Fig. 5: Theoretical studies of the Co-doping, Se-doping, and Co/Se-codoping effect in tuning the HER performance of MoS2.
From: Boosting hydrogen evolution on MoS2 via co-confining selenium in surface and cobalt in inner layer
a The adsorption free energies of H* (ΔGH*) at the in-plane, Mo-edge, and S-edge sites of pure, Co-doped, Se-doped, and Co/Se-codoped MoS2, denoted as MoS2, Co-MoS2, Se-MoS2, Co/Se-MoS2, respectively. The hydrogen coverage at the Mo-edge is defined according to the terminating S or Se monomer sites, while that at the S-edge is defined according to the terminating S or Se dimer sites which are the active sites for the HER. b Adsorption structures of H* at the in-plane, Mo-edge and S-edge sites of Co/Se-MoS2. c Relative formation energies of the Co/Se-codoped structures with different doping configurations of Co and Se being separated (Co/Se-separated, grid bars) or adjacent (Co/Se-adjacent, solid bars) to each other. d Structures of Co/Se-codoped basal plane, Mo-edge, and S-edge with Co/Se-separated and Co/Se-adjacent configurations (Supplementary Fig. 26).
