In-Situ TEM Observation for Dehydrogenation Mechanism in MgH2 with Catalyst

Eri Morita; Akifumi Ono; Shigehito Isobe; Yong Ming Wang; Naoyuki Hashimoto; Somei Ohnuki

doi:10.4028/www.scientific.net/MSF.654-656.2867

Paper Titles

Characterisation of Hydrogen Release Behaviour in Cast Mg-Ni Alloys by Synchrotron XRD and XAFS
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Hydrogen Exchange Effect in MgH₂-LiBH₄ System
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Observation of Hydrogen Distribution in a Eutectic Mg-Ni Alloy by the Silver Decoration Method
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Catalysing Effect of Intermetallic Compounds on Hydrogen Desorption Kinetics in Cast Magnesium Alloys
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In-Situ TEM Observation for Dehydrogenation Mechanism in MgH₂ with Catalyst
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High Water Diffusivity in Low Hydration Plasma-Polymerised Proton Exchange Membranes
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Development of High Power Density Solid Oxide Fuel Cells (SOFCs) for Long-Term Operation
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Effect of Flow Fields and Scan Rates on Performance of Micro-DMFC
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Rare Earth Element Aliovalent Doping Substitution and Electrochemical Performance of LiFe_1-x Nd_xPO₄
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HomeMaterials Science ForumMaterials Science Forum Vols. 654-656In-Situ TEM Observation for Dehydrogenation...

In-Situ TEM Observation for Dehydrogenation Mechanism in MgH₂ with Catalyst

Abstract:

We carried out in-situ observation on the catalytic effect of Nb2O5 in MgH2 by using a high voltage transmission electron microscope (HVEM). We synthesized two kinds of samples, which were prepared by ball milling and by hand mixing. In milled sample, Nb2O5 was not confirmed from high resolution images, however, NbO was identified. As the temperature increased, the decomposition of MgH2 proceeded, while Mg formed and grew. It suggested that NbO had the catalytic effect to promote the dehydrogenation of MgH2. In mixed sample, which was prepared to clearly observe the boundary between the catalyst and Mg phase, it was revealed that the dehydrogenation started from the boundary of MgH2 and Nb2O5. This result suggested that the dehydrogenation could proceed with hydrogen diffusion from MgH2 through Mg phase to the boundary.