Tuning Electronic Properties and Band Alignments of Phosphorene Combined With MoSe₂ and WSe₂

Abstract

Stacks of two-dimensional crystals in van der Waals heterostructures pave the way to novel applications in electronics and optoelectronics. Based on first-principles calculations, we study heterobilayers constructed with phosphorene on MoSe2 and WSe2. Both combinations are stable upon contact, while van der Waals interaction leads to a long-range structural bending, affecting electronic properties from phosphorene. Including quasiparticle effects, strong orbital overlaps are observed in the heterobilayers, influencing band offsets and, hence, emphasizing the importance of quasiparticle calculations over standard density functional theory ones. Interface effects also change the heterostructure type, modify local band gaps, and favor indirect transitions. To tailor the electronic properties of the heterostructures, interface interactions and external perturbations are taken into account through vertical pressures and electric fields. Uniaxial pressure strongly affects local direct gaps, and small electric fields can sweep band lineups and even change the heterostructure type. The studied features demonstrate the potential of bilayer systems for field-effect transistors, optoelectronic devices, and sensitive sensors.