Effects of noble metal doping on hydrogen sensing performances of monolayer MoS₂

To develop a new kind of hydrogen sensor based on monolayer MoS₂, we investigated effects of noble metal doping on hydrogen sensing performances of the monolayer MoS₂ by using the first principles calculation method. The Cu, Pd, and Pt doping decrease the adsorption energy of a hydrogen molecule on the monolayer MoS₂, while Ag and Au doping have little effect on the adsorption energy. The adsorption energy change indicates that the Cu, Pd, and Pt doping strengthen the interaction between the hydrogen molecule and the monolayer MoS₂. The density of states shows that the hybridization of H s, noble metals d, S p, and Mo d orbitals contributes to the adsorption of the hydrogen molecule on the noble metal doped monolayer MoS₂. The changes in bader charge and charge density difference indicate that noble metal doping increases the charge transfer between the hydrogen molecule and the monolayer MoS₂. All of the results demonstrate that noble metal doping can improve the hydrogen sensing performances of the monolayer MoS₂, especially the Pd and Pt doping.