Ab-initio study of the stability and electronic properties of wurtzite and zinc-blende BeS nanowires

TL;DR

This study uses first-principles calculations to analyze the stability and electronic properties of BeS nanowires in zinc blende and wurtzite phases, revealing size, shape, and surface effects on their semiconducting behavior.

Contribution

It provides a detailed ab-initio analysis of BeS nanowires' stability and electronic properties, highlighting the influence of surface dangling bonds and nanowire geometry.

Findings

WZ nanowires are more stable than ZB nanowires below 133.3 Å diameter.

Both ZB and WZ nanowires are semiconductors with size-dependent band gaps.

Surface dangling bonds significantly affect the electronic properties of the nanowires.

Abstract

In this work we study the structural stability and electronic properties of the Beryllium sulphide nanowires (NWs) in both zinc blende (ZB) and wurtzite (WZ) phases with triangle and hexagonal cross section, using first principle calculations within plane-wave pseudopotential method. A phenomenological model is used to explain the role of dangling bonds in the stability of the NWs. In contrast to the bulk phase, ZB-NWs with diameter less than 133.3 (angstrom) are found to be less favorable over WZ-NWs, in which the surface dangling bonds (DBs) on the NW facets play an important role to stabilize the NWs. Furthermore, both ZB and WZ NWs are predicted to be semiconductor and the values of the band gaps are dependent on the surface DBs as well as the size and shape of NWs. Finally, we performed atom projected density-of states (PDOSs) analysis by calculating the localized density of states on the surface atoms, as well as on the core and edge atoms.