The Band Gap of Graphene Is Efficiently Tuned by Monovalent Ions

TL;DR

This study systematically investigates how monovalent and divalent ions affect graphene's electronic structure, demonstrating that ion interactions can effectively tune its band gap for potential electronic applications.

Contribution

It provides new insights into how monovalent and divalent ions influence graphene's electronic properties, enabling targeted band gap engineering.

Findings

Li+ and Na+ ions tune the conduction band of graphene

Mg2+ shares orbitals with graphene, resulting in higher binding energy

Ion interactions can be used to engineer graphene's electrical properties

Abstract

Following recently published study of Prezhdo and coworkers (JPC Letters, 2014, 5, 4129-4133), we report a systematic investigation of how monovalent and divalent ions influence valence electronic structure of graphene. Pure density functional theory is employed to compute electronic energy levels. We show that LUMO of an alkali ion (Li+, Na+) fits between HOMO and LUMO of graphene, in such a way tuning the bottom of the conduction band (i.e. band gap). In turn, Mg2+ shares its orbitals with graphene. The corresponding binding energy is ca. 4 times higher than in the case of alkali ions. The reported insights provide inspiration for engineering electrical properties of the graphene containing systems.