Searching for High-Performance Two-Dimensional Channel Materials from First-Principles Calculations

All of the two-dimensional (2D) semiconductors that have been fabricated show lower electrical transport than bulk silicon, which limits their practical application. It is thus desirable to discover new 2D semiconductors with high electrical transport. Here, using first-principles calculations, we sift out 159 2D semiconductors from the Materials Cloud two-dimensional crystals database (MC2D). It is found that 33 semiconductors show a higher dielectric constant than monolayer MoS2. The 2D Fröhlich bare potential is then calculated using the density functional perturbation theory. Combined with the dielectric properties, we estimate the polar optical phonon–electron scattering rates. Three 2D semiconductors, WCu2Se4, penta-PdS2, and InP3, are identified with weaker polar optical phonon–electron scattering than that of monolayer MoS2, indicating their potential application as 2D channel materials. We further carry out the Boltzmann transport equation with first-principles calculations to calculate the intrinsic electron mobility μe of monolayer InP3, which is 323 cm2 V–1 s–1, confirming its excellent electrical transport property.