Stabilizing γ-MgH2 at nanotwins in mechanically constrained nanoparticles

• Verfasst von: Kammerer, Jochen [VerfasserIn]
• Verfasst von: Duan, Xiaoyang [VerfasserIn]
• Verfasst von: Neubrech, Frank [VerfasserIn]
• Verfasst von: Schröder, Rasmus R. [VerfasserIn]
• Verfasst von: Liu, Na [VerfasserIn]
• Verfasst von: Pfannmöller, Martin [VerfasserIn]
• Titel: Stabilizing γ-MgH2 at nanotwins in mechanically constrained nanoparticles
• Verf.angabe: Jochen A. Kammerer, Xiaoyang Duan, Frank Neubrech, Rasmus R. Schröder, Na Liu, and Martin Pfannmöller
• E-Jahr: 2021
• Jahr: February 8, 2021
• Umfang: 9 S.
• Fussnoten: Im Titel ist 2 bei "γ-MgH" tiefgestellt ; Gesehen am 14.09.2021
• Titel Quelle: Enthalten in: Advanced materials
• Ort Quelle: Weinheim : Wiley-VCH, 1989
• Jahr Quelle: 2021
• Band/Heft Quelle: 33(2021), 11, Artikel-ID 2008259, Seite 1-9
• ISSN Quelle: 1521-4095
• DOI: doi:10.1002/adma.202008259
• Datenträger: Online-Ressource
• Sprache: eng
• Sach-SW: electron beam lithography
• Sach-SW: hydrogen storage
• Sach-SW: metastable
• Sach-SW: MgH2
• Sach-SW: nanomaterials
• Sach-SW: plasmonics
• Sach-SW: transmission electron microscopy (TEM)
• K10plus-PPN: 1770108351
• K10plus-PPN:
  Universitätsbibliothek
• Lokale URL UB: Zum Volltext

Abstract

Reversible hydrogen uptake and the metal/dielectric transition make the Mg/MgH2 system a prime candidate for solid-state hydrogen storage and dynamic plasmonics. However, high dehydrogenation temperatures and slow dehydrogenation hamper broad applicability. One promising strategy to improve dehydrogenation is the formation of metastable γ-MgH2. A nanoparticle (NP) design, where γ-MgH2 forms intrinsically during hydrogenation is presented and a formation mechanism based on transmission electron microscopy results is proposed. Volume expansion during hydrogenation causes compressive stress within the confined, anisotropic NPs, leading to plastic deformation of β-MgH2 via (301)β twinning. It is proposed that these twins nucleate γ-MgH2 nanolamellas, which are stabilized by residual compressive stress. Understanding this mechanism is a crucial step toward cycle-stable, Mg-based dynamic plasmonic and hydrogen-storage materials with improved dehydrogenation. It is envisioned that a more general design of confined NPs utilizes the inherent volume expansion to reform γ-MgH2 during each rehydrogenation.