Aluminene as Highly Hole Doped Graphene

TL;DR

This paper predicts the stability of a new monolayer aluminium structure called aluminene, which is a highly hole-doped graphene-like metal, based on density functional theory calculations.

Contribution

It introduces aluminene, a stable planar honeycomb aluminium monolayer, and analyzes its electronic properties using tight-binding and Dirac models.

Findings

Aluminene is the only stable aluminium monolayer structure among four configurations.

It exhibits a highly hole-doped graphene-like electronic structure.

Aluminene is predicted to be a metallic material.

Abstract

Monolayer structures made up of purely one kind of atoms are fascinating. Many kinds of honeycomb systems including carbon, silicon, germanium, tin, phosphorus and arsenic have been shown to be stable. However, so far the structures are restricted to group IV and V elements. In this letter, we systematically investigate the stability of monolayer structures made up of aluminium, in four different geometric configurations (planar, buckled, puckered and triangular), by employing density functional theory based electronic structure calculation. Our results on cohesive energy and phonon dispersion predict that only planar honeycomb structure made up of aluminium is stable. We call it "aluminene" according to the standard naming convention. It is a metal. Results of electronic band structure suggest that it may be regarded as a highly hole doped graphene. We also present the tight-binding model and the Dirac theory to discuss the electronic properties of aluminene.