【Others Papers】Oxygen vacancy-driven hydrogen adsorption in β-Ga₂O₃: A combined DFT and AIMD Investigation for sensing applications

      Researchers from the  Birla Institute of Technology & Science Pilani have published a dissertation titled "Oxygen vacancy-driven hydrogen adsorption in β-Ga₂O₃: A combined DFT and AIMD Investigation for sensing applications" in International Journal of Hydrogen Energy.

Abstract

      Oxygen vacancies strongly influence gas adsorption and electronic behavior in wide-bandgap oxides, but the effect of specific vacancy environments on H₂ interaction with monoclinic β-Ga₂O₃ remains unclear. In this work, density functional theory (DFT) and ab initio molecular dynamics (AIMD) were used to investigate H₂ adsorption on oxygen-deficient β-Ga₂O₃ with two non-equivalent vacancy sites and two adsorption geometries per site. The results show a clear site-dependent response: one vacancy site exhibits stronger H₂ binding, stronger suppression of vacancy-related electronic states, and greater dynamical confinement, while the other shows weaker coupling and higher molecular mobility. The key novelty of this work lies in the site-resolved comparison, which shows that vacancy geometry, rather than vacancy presence alone, governs adsorption strength, defect-state modulation, and thermal behavior. These findings provide atomistic insight for defect engineering of β-Ga₂O₃-based materials for H₂ sensing.

DOI：

https://doi.org/10.1016/j.ijhydene.2026.156474