Carrier mobility of one-dimensional vanadium selenide (V2Se9) monolayer and nanoribbon systems: DFT study

Abstract Vanadium selenide (V 2 Se 9 ) is a true one-dimensional (1D) crystal composed of atomic nanochains bonded by van der Waals (vdW) interactions. Recent experiments revealed the mechanical exfoliation of newly synthesized V 2 Se 9 . In this study, we predicted the electronic and transport properties of V 2 Se 9 through computational analyses. We calculated the intrinsic carrier mobility of V 2 Se 9 monolayers (MLs) and nanoribbons (NRs) using density functional theory and deformation potential theory. We found that the electron mobility of the two-dimensional (2D) (010)-plane ML of V 2 Se 9 is highly anisotropic, reaching μ 2 D , z e = 1327 cm 2 V −1 s −1 across the chain direction. The electron mobility of 1D NR systems in a (010)-plane ML of V 2 Se 9 along the chain direction continuously increased as the thickness increased from 1-chain to 4-chain NR (width below 3 nm). Interestingly, the electron mobility of 1D 4-chain NR along the chain direction ( μ 1 D , x e = 775 cm 2 V −1 s −1 ) was higher than that of a 2D (010)-plane ML ( μ 2 D , x e = 567 cm 2 V −1 s −1 ). These results demonstrate the potential of vdW-1D crystal V 2 Se 9 as a new nanomaterial for ultranarrow (sub-3 nm width) optoelectronic devices with high electron mobility.