energy for the decomposition of this new consolidated nanocomposite material was measured to be 92.2 kJ mol(−1), which is far below than the measured value of pure nanocrystalline MgH(2) powders (151.2 kJ mol(−1)) prepared in the present study. This new binary system possessed superior hydrogenation kinetics, indicated by the rather low temperature (200 °C) required to uptake 6.08 wt% H(2) within 7.5 min. More importantly, the system revealed excellent dehydrogenation kinetics at 225 °C as implied by the limited time needed to release 6.1 wt% H(2) in 10 min. The MgH(2)/5 wt% MG-Zr(2)Pd system showed a high performance for cyclability, implied by the achievement of continuous cycles (338 cycles) at 225 °C without degradation over 227 h.
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spelling pubmed-90708062022-05-06 Environmentally friendly nanocrystalline magnesium hydride decorated with metallic glassy-zirconium palladium nanopowders for fuel cell applications El-Eskandarany, M. Sherif Banyan, Mohammad Al-Ajmi, Fahad RSC Adv Chemistry A new solid-state hydrogen storage system of magnesium hydride (MgH(2)) doped with 5 wt% of metallic glassy (MG) zirconium palladium (Zr(2)Pd) nanopowder was fabricated using a high-energy ball milling technique. The end-product obtained after 50 h of milling was consolidated into bulk buttons, using a hot-pressing technique at 350 °C. The results have shown that this consolidation step, followed by the repetitive pressing at ambient temperature did not affect the nanocrystalline characteristics of pressed powders. Recycling pressing demonstrated beneficial effects of plastic deformation and lattice imperfections on Mg, leading to its enhanced hydrogenation/dehydrogenation kinetics and cycle-life-time performance compared with untreated samples. The results elucidated that spherical, hard, nanopowder of MG-Zr(2)Pd were forced to penetrate the Mg/MgH(2) matrix to create micro/nanopore structures upon pressing for 50 cycles. These ultrafine spherical metallic glassy particles (∼400 nm in diameter) acted as a micro-milling media for reducing the particle size of MgH(2) powders into submicron particles. In addition, they played a vital role as grain growth inhibitors to prevent the undesired growth of Mg grains upon the application of a moderate temperature in the range of 50 °C to 350 °C. The apparent activation energy for the decomposition of this new consolidated nanocomposite material was measured to be 92.2 kJ mol(−1), which is far below than the measured value of pure nanocrystalline MgH(2) powders (151.2 kJ mol(−1)) prepared in the present study. This new binary system possessed superior hydrogenation kinetics, indicated by the rather low temperature (200 °C) required to uptake 6.08 wt% H(2) within 7.5 min. More importantly, the system revealed excellent dehydrogenation kinetics at 225 °C as implied by the limited time needed to release 6.1 wt% H(2) in 10 min. The MgH(2)/5 wt% MG-Zr(2)Pd system showed a high performance for cyclability, implied by the achievement of continuous cycles (338 cycles) at 225 °C without degradation over 227 h. The Royal Society of Chemistry 2019-09-06 /pmc/articles/PMC9070806/ /pubmed/35530499 http://dx.doi.org/10.1039/c9ra05121j Text en This journal is © The Royal Society of Chemistry https://creativecommons.org/licenses/by-nc/3.0/
spellingShingle Chemistry
El-Eskandarany, M. Sherif
Banyan, Mohammad
Al-Ajmi, Fahad
Environmentally friendly nanocrystalline magnesium hydride decorated with metallic glassy-zirconium palladium nanopowders for fuel cell applications
title Environmentally friendly nanocrystalline magnesium hydride decorated with metallic glassy-zirconium palladium nanopowders for fuel cell applications
title_full Environmentally friendly nanocrystalline magnesium hydride decorated with metallic glassy-zirconium palladium nanopowders for fuel cell applications
title_fullStr Environmentally friendly nanocrystalline magnesium hydride decorated with metallic glassy-zirconium palladium nanopowders for fuel cell applications
title_full_unstemmed Environmentally friendly nanocrystalline magnesium hydride decorated with metallic glassy-zirconium palladium nanopowders for fuel cell applications
title_short Environmentally friendly nanocrystalline magnesium hydride decorated with metallic glassy-zirconium palladium nanopowders for fuel cell applications
title_sort environmentally friendly nanocrystalline magnesium hydride decorated with metallic glassy-zirconium palladium nanopowders for fuel cell applications
topic Chemistry
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9070806/
https://www.ncbi.nlm.nih.gov/pubmed/35530499
http://dx.doi.org/10.1039/c9ra05121j
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