High-Throughput\nComputational Screening of Two-Dimensional\nSemiconductors

Abstract

Two-dimensional\n(2D) materials have attracted great attention mainly\ndue to their unique physical properties and ability to fulfill the\ndemands of future nanoscale devices. By performing high-throughput\nfirst-principles calculations combined with a semiempirical van der\nWaals dispersion correction, we have screened 73 direct- and 183 indirect-gap\n2D nonmagnetic semiconductors from nearly 1000 monolayers according\nto the criteria for thermodynamic, mechanical, dynamic, and thermal\nstabilities and conductivity type. We present the calculated lattice\nconstants, formation energy, Young’s modulus, Poisson’s\nratio, shear modulus, anisotropic effective mass, band structure,\nband gap, ionization energy, electron affinity, and simulated scanning\ntunnel microscopy for each candidate meeting our criteria. The resulting\n2D semiconductor database (2DSdb) can be accessed via the Web site https://materialsdb.cn/2dsdb/index.html. The 2DSdb provides an ideal platform for computational modeling\nand design of new 2D semiconductors and heterostructures in photocatalysis,\nnanoscale devices, and other applications. Further, a linear fitting\nmodel was proposed to evaluate band gap, ionization energy, and electron\naffinity of 2D semiconductors from the density functional theory (DFT)\ncalculated data as initial input. This model can be as precise as\nhybrid DFT but with much lower computational cost.