Structural, Electronic, Mechanical, and Vibrational Properties of XE2H2 (X = Sr, Ba; E = Ga, Al) Zintl-Phase Hydrides: A First-Principles Assessment for Hydrogen Storage

Saadi T., Charifi Z., Ghellab T., Baaziz H., Ammi H., UĞUR Ş., ...Daha Fazla

Russian Journal of Physical Chemistry B, cilt.20, sa.9, ss.959-978, 2026 (SCI-Expanded, Scopus)

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 20 Sayı: 9
  • Basım Tarihi: 2026
  • Doi Numarası: 10.1134/s1990793126700624
  • Dergi Adı: Russian Journal of Physical Chemistry B
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Aerospace Database, Chemical Abstracts Core, Materials Science & Engineering Collection (ProQuest), Technology Collection (ProQuest)
  • Sayfa Sayıları: ss.959-978
  • Anahtar Kelimeler: hydrogen storage, mechanical stability, phonon dispersion, renewable energy, Thermal properties, Zintl hydrides
  • Gazi Üniversitesi Adresli: Evet

Özet

Abstract: This study investigates the structural, electronic, mechanical, and vibrational properties of Zintl-phase hydrides SrAl2H2, SrGa2H2, and BaGa2H2 using density functional theory with the Vienna Ab initio Simulation Package and projector augmented wave method. Band structure calculations (generalized gradient approximation and Heyd–Scuseria–Ernzerhof functional) reveal metallic behavior due to partially filled conduction bands and delocalized electrons near the Fermi level. Hydrogen storage capacities are calculated as 1.404 weight percent (SrAl2H2), 0.88 weight percent (SrGa2H2), and 0.723 weight percent (BaGa2H2). Elastic constants confirm mechanical stability with anisotropic behavior in the {100} plane. Phonon dispersion curves show no imaginary frequencies, confirming dynamic stability. The distinct separation of acoustic and optical modes arises from the large mass contrast between hydrogen and heavier atoms. Thermal analysis indicates that increasing temperature enhances entropy and promotes hydrogen desorption. These results highlight the potential of these hydrides as candidates for solid-state hydrogen storage, offering stable structures and promising desorption characteristics suitable for energy applications.