Tunable Direct Semiconductor Gap and High Carrier Mobility of Mo <sub/>6</sub> Br <sub/>6</sub> S <sub/>3</sub> Monolayer

摘要： Two-dimensional materials with direct semiconductor gaps and high mobilities can play an important role in future electronic and optical applications. Here we propose that Mo6Br6S3 monolayer as a new two-dimensional material is stable and can be exfoliated from corresponding layered bulk. Our first-principles results show that the monolayer has a direct semiconductor gap beyond 1 eV (between PBE and HSE values) and a very high electron mobility (6880 cm2V?1s?1), and these can be tuned through in-plane strain by applying uniaxial stress. Furthermore, we show that the Mo6Br6S3/graphene heterostructure makes a p-type Schottky barrier and the amplitude of band bending (0.03 eV) is extremely low compared to other similar junctions because the Mo6Br6S3 monolayer has a close work function to graphene. With all these useful properties and functions, the Mo6Br6S3 monolayer can be very promising for nanoelectronic and optical applications.