The Unusual Mechanism Behind Enhanced Photocatalytic Activity and Surface Passivation of SiC(0001) via< Forming Heterostructure With MoS2 Monolayer

Two-dimensional (2D)/three-dimensional (3D) hybrid heterostructure has recently emerged as an effective method for improving photocatalytic efficiency. In this work, we perform a comprehensive first-principles study of the structural, electronic and optical properties of a novel 3D-SiC/2D-MoS2 heterostructure. The calculation results reveal that the SiC(0001) surface/MoS2 monolayer integrated heterostructure is Schottky contact with new chemical bonding contributed to the surface adhesion and optoelectronic properties. Meanwhile, the valence and conduction band edge positions of SiC and MoS2 changed with the Fermi level and formed a desired type-II band alignment, which greatly facilitate rapid separation of photogenerated carriers. Moreover, the surface state of SiC(0001) can be removed when combine with MoS2 and the bandgap of them are also reduced. Furthermore, Bader charge and charge density difference indicated that there is remarkable separated distribution of electrons and holes at the interface. T...