Strain-Tuned Structural, Mechanical and Electronic Properties of Two-Dimensional Transition Metal Sulfides ZrS2: A First Principles Study1

Abstract Two-dimensional semiconductor material zirconium disulfide (ZrS 2 ) monolayer is a new promising material with good prospects for nanoscale applications. Recently, a new zirconium disulfide (ZrS 2 ) monolayer with a space group of 59_ Pmmn has been successfully predicted. Using first-principles calculations, this new monolayer ZrS 2 structure is obtained with stable indirect band gaps of 0.65 eV and 1.46 eV at the DFT-PBE (HSE06) functional levels, respectively. Strain engineering studies on ZrS 2 monolayer show effective band gap modulation. The bandgap shows a linear regularity from narrow to wide under applied stresses (strain ranged from − 6% to + 8%). Young's modulus of elasticity of ZrS 2 rectangular cells along the tensile directions ( x -axis and y -axis) is 83.63 (N/m) and 63.61 (N/m) with Poisson's ratios of 0.09 and 0.07, respectively. The results of carrier mobility show that the electron mobility along the y -axis can reach 1.32×10 3 cm 2 V − 1 s − 1 . Besides, the order of magnitude of the light absorption coefficient in the ultraviolet spectral region is calculated to reach 2.0×10 5 cm −1 for ZrS 2 monolayers. Moreover, by regulating the bandgap under stress, some bandgaps of the stretched energy band exceed the free energy of 1.23 eV and possess a suitable energy band edge position. The results indicates that the new two-dimensional Pmmn -ZrS 2 monolayer is a potential material for photovoltaic devices and photocatalytic water decomposition.