Tuning the thickness of graphitic nanofilms for wurtzite materials by vertical weak electric field under a certain pressure

Abstract

Theoretical and experimental results indicate that naturally the ultrathin nanofilms of some wurtzite (WZ) semiconductors will transform into a stable nonpolar graphitelike structure from the polar surface. Normally, the thicknesses are just limited to a few atomic layers. By epitaxial tensile strain, the thickness can be extended. In this work, employing the first-principles calculations focus on WZ materials ZnO, BeO, SiC, GaN, InN and AlN, we predicted that under a certain pressure with a weak electric field, their thickness range of forming graphitic nanofilms is greatly enlarged. This research provides theoretical guidance for the synthesis of new two-dimensional (2D) structures.