A theoretical analysis of the chemical bonding and electronic structure of graphene interacting with Group IA and Group VIIA elements

TL;DR

This paper provides a theoretical analysis of how graphene derivatives, called graphXene, interacting with Group IA and VIIA elements, can exhibit tunable electronic properties including variable band gaps, depending on atomic composition and structure.

Contribution

It introduces the concept of graphXene and demonstrates through theoretical analysis that their electronic properties, especially band gaps, can be precisely tuned by atomic composition.

Findings

Large band gaps can be achieved in some graphXene derivatives.

Semimetallic behavior is observed in other configurations.

Band gaps can be tuned between 0 and 6.4 eV by adjusting atomic concentration.

Abstract

We propose a new class of materials, which can be viewed as graphene derivatives involving Group IA or Group VIIA elements, forming what we refer to as graphXene. We show that in several cases large band gaps can be found to open up, whereas in other cases a semimetallic behavior is found. Formation energies indicate that under ambient conditions, sp$^3$ and mixed sp$^2$/sp$^3$ systems will form. The results presented allow us to propose that by careful tuning of the relative concentration of the adsorbed atoms, it should be possible to tune the band gap of graphXene to take any value between 0 and 6.4 eV.