Adsorption and dissociation of H2O molecule on the doped monolayer MoS2 with B/Si

Adsorption and dissociation of H2O on monolayer MoS2 surface doped with B/Si explored by first principle calculations coupled with climb image nudged elastic band method. The impurity B/Si atoms are more likely to occupy sulfur atom lattice positions with lower formation energies, which results in the breaking of surface chemically inertness of the MoS2 (001) plane. Free H2O molecules can be adsorbed on doped surfaces with lower adsorption energies, and form chemical bonds between oxygen and impurity atoms. Adsorbed H2O can be separated into OH radical and hydrogen adatom with a lower dissociation energy barrier on these doped systems (including impurity B/Si single doped, B and Si co-doped). Furthermore, the adsorbed OH radical can be further dissociated into oxygen and hydrogen adatoms on the surface of B and Si co-doped MoS2. Our theoretical study suggests that substrate of monolayer MoS2 doped with impurity B, Si may be a potential alternative choice for hydrogen evolution reaction.