  Recently, the two dimensional (2D) materials have become a potential
candidates for various technological applications in spintronics and
optoelectronics. In the present study, the structural, electronic, and phase
stability of 2D layered ZnSb compounds of four different phases viz.
wurzite(w), tetragonal (t), hexagonal (h), and orthorhombic (o) have been tuned
using the first principle calculations based on density functional theory
(DFT). We invoked the Perdew-Burke-Ernzerhof (PBE) functional and the projected
augmented wave (PAW) method during all the calculations. Based on our numerical
results, we predicted the novel tetragonal phase as stable phase of ZnSb next
to existing orthorhombic structure. We reported the pressure induced phase
transition between orthorhombic to tetragonal phase at 12.48 GPa/atom. The
projected density of states indicates the strong p-d hybridization between
Sb-5p and Zn-3d states confirming the nature of strong covalent bonding between
them. The electronic band structures suggest that t-ZnSb, w-ZnSb, and h-ZnSb
are metallic in nature whereas o-ZnSb is semiconducting with narrow band gap of
0.03 eV using PBE. We predicted the possibility of extracting the two
dimensional (2D) monolayer sheet in t-ZnSb and o-ZnSb according to the
exfoliation energy criterion. In addition, the 2D monolayer (ML) of o-ZnSb has
been predicted to be dynamically stable but that of t-ZnSb is not stable as
manifested in phonon dispersion bands. Surprisingly, the semiconducting band
gap nature of o-ZnSb changes from indirect and narrow to direct and sizable
while going from 3D bulk to 2D ML structure. Further, we estimated the value of
work functions for the surfaces of t-ZnSb and o-ZnSb as 4.61 eV and 4.04 eV
respectively. Such materials can find the niche applications in next generation
electronic devices utilizing 2D hetero-structures.
