The electronic structures, elastic constants, dielectric permittivity, phonon spectra, thermal properties and optical response of monolayer zirconium dioxide: A first-principles study

Zirconium dioxide (ZrO2) with great mechanical and dielectric properties can be widely used in both structural and functional material fields. In this paper, the first-principles calculations are performed to investigate the geometrical and electronic structures, elastic constants and mechanical stability, Born effective charges and dielectric permittivity, phonon spectra and thermal properties, as well as optical response of monolayer ZrO2. A wide indirect bandgap of 4.41 eV and a p-d hybridized ionic bond are presented in monolayer ZrO2, instead of a zero bandgap and a sp(2) hybridized covalent bond in grapheme. Both the large in-plane stiffness of 209.59 N/m and small Poisson's ratio of 0.24 imply monolayer ZrO2 a high strength in-plane and good flexibility out-plane. A strong dynamic charge transfer from Zr to O is existed in monolayer ZrO2. The large bandgap and dielectric permittivity, mechanical and dynamical stability show monolayer ZrO2 a promising two dimensional dielectric material. The high and sharp absorption peaks in the ultra-violet spectral region suggest monolayer ZrO2 a potential application as a ultra-violet detector.