Density functional theory studies of interactions of graphene with its environment: substrate, gate dielectric and edge effects

TL;DR

This review summarizes density functional theory studies on how substrates, gate dielectrics, and edges influence graphene's electronic properties, including band gap opening and charge transfer effects.

Contribution

It provides a comprehensive overview of DFT insights into substrate and edge effects on graphene, highlighting specific interactions and their impact on electronic structure.

Findings

Silicon-terminated quartz does not perturb graphene's spectrum.

Oxygen-terminated quartz and alumina induce band gaps in graphene.

Edge properties and nanoribbon width affect the band gap size.

Abstract

This paper reviews the theoretical work undertaken using density functional theory (DFT) to explore graphene's interactions with its surroundings. We look at the impact of substrates, gate dielectrics and edge effects on the properties of graphene. In particular, we focus on graphene-on-quartz and graphene-on-alumina systems, exploring their energy spectrum and charge distribution. Silicon-terminated quartz is found to not perturb the linear graphene spectrum. On the other hand, oxygen-terminated quartz and both terminations of alumina bond with graphene, leading to the opening of a band gap. Significant charge transfer is seen between the graphene layer and the oxide in the latter cases. Additionally, we review the work of others regarding the effect of various substrates on the electronic properties of graphene. Confining graphene to form nanoribbons also results in the opening of a band gap. The value of the gap is dependent on the edge properties as well as width of the nanoribbon.