Effects of hydrogen, oxygen, and hydroxyl adsorption on the electronic properties of transition metal dichalcogenides

The unique properties of 2D transition metal dichalgogenides (TMDs) attract a lot of interest for optoelectronics, catalysis and energy related applications. Strain, environment, nanostructuring, affect TMD electronic properties and intensive efforts focus on their controlled modification. We present DFT calculations for the stability and electronic structure of semiconducting MX₂ (M=Mo, W and X=S, Se) monolayers and nanostructures with several concentrations of adsorbed hydrogen, oxygen, and hydroxyl and compare our results with pristine systems. The metallic character of the edge states [1] is preserved for all TMD nanoribbons examined, albeit Fermi level shifts that depend on the adsorbed atoms. Tuning electronic properties with strain [2] for improved TMD catalysts [3] is briefly discussed.

1. D. Davelou et al, “Nanoribbon edges of transition-metal dichalcogenides: Stability and electronic properties”, Phys. Rev. B, 96, 165436 (2017).
2. A.E. Maniadaki et al, “Strain engineering of electronic properties of transition metal dichalcogenide monolayers”, Solid State Commun. 227, 33 (2016).
3. A.E. Maniadaki, G. Kopidakis, “Hydrogen on hybrid MoS₂/graphene nanostructures”, Phys. Status Solidi RRL 10, 453 (2016).