A DFT study on the hydrogen storage performance of MoS2 monolayers doped with group 8B transition metals

The adsorption of hydrogen (H2) molecules on MoS2 monolayers doped with Fe, Co, Ni, Ru, Rh, Pd, Os, Ir or Pt was calculated via first-principle density functional theory (DFT). The H2 was found to interact most strongly with the MoS2 doped with Os with a higher adsorption energy of −1.103 eV. Investigations of the adsorptions of two to five H2 molecules on Os-doped MoS2 monolayers indicate that there are at most four H2 interacting stably with the substrate with a promising average adsorption energy of −0.792 eV. Molecular dynamics simulations also confirmed that the four H2 molecules can still be reasonably adsorbed and stored on the Os-doped MoS2 monolayer with a comparable average adsorption energy of −0.713 eV at 300 K. This study indicates that MoS2 monolayer doped with Os is a promising substrate to interact strongly with H2 and can be applied to effectively store H2 at room temperature.