High-Throughput Computational Screening of Two-Dimensional Semiconductors

By performing high-throughput first-principles calculations combined with a semiempirical van der Waals dispersion correction, we have screened 74 direct- and 185 indirect-gap two dimensional (2D) nonmagnetic semiconductors from near 1000 monolayers according to the criteria for energetic, thermodynamic, mechanical, dynamic and thermal stabilities, and conductivity type. We present the calculated lattice constants, simulated scanning tunnel microscopy, formation energy, Young's modulus, Poisson's ratio, shear modulus, anisotropic effective mass, band structure, band gap, ionization energy, and electron affinity for each candidate meeting our criteria. The resulting 2D semiconductor database (2DSdb) can be accessed via the website https://materialsdb.cn/2dsdb/index.html. The 2DSdb provides an ideal platform for computational modeling and design of new 2D semiconductors and heterostructures in photocatalysis, nanoscale devices, and other applications. Further, a linear fitting model was proposed to evaluate band gap, ionization energy and electron affinity of semiconductor from the density functional theory (DFT) calculated data as initial input. This model can be as precise as hybrid DFT but with much lower computational cost.