Study of vacancy, voids, atom adsorption and domain substitution in hexagonal gallium nitride monolayer

Abstract

Inducing novel physical properties in two-dimensional (2D) materials for different applications has drawn great attention. In this work, the effects of vacancy, voids, atom adsorption, and domain substitution on the gallium nitride (GaN) monolayer are investigated using first-principles calculations. Stable pristine monolayer is a semiconductor 2D material with an indirect band gap of 1.95 eV. Significant magnetism is induced by creating single Ga vacancy, void types VGN, VGN2, VNG2, and VNG3, as well as N atom adsorption, where the N atoms around defects produce mainly the magnetic properties. In these cases, feature-rich electronic properties including magnetic semiconductor and half-metallic natures are obtained, which are suitable for applications in the spintronic devices. In addition, the energy gap can be effectively modified by VGN3 void, and III–V and IV-IV domains. In contrast, the monolayer is metallized upon Ga atom adsorption. Results presented herein introduce the formation of novel multifunctional 2D materials based on GaN monolayer for spintronic and optoelectronic applications.