Bandgap engineering of zigzag graphene nanoribbons by manipulating edge states via defective boundaries

TL;DR

This paper proposes a method to induce a significant bandgap in zigzag graphene nanoribbons by manipulating edge defects, enabling their use in transistors without full separation from graphene.

Contribution

It introduces a general edge condition for bandgap opening in ZGNRs with defects, facilitating integration into graphene-based devices.

Findings

Defective edges can induce a significant bandgap in ZGNRs.

Embedded ZGNRs can function as transistors without full separation.

Proposed ZGNR FETs exhibit high performance.

Abstract

One of severe limits of graphene nanoribbons (GNRs) in future applications is that zigzag GNRs (ZGNRs) are gapless, so cannot be used in field effect transistors (FETs). In this paper, using tight-binding approach and first principles method, we derived and proved a general edge (boundary) condition for the opening of a significant bandgap in ZGNRs with defective edge structures. The proposed semiconducting GNRs have some interesting properties including the one that they can be embedded and integrated in a large piece of graphene without the need of completely cutting them out. We also demonstrated a new type of high-performance all-ZGNR FET.