Hydrogen storage in TiFe nanoparticles: void-limited saturation and metal-selective charge transfer during sequential loading


KURBAN M., Serpedin E., Kurban H.

International Journal of Hydrogen Energy, cilt.250, 2026 (SCI-Expanded, Scopus) identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 250
  • Basım Tarihi: 2026
  • Doi Numarası: 10.1016/j.ijhydene.2026.156120
  • Dergi Adı: International Journal of Hydrogen Energy
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Artic & Antarctic Regions, Chemical Abstracts Core, Chimica, Compendex, Environment Index, INSPEC, Academic Search Ultimate (EBSCO), Engineering Source (EBSCO)
  • Anahtar Kelimeler: Adsorption thermodynamics, Hydrogen storage, Metal-selective charge transfer, Sequential hydrogen loading, TiFe nanoparticles, Void-limited saturation
  • Ankara Üniversitesi Adresli: Evet

Özet

We present an atomistic study of hydrogen uptake in an ultrasmall TiFe nanoparticle, linking H2 adsorption and dissociation at the surface with sequential interstitial loading, void accessibility, and charge redistribution. Fe-rich surface motifs favor dissociative H2 activation, and representative dissociation-path calculations show that Fe-associated cleavage is kinetically more accessible than the corresponding Ti-associated pathway. Internal storage is controlled by a limited set of void-like environments rather than generic interstitial insertion. Sequential loading remains predominantly exothermic, although discrete high-loading excursions appear because of site competition and local relaxation. Geometric analysis shows a crowding-driven approach to saturation, evidenced by decreasing minimum H–H separations and a heterogeneous clearance distribution with favorable sites in a near-surface/subsurface shell. Mulliken populations reveal progressive charging of the hydrogen sublattice with an asymmetric Ti/Fe host response, while local PDOS analysis supports electronically non-equivalent Ti-associated and Fe-associated dissociated environments. These results provide mechanistic descriptors for hydrogen uptake in nanostructured TiFe-based environments.