Study of Energetics of Polaron Dynamics in Monolayer and Bulk MoS2Using Oxidation-State Constrained Density Functional Theory

We use oxidation-state constrained density functional theory (OS-CDFT) to study the polaron dynamics in the monolayer and bulk MoS2as well as in MoS2with the S and Mo vacancies. OS-CDFT is used to calculate the reorganization energies and driving forces of the polaron dynamics in MoS2. From our study, we find similar polaron hopping energetics for both monolayer and bulk MoS2. However, polaron hopping near an S vacancy has a high driving force such that it is in the Marcus inverted regime for both monolayer and bulk MoS2. This can explain the low electron mobility of monolayer MoS2found in experiments. Similarly, polaron hopping near an Mo vacancy is in the Marcus inverted regime for both monolayer and bulk MoS2. However, the driving force near an Mo vacancy is not as large as the driving force near an S vacancy.